SEPTEMBER 20, 1994 MINUTES
),I- N7i r-"-i I I if II
"WORLD'S LARGEST RESORT CITY"
(@l FY (@OLJN(@ll,
IIIIIN 11
CITY COUNCIL AGENDA
SEPTEMBER 20,1994
[rescheduled from September 6, 19941
1. CITY MANAGER'S BRIEFINGS - Council Chamber - 12:00 PM
A. WETLANDS BANKING SYSTEM
Ralph Smith, Director, Public Works
B. 25th STREET PARKING LOT
Sponsored by Mayor Meyera E. Oberndorf
Ii. INFORMAL SESSION - Council Chamber - 1:30 PM
A. CALL TO ORDER - Mayor Meyera E. Obemdarf
B. ROLL CALL OF CITY COUNCIL
C. RECESS TO EXECUTIVE SESSION
Ill. FORMAL SESSION - Council Chamber - 2:00 PM
A. CALL TO ORDER - Mayor Meyera E. Oberndorf
B. INVOCATION: Father James Parke
Church of the Ascension
C. PLEDGE OF ALLEGIANCE TO THE FLAG OF THE UNITED STATES OF AMERICA
D, ELECTRONIC ROLL CALL OF Cil.Y COUNCIL
E. CERTIFICATION OF EXECUTIVE SESSION
F. MINUTES
1 . INFORMAL & FORMAL SESSIONS September 13, 1994
G. RESOLUTION
Resolution to support the Citizens Flag Alliance of Virginia and the Commonweafth of
Virginia in their effort to secure a Constitutional Amendment giving the states the authority
to pass laws against the public intentional physical desecration of the United States Flag.
(Sponsored by Mayor Meyera E. Oberndort)
H. ORDINANCES
1. Ordinance to DECLARE a sixty-six (66)-foot-wide strip as EXCESS PROPERTY,
designated as Parcel C, running between Indian River Road and Princess Anne Road (a
former railroad right-of-way) in the petition of J. Harry and Katheryn H. Mots; and, to
AUTHORIZE the City Manager to dispose of same (PUNGO BOROUGH).
2. Ordinance to APPROPRIATE $165,557 from Storm Water Utility retained eamings to
Pembroke Area Regional Best Management Practices (BMP) Project #2-223 re funding
increased costs for construction of additional piped outfall capacity.
1. AUTHORIZATION
1 Authorize cash payment in lieu of open space dedications of less than one acre with the
Developer of Hidden Pointe Subdivision consistent with the policy for aoquisition and
development of park lands as outlined in the draft Virginia Beach Outdoors Plan.
Deferred: September 13, 1994
J. UNFINISHED BUSINESS
K. NEW BUSINESS
L. ADJOURNMENT
If you are physically disabled or visually impaired
and need assistance at this meeting,
please call the CITY CLERK'S OFFICE at 427-4303
Hearing impaired, call: TDD only 427-4305
(TDD - Telephonic Device for the Deaf)
PUBUC HEARING
CITY COUNCIL CHAMBER
SEPTEMBER 27,1994 - 6:00 PM
RE: ELECTORAL PLAN - Reapportionment
(Unfinished Business)
9/15/94/cmd
AGENDA\98-20-94.ITM
M I N U T E S
VIRGINIA BEACH CITY COUNCIL
Virginia Beach, Virginia
,Veptember 20, 1994
Vice Mayor W'll'a- D- SeSSO-s, Jr. called tO Order th, CITY MffAGERS
1'7RG'NL B C l' CITY COUNCIL . t BRIEFINGS to the
4 EA I h' CO-Ilcil Chamber, City Ha I Bilding, on Tuesda
Seplember 20, 1994, at 12:30 P.M. Y,
COuncil Members Present.-
John A. Baum, Robert Y- Dean, William w. Ha 0
Henley, Louis R.,Iones, John D, Moss, Nancy Krris n Jr., Barbara M.
William D. Sessonv, ir. I'arker and Vlce Mayor
Council Members Absent:
Mayor Meyera E, Ob(-rndorf [P,NTI',,REI): 12:18 P.M.]
Linwood 0. Iiran,-h, III [l-NTI,'PFI): 1.-06 l@M.]
Louisa M. @trayho,, IEN7TRID: ]:06 P.M.]
",ce MaY- Sesso-, beirig a Corporate officer of Central Fidelity Bank dilclosed there were no matters
the agenda in which he has a erso al interest,,
caPaci as an officer of Centra n , as defilled in the Act, either individually or i, his
ay -ty I Fide i Bank T e V- e r u , -kes this Disclosure as he
may not know of the Bank',v int I tY . h ic Mayor eg la ly
erest in any application that may come before City CounciL P',ce
Mayor Sessonu' letter of September 20, 1994, is hereby made a part of the record.
Councilman William W. Harrison, Jr., DISCLOSED pursuant t(,,@ecti(@n 2. I -639.14(E), Code of Virginia,
he is a partner ii' the law firm of Willcox & Savage, P. C., and eartis an ann,,al income that exceeds,
$10,000. Councilmati Harrisori provides repi-esentational servi(:e., and will excuse hinuelf from
participating in any meetings or di@v(,ussions of the Council wherel,, the interests of his clients may be
irivolved. Councilman Harrivoti',y letter ()f,@eptember 13, 1994, is her(lby made a part of the record.
WILLIAM D. SESSOMS, jR
VICE MAYOR
GREENTREE ARG@
VIRGINIA BEACH VIRGINFA 2.51
(80@) 413 39@6
September 20, 1994
Mrs. Ruth Hodges Smith, ('MC/AAE
City Clerk
Municipal Center
Virginia Beach, Virginia 23456
Re: Conflict of Interests Act
Dear Mrs. Smith:
In acCOrdance with tny letter to you dated August 10, 1993, 1 have thoroughly
reviewed the agenda for the September 20 1994, Meeting of City Council for the Purpose
i ct under the
of identifying -y matters in which I migh't have an actual or potent al conflait, to the best
Virginia Conflict of Interests Act. Based on that review, please be advised th
Of MY knowledge, there are no matters on the agenda in which I have a "personal interest,
as defined in the Act, either individually or in my capacity as an officer of Central Fidelity
Bank. Accordingly, I respectfully request that you record this letter in the official records
of the Council.
Thank you for your assistance and cooperafion in this matter.
Very truly yours,
I s, Jr.
Vice-Mayor
WDS,Jr./clb
- 2 -
CITY MANAGER'S BRIEFING
WETL4NDS BANKING SYSTEM
12:00 P.M.
ITEM # 38382
Harold Jones, Chief - Southern Virginia Regulator Section, US Army Corps of Engineers, advised as the
City continues to grow, wetlands impacts and the associated regulatory process will undoubtedly be
evoked As it is generally the philosophy of both the City, State and Federal Agencies to work to avoid
wedand impact when at all possible, there will undoubtedly be pr()jects where wedand @cts will have
to occur as a practical portion of that particular project. Rhen that occurs, al least historically to this
point, wetlands compensation has always been undertaken on an individual site specific basis. 77tis
becomes veryfragmented and the result is a multitude of individual projects scattered throughout the City
in various watersheds. The Wetlands Mitigation Banking System is the restoration, creation or
enhancement of wetlands or other aquatic habitats expressly for the purpose of providing compensatory
mitigation in advance of discharges itito wetlands permitted under the Section 404 regulatory program.
BENEFITS OF BANKING
Effective and adequate compensatory mitigation that is in -
place prior I() unavoidable project impacts.
Comprehensiv(, rather than fragmented compensatory mitigation.
Larger, easily managed, higher quality wetland sites rather
than numerous small sites.
Improved interagelicy coordination
Faster mitigatioii review - reduction in permit processing
time,v.
Ensure successful wetlands compen.Yatioti.
Reduced mitigatiori costs.
Richard Nettleton, Public Works -- (@ivil Fngineer, displayed the Flow Chart depicting Project Permit
Without Banking
WETL4ND BANKING
Compensatoty mitigation alternative to on-site mitigation.
Based on establivhing credits by restoration or creation of
wetland.
Dependent oii regulatory perniii review process for bank
debiting.
Operatioii of baiiks iv independent of regulatory permit review
process.
KEY DEFINITIONS
BANK - property having credits established by wetland restoration or
creation and expressly intended to provide compensatory mitigation for
wetland losses resulting from future construction activities undertaken by
the City.
BANK SITE - pr()perty designated for wetland restoration or creation
where credits are n(@t yet established
September 20, 1994
3
CITY MANAGER'S BRIEFING
WETL4NDS BANKING SYSTEM
ITEM # 38382 (Continued)
Mr. Nettleton displayed a chart depicting the process of BANKING.
CITY MRT 404 REG PROCESS
Propose Bank Site(s)
Propose Plans for Bank and
Development Criteria
" Plan
Propose Monitoring and ring and
Remediation Plans remediation plans
Constructldevelop
Monitor Bank Site Review Success of
Development, determine
Maintain Bank availability of credits (when
& how many)
Maintain Account Ledger Review Ledger
Review Permit with
KEY OPEK4TIONAL CONCEPTS
Bank operations are independent of the regulatory process.
Perntit review process determities proje(,t mitigation needs.
MRT determines bank success criteria, , redifing and debiting
plan (wetland design).
Bank developnient requires mortitoring reports and maintenance.
Perpetual conservation easement held by third party.
MEMORANDUM OF AGREEMENT (MOA)
Model (municipality banking system) for eastern United @tates
Framework j@)r establishing bankslbank sites within City.
Federal and State regulatory agencies and ('ity.
September 20, 1994
- 4 -
CITY MANAGER'S BRIEFING
25TH STREET PARKING LOT
1:05 P.M.
ITEM # 38383
Mayor Oberndorf introduced the 2-Minute film produced by VBTV re "person-on -the-street " interviews
with citizens and tourists about the new 25th Street Parking Lot. It is being shown to tell citizens that
based on their input, the City has heard their concerns about parking on the oceanfront and this is one
method of making improvements.
September 20, 1994
- 5 -
ITEMS OF THE MAYOR
1:08 P.M.
ITEM # 38384
Mayor Oberndorf advised Councibnan Dean will ADD to the Formal Session a Resolution authorizing
the City Manager to execute a Memorandum of Agreement for a Wetlands Banking System in the City
of rirginia Beach.
,5eptember 20, 1994
- 6 -
ITEM # 38385
Mayor Meyera E. Oberndorf called to order the INFORMAL SESSION of the U7RGINL4 BFACH CITY
COUNCIL in the Council Chamber, City Hall Building, on Tuesday, September 20, 1994, at ]:10 P.M.
Council Members Present.-
John A. Baum, Linw(x)d 0. Branci4 III, Robert K Dean, William W.
Harrison, Jr., Barbara M. Henley, Louis R. Jones, John D. MossMayor
Meyera E. Oberndorf, Nancy K Parkcr, Vice Mayor William D. @essoms,
Jr. and louisa M. @trayhorti
Council Members Absent:
None
September 20, 1994
- 7 -
ITEM # 38386
May- MeY- E. Oberndorf entertained a motion to permit City C,,ncil to conduct its EXECUTIVE
SESSION, pursuant to Sectio. 2,1 -344, Code of li,@ila, as amende,4 for the following purpose:
- Discu-io. - consideration f r i teje.
0,prospective candidat
1 es fOr emPlOYmelt, assignment, appointinent,
PrO'nOt'O@ PerfOrmance, demotion, salaries, disciplining, or resignation
of specific public officers, appointees, - e-ployees pursuant to Section
21-344 (A) (1).
ApPOintments: Boards@ and Commisions:
Community Development Cilizens AdvisorY Committee
'Flistorical Review Board
Transportation Safety Commission
"ML - Human Development Comnittee Commission
@MI, - P"blic safely commitice
Wetlands Board
UP- -tion by Vice Mayor Sessoms, secotided by Coun,-il Iady,@iryh,rn, City Council voted toproceed
into EXECUTIVE SEssioN.
Voting: 11-0
Council Members Voting Aye.-
John A. Baum, Linw(x)d 0. Branch, III, Robert K Dean, wzlliam W.
Harrison, Jr., Barbara M. Henley, Louis R Jones, John D. Moss, Mayor
Mey-a E- Oberndorf, Nancy K Parker, Vice Mayor William D. Sessow,
Jr. and Louisa M. ;trayhorn
Council Members Voting Nay:
None
Council Members Absent.@
Non e
September 20, 1994
9
e-
CERTIFICATION oF
EXECUTIVE SESSION
ITEM # 38387
Upon twtion by Vice MayorSessoms, econded by Council Lady Parker, City Council CERTIFIED THE
EXECUTIVE SESSION TO BE IN ACCORDANCE WITH THE MOTION TO RECESS.
Only public busitiess tnatters lawfidly exempted from Open Meeting
requirements by Virginia law were discussed in Fxecutive @ession to
which this certification resolution applies;
AND,
Only such public business matters as were identified in the motion
convening the Executive Session were heard, discuvsed or considered by
Virginia Beach (@ity CounciL
Voting: 11-0
Council Members Voting Aye,-
John A. Baum, Linwood 0. Branch, III, Robert K Dean, William W
Harrison, Jr., Barbara M. Henley, Louis R. Jones, John D. Moss, Mayor
Meyera E. Oberndorf, Nancy K Parker, Vice Mavor William D. .5essoms,
Jr. and Louisa M. 5trayhorn
Council Members Voting Nay:
None
Council Members Absent:
None
September 20, 1994
CERTIHCATION OF EXECUTIVE SESSION
VIRGINIA BEACH CITY COUNCIL
WHEREAS: The Virginia Beach City Council convened into EXECUT'IVE SESSION,
pursuant to the affirmative vote recorded in ITEM # 38386, Page No. 7, and in accordance with
the provisions of Tle Virginia Freedom of Information Act; and,
WHEREAS: Section 2.1-344. of the Code of Virginia requires a certiflcation by the
goveming body that such Exccutive Session was conducted in conformity with Virginia law.
NOW, THEREFORE, BE IT RESOLVED: That the Virginia Beach City Council
hereby certifies that, to the best of each member's knowledge, (a) only public business matters
lawfully exempted from Open Meeting requirements by Virginia law were discussed in Executive
Session to which this certification resolution applies; and, (b) only such public business mattcrs
as were identified in the motion convening this Executive Session were heard, discussed or
considered by Virginia Beach City Council.
Ruth Hodges Smith, CMC/AAE
City Clerk Septembcr 20, 1994
- 10 -
m I-F.
MINUTES ITEM # 38388
Upon motton by Vice Mayor Sessoms, seconded by Council Lady Strayhorn, City Council APPROVED
the Minutes of the INFORMAL AND FORAL4L SESSIONS ,f,5eptembe, 13, 1994, AS AMENDED
ITEM # 38368, Page 29
ORDINANCE UPON AIIPLICATION OF QUI(,K 10 CoRpoR,4TION
FOR A CONDT17ONAL USE PERMIT FOR,4N A UTOMOBILE,5ERVICE
STATION AND (,AR WASH R09941913
Condition No. 5,vhall COPRECTLY read:
5. A right deceleration turti lane with curb cut ()ff Baxter Road
into site.
Voting: 11-0
Council Members voting Aye:
John A. Baum, l,inw()od 0. Branch, III, Robert K Dean, William W
Harrison, Jr., Barbara M. Henley, Louiv R. Jones, John D. Moss, Mayor
Meyera E. Oberndorf Nancy K Parker, Vice Mavor William D. .5essoms,
Jr. and Louisa tl. Strayhorn
Council Members Voting Nay:
Non e
Council Members Absent:
None
,5eptember 20, 1994
te- III-G 1.
RESOLUTION ITEM 38389
A motion was made by Councilman Brancl; seconded by Vice Mayor Sessoms to ADOPT a Resolution
to support the Citizens Flag Alliance of Virginia and the Commonwealth of rzrginia in their effort to
secure a Constitutional Ainendment giving the states the authority to pass laws against the publfc
intentional physical desecratiott of the United States Flag.
Counciltnan Moss cited the opinion of Ihe Supreme Court, Justice Brennan when the Flag Act of 1989
was deemed to be unconstitutional. Ati impassiorted speech of @enator Kerry of Massachusetts, a much
decorated veteran of the Viet Nam War on the @nate I,'Ioor was alvo quoted. (,opies of same are hereby
made a Part of the record.
A motion was made by Councilman Dean to REFER TO THE UNITED STATES SUPIZEME COURT
the Resolution to support the Citizens Flag Alliance of rirginia and the Commonwealth of Virginia in
their effort to secure a Coristitutioiial Amendment giving the states the authority to pass laws against the
public intentional physical desecratioti ()f the United States Flag. SAID MOTION WAS WTHDR,4fM
A motion was made by Counciltnaii Dean, secotided by Council Lady Henley to TABLE the Resolution
to support the Citizens Flag Alliance of Virginia and the Commoiiwealth of Firginia in their effort to
secure a Constitutional Amendineiii giving the states the authority to pavv laws against the public
intentional physical desecratioii ()f the United States FLag.
Voting: 5-6 (MOTION LOST TO A NEGATIVE VOTE)
Council Members Voting Aye:
Robert K Deari, William W. Ilarrison, Jr., Barbara M. llenley, J()hn D.
Moss and Nanc@, K. Iarker
Council Members Voting Nay:
John A. Bawn, Liriwood 0. Branch, III, Louis R. Jones, Mayor Meyera
E. Oberndorf, Vice Mayor William D. Sessoms, Jr. and Louisa M.
Strayhorti
Council Mcmbers Absent:
Non e
September 20, 1994
- 12 -
I-G.1
RESOLUTION ITEM # 38390
UPOn -tion by Councilman Branch, seconded by Vice Mayor 5essoM, City Council ADOPTED:
Resolution to support the Citizens Flag Alliance of Virginia and the
Commonwealth of Virginia in their effort to secure a Constitutional
Amendment givitig the states the authority to pasv laws against the public
intentional physical desec-tion of the United States Flag. (,@ponso,ed
by Mayor Meyera E. Oberndorf)
Voting: 6-5
Council Members Voting Aye:
John A. Baum, f,inwood 0. Braricl4 III, Louis R. Jones, May()r Meyera
f,'. Oberndorf, Vic(, MaYor William 1). Sessom.1/2, Jr. and i,ouisa M.
,Strayhorn
Council Members Voting Nay.
Robert K Dean, William W IIarrison, Jr., Barbara M. Henley, John D.
Moss and Naiic-v K ilarker
C(@uncil Members Absent:
Non e
,@eptember 20, 1994
Requested by Mayor Meyera E. Oberndorf
RESOLUTION
2
3
4 WHEREAS, although the right of free expression is part of
5 the foundation of the United States Constitution, very carefully
6 drawn limits on expression in specific instances have long been
7 recognized as legitimate means of maintaining public safety and
8 decency, as well as orderliness and productive value of public
9 debate;
10 WHEREAS, certain actions, although arguably related to
11 one person's free expression, nevertheless raise issues concerning
12 public decency, public peace, and the rights of expression and
13 sacred values of others;
14 WHEREAS, there are symbols of our national soul such as
15 the Washington Monument, the United States Capitol Building, and
16 memorials to our greatest leaders, whict, are the property of every
17 American and are, therefore, worthy of protection from desecration
18 and dishonor;
19 WHEREAS, the American Flag to this day is a most
20 honorable and worthy banner of a nation which is thankful for its
21 strengths and committed to curing its faults, and remains the
22 destination of millions of immigrants attracted by the universal
23 power of the American ideal;
24 WHEREAS, the Constitution, as interpreted by the United
25 States Supreme Court, no longer accords to the Stars and Stripes
26 the reverence, respect, and dignity befitting t@le banner of that
27 most noble experiment of a nation-state;
28 WHEREAS, it is only fitting that people everywtiere should
29 lend their voices to a forceful call for restoratdon to the Stars
30 and Stripes of a proper station under law and decency;
31 WHEREAS, the General Assembly of the Commonwealth of
32 virginia, along with the legislatures of forty-three (43) other
33 states, have approved memorializing resolutions calling on Congress
34 to propose an amendment to the United States Con@3titution that
3 5 would give the states the authority to pass laws aqainst the public
36 intentional physical desecration of the United States Flag;
37 WHEREAS, the forty-four (44) states represent nearly
38 ninety-four percent (94%) of the United States poplilation;
39 WHEREAS, the American Legion, mc)re than forty (40) other
40 veterans and community organizations, and private ci.tizens have
41 formed the Citizens Flag Alliance, an apolitical, non-partisan
42 coalition whose express purpose is to influence Congress to propose
43 a Constitutional amendment to protect the Flag, and to encourage
44 the states to ratify said amendment; an(i
45 WHEREAS, the Citizens Flag Alliance has been incorporated
46 in the Commonwealth of Virginia with each state forniing its own
47 affiliate alliance.
48 NOW, THEREFORE, BE IT RESOLVED BY THE COUNCII. OF THE CITY
49 OF VIRGINIA BEACH, VIRGINIA:
50 That City Council hereby supports the Citizens Flag
51 Alliance of Virginia and the Commonwealth of Virginia in their
52 effort to secure a Constitutional amendment giving the states the
53 authority to pass laws against the public intentional physical
54 desecration of the United States E'lag.
55 AND BE IT FURTHER RESOLVED:
56 That the City Clerk is hereby directed to send copies of
57 this resolution to the Citizens Flag Alliance of Virginia, to each
58 member of the City's local delegation to the General Assembly of
59 the Commonwealth of Virginia, and to (@ach member off Virginia's
60 congressional delegation in Washington, D.C.
61 Adopted by the Council of the City of Virginia Beach,
62 Virginia, on the 20 day of September 1994.
63
64 CA-5724
65 R-2
66 Noncode/Flag.Res
67 September 15, 1994
2
- 13 -
ORDINANCES ITEM # 38391
J, HarrY Mote, 4307 Oceal I'@rod Avenue, phone: 499_8533, the applicant
UP- notion bY Council Lady He,ly, seconded by rice May- Sessolm,
th'r'y days -til the City Cou"c" '@essill" of October 25, 19'94.- CitY Council DEFER"D for
Ordinance to DEC@ a - tY 66 (x I
PROPERTY, desg,,aled s- -s- ( )-f It-w de strp ,s EXCESS
and Princess Anne Road (as Parcel C, -nninr between Indian Riler Road
a for er rai road righ
of J- HarY -d Katheryn Hm 1 1-Of-waY) in thepetition
Manager to dlYpov(, - Afote; and, to AUTHORIZE the Cty
of 'm' (PUN(,'O BOROU(,Ii).
Voting: 11-0
Council Afenbrs VOting Aye.
John A. Ba-, Linwood 0. Branh, III, Robert K Dea, Willia W
Ha-i 011, Jr., Barbara M. Henily, Louis R. ione,, John D. Moss, MaVor
s m
MeY- E Obe-dorf, Nancy K Parker, ce May- 11 a I).
Jr. and Louisa M. Ytrayho - P' Wi I m Velso;ns,
rti
COuncil Metnbers votllg Nay:
None
Council Member, Abse,,t:
No@ie
,@eptember 20, 1994
- 14 -
e- II- 2.
ORDINANCES ITEM # 38392
Upon motion by Councilman ionev, seconded by Councibnan M()ss, City Council ADOPTED:
Ordinance to APPROPRL4TE $165,557 from Storm Water Utility
retained eartiings to Pembroke Area Regional Best Management
Practic- (BMP) 1roject #2-223 re increased funding costs for
constructic)n of additional piped outfall capacity.
Voting: 11-0
Council Members Voting Ayc:
John A. Baum, Linwood 0. Branch, III, Robert K Dean, Wzlliam W
Harrison, Jr., flarbara M. Hetiley, Louis R. Jones, John D. Moss, Mayor
Meyera E@ Oberndorf, Nancy K Parker, Vice May(,r William D.,5essoms,
Jr. and Louiva M. @trayhorti
Council Members Voting Nay:
Noiie
Council Members Absent:
None
September 20, 1994
I AN ORDINANCE TO APPROPRIATE $165,557 FROM STORM
2 WATER UTILITY RETAINED EARNINGS TO PEMBROKE
3 AREA REGIONAL BMP PROJECT it2-223 IN ORDER TO
4 FUND THE INCREASED COSTS FOR CONSTRUCTION
5 OF ADDITIONAL PILPED OUTFALL CAPACITY
6 WHEREAS, the Pembroke Area Regional BMP Project #2-223 includes construction of a
7 wet detention pond, an intake storm water drainage pipe, and an outfall drainage pipe from the pond
8 to an existing outfau pipe to Thalia Creek,
9 WHERFAS, the existing outfall pipe to Thalia Creek has limited capacity, and requires
I 0 additional outfall pipe construction at an estimated cost of $165,557,
1 1 WHEREAS, private development construction activity and the dedication of a drainage
12 easement vathin the area coincides with the timing of the proposed piped outfall improvements,
1 3 WHEREAS, $165,557 is available for appropriation from Storm Water Utility Retained
14 Earnings.
1 5 NOW, THEREFORE, BE IT ORDAINED BY THE COUNCII, OF THE CITY OF
16 VIRGINIA BEACH, VIRGINIA, that funds in the amount of $165,557 be appropriated from
1 7 Storm Water Utility Retained Earnings to Pembroke Area Regional BMP Project #2-223 in order to
1 8 construct additional piped outfall capacity.
1 9 This ordinance shall be in effect from the date of its adoption.
20 September
20 Adopted the - day of 1994, by the Council of the City of Virginia Beach,
2 1 Virginia,
APPROVED AS TO CONTENT
Walter C. Krae@r, Jr
Department of Management and Budget
f./SWJ/PEMBRBMP.ORD
15 -
em
AUTHORIZ,4TION ITEM * 38393
Joe "arton, 440 Viking Drive, Phone: 498-1112, represented the applicant
Upon motion by Vice Mayor Sessomv, seconded by Council Lady @trayhorn, City Council AUTHORIZED:
Cash payment in lieu of open space dedications of less than one acre
with the Developer of Hidden Pointe Subdivision consistent with the
Policy for acquisition and development of park lands as outlined in the
draft Virginia Beach Outdoors Plan.
Voting: 11-0
Council Members Voting Aye:
John A. Baum, Linwood 0. Brancl; III, Robert K Dear; William W.
Harrison, Jr., Barbara M. Henley, Louis R. Jones, John D. Moss, Mayor
Meyera E. Oberndorf Nancy K Parker, Vice Mayor William D. Sessoms,
Jr. and Louiva M. Strayhorn
Council Members Voting Nay:
None
Council Meinbers Absent:
None
September 20, 1994
- 16 -
ii-J.
APPOINTMENTS ITEM # 38394
UPon NOMINATION by Vice Mayor Sessoms, City Council APPOINTED:
WETL,4NDS BOARD
Colonel John T Sprague, Jr.
Unexpired Term thru 09130197
Voting: 11-0
Council Members Voting Aye:
John A. Baum, Linwood 0. Branch, III, Robert K Dean, William W.
Harrison, Jr., Barbara M. Henley, Louis R. Jones, John D. Moss, Mayor
Meyera E. Oberndorf Nancy K Parker, Vice Mayor William D. Sessoms,
Jr. and Louisa M. @rayhorn
Council Members Voting Nay.
Non e
Council Members Absent.
None
,@eptember 20, 1994
- 17 -
tem III-J 2 a
NEW BUSINESS ITEM # 38395
Upon motion by Councilman Dean, seconded by Councilman Moss, City Council AGREED TO ADD To
THE AGENDA:
Resolution authorizing the City Manager to execute a Memorandum of
Agreement re a Wetlands Banking System between the Environmental
Protection Agency and the U.S. Army Corps of Engineers concerning the
Determinatiott of Mitigation under the Clean Water Act.
Voting: 11-0
Council Members Voting Aye:
John A. Baum, Linwood 0. Branch, III, Robert K Dean, William W
Harrison, Jr,, Barbara M. Henley, Louis R. Jones, John D. Moss, Mayor
Meyera E. Oberiidorf Nancy K Parker, Vice Mayor William D. ,;essoms,
Jr. and Louisa M. ';Irayhorn
Council Members Voting Nay.
None
Council Members Absent:
None
September 20, 1994
- 18
em I-J b.
NEW BUSINESS ITEM # 38395 (Continued)
Upon motion by Councibnan Dean, seconded by Councilman Mosv, City Council ADOPTED:
Resolution authorling the City Manager to execute a Memorandum of
Agreement re a Wetlands Banking System between the Environmental
Protectiort Agency atid the U.S. Army Corps of Engineers concerning the
Determinatioti (@f Mitigatiori under the Clean Water Act,
Voting: 11-0
Council Members Voting Aye:
John A. Baum, Linw()Od 0. Branch, III, Robert K Dean, William W
Harrison, Jr., Barbara M. Henley, Louis R. Jones, John D. Moss, Mayor
Meyera E. Oberndorf Nancy K Parker, rice Mayor William D. ,;essoms,
Jr. and Louisa M .5trayhorn
Council Members Voting Nay:
None
Council Members Absent:
Norie
September 20, 1994
4
1 A RESOLUTION AUTHORIZING THE CITY
2 MANAGER TO EXECUTE A MEMORANDUM OF
3 AGREEMENT FOR A WETLAND BANKING
4 SYSTEM IN THE CITY OF VIRGINIA
5 BEACH.
6 BE IT RESOLVED BY THE CITY COUNCIL OF THE CITY OF VIRGINIA
7 BF.ACH, VIRGINIA:
8 WHEREAS, from time to time, projects undertaken pursuant to
9 the City's Capital Improvement Program (CIP) cause unavoidable
10 impacts upon wetlands; and
11 WHEREAS, state and federal wetland permitting agencies may
12 require the City to provide compensatory mitigation for such
13 unavoidable impacts as a condition of the permit process; and
14 WHEREAS, wetland mitigation banking is a mechanism available
15 to the City to facilitate compensation for CIP generated wetland
16 mitigation requirements; and
17 WHEREAS, wetland mitigation banking systems are approved for
is use as a mitigation measure in accordance with the Council on
19 Environmental Quality Regulations 40 C.F.R. 1508.20; and
20 WHEREAS, City staff, in concert with the various state and
21 federal wetland permitting and regulatory agencies, have developed
22 a Memorandum of Agreement which will assure such agencies that
23 adequate compensatory mitigation will be in place prior to the
24 occurrence of wetland impacts arising from City CIP projects
25 through the acquisition or designation of property for wetland
26 mitigation banking; and
27 WHEREAS, the Virginia Open-Space Land Act, Section 10.1-1700
28 et sea. of the Code of Virginia, 1950, as amended, provides
9 localities the authority to acquire or designate property for the
0 purpose contemplated by the Memorandum of Agreement; and
1 WHEREAS, the Council of the City of Virginia Beach wishes to
2 proactively pursue any and all measures necessary to minimize or
3 mitigate impacts to wetlands.
34 NOW THEREFORE, BE IT RESOLVED BY THE COUNCIL OF THE CITY OF
35 VIRGINIA BEACH, VIRGINIA:
36 That the City Manager is hereby authorized to execute the
37 attached Memorandum of Agreement for a wetland banking system in
38 the City of Virginia Beach.
39 Adopted by the Council of the City of Virginia Beach,
40 virginia, on this 20 day of September 1994.
41 CA-5636
42 ordin\noncode\MOA.res
R-1
Prepared: 06/24/94
DEPARTME@ll
APPROVED AS TO I.EGAL
2
I
NMMORANDUM OF AGREEMIENT
FOR A WETLAND BANKING SYSTEM
IN THE CITY OF VIRGMU BEACH,
VIRG
24 June 1994
MEMORANDUM OF AGREEMENT
WETLAND BANKING SYSTEM
1. UMODucnON
A. Purpose and Scope: This document establishes procedures for developing a wetland
banking system to provide effective compensatory mitigation for unavoidable impacts to
wetlands resulting ftom construction activities undertaken by the City of Virginia Beach
(City) after execution of this MEMORANDUM OF AGREEMENT (MOA).
Fundamental to this MOA is the recognifion by the undersigned that use of the wedand
banidng system is an altemative when on-site mifigation is neither appropriate nor pracficable
or when a wetland mitigation bank will result in a higher functional wetlands than on-site
mitigation. The analysis steps of the Section 404(b)(1) Guidelines of the Clean Water Act
and the Corps public interest review will be followed for each proposed construction project
by the City where Secdon 404 permits are required.
'Me wetland banking system is intended for use in accordance with the Clean Water Act
Section 404(b)(1) Guidelines (40 CFR Part 230), the Memorandum of Agreement between
MEMORANDUM OF AGREEMENT 2
WETLAND BANKING SYSTEM
the Environmental Protecfion Agency and the Department of the Army Conceming the
Determination of Mitigafion under the Clean Water Act Secfion 404(b)(1) Guidelines
(February 6, 1990), the National Environmental Policy Act Implementing Regulations
(40 CFR 1508.20), and the Corps regulations (33 CFR Parts 230 through 330) when
determined through the regulatory permit review process:
1. that a less environmentally damaging practicable altemative to the
discharge of dredged or fill material in a wetland has not been identified;
2. all appropriate and practicable measures to minimize wetland impacts are
incorporated into the project;
3. on-site mitigation of wetland impacts is not appropriate nor practicable or
the use of the wetland mitigation bank yields a higher quality wetlands; and,
4. the proposed project is not contrary to the public interest.
Once the regulatory permit review process has determined the project meets the above
criteria, an established mitigafion bank may be used to compensate any unavoidable wetland
impacts stemming from the project of any City govemment department that is solely and
expressly undertaken for the benefit of the public. The banidng system is not intended for
use in any projects that solely benefit private development interests.
Operation of this mitigafion banldng system will be accomplished independent of afl agency
regulatory processes. Each regulatory agency will make independent permit decisions, as
required by their statutory authorities, regarding the applicability of individual projects to use
MEMORANDUM OF AGREEMENT 3
WETLAND BANKING SYSTEM
a mitigation bank to offset unavoidable wetland impacts. The process of the Mitigation
Review Team (MRI) is independent of the regulatory process. Only after the regulatory
agencies have completed their review of the project and have issued all appropriate permits
may the unavoidable wetland impacts be compensated for through use of a wetland mitigation
bank. Written approval shafl be in the form of permit conditions.
B. Goals: This MOA signifies a commitment to protect and preserve the remaining wetlands
in this city and to strive toward an immediate goal of no net loss with a long-term goal of a
net gain in improved wetland acreage and function. Ile goal of the wetland banldng system
under this MOA is to replace the functions and values of wetlands anticipated to be lost or
altered as a result of the City's neces&wy construction. All @tigation banks will be designed
to ensure maintenance and restoration of the physical, chemical, and biological integrity of
the aquatic ecosystem.
C. Background: The mitigafion banking system will be used as a compensatory mitigative
measure to offset unavoidable wetland impacts from the City's construction activities.
Proposed construction projects wifl be evaluated in accordance with the Council on
Environmental Quality Regulations (40 CFR 1508.20), the Memorandum of Agreement
between the Environmental Protection Agency and the Department of the Army Conceming
the Determination of Mitigafion Under the Clean Water Act Section 404(b)(1) Guidelines
(February 6, 1990), and Corps regulation (33 CFR Parts 320 through 330). The mitigation
banidng system provides assurance to the federal and state resource agencies that adequate
MEMORANDUM OF AGREEMENT 4
WETLAND BANKING SYSTEM
and appropriate compensation can and will be provided. Successful compensation, as
determined by the success criteria and approved by the MRT, wifl be in place prior to the
occurrence of impacts and properly credited to the bank prior to individual project
withdrawal.
D. Identification of W Functions and Banking Benefits: It is generally recognized
that the benefits of wetlands include, but are not limited to, the following:
1. groundwater recharge and discharge,
2. flood flow attenuation and alteradon,
3. sediment stabilization and shoreline anchoring,
4. water quality improvement,
5. food chain support,
6. wildlife habitat,
7. aquatic habitat,
8. uniqueness and heritage, and
9. recreation.
Benefits of a wetland banking system include, but are not liniited to:
1. Effective and adequate compensatory mitigation that is in-place prior to
unavoidable wetland impacts.
2. Comprehensive rather than fragmented compensatory mitigation.
MEMORANDUM OF AGREEMENT 5
WETLAND BANKING SYSTEM
3. @ger, easily managed, higher quality wetland sites rather than numerous small
sites.
4. Improved agency coordination.
5. Faster mitigation review may reduce perinit evaluation times.
6. Ensure successful wetlands compensation.
E. Defmitions:
1. BANK - wetland restoration or creation undertaken expressly for the purpose of
providing compensation for wedand losses from authorized City construction
activities. It includes only actual wedand restomtion or creafion established prior to
impacting another wedand as part of a credit program. Credits for existing wetland
functions may then be withdrawn from the bank to compensate for future individual
wetland impacts.
2. BANK SITE - property designated expressly for wedand restoration or creafion
for the purpose of providing compensation for wedand losses from future construction
acfivities. A bank site becomes a bank when the bank success criteria are met thereby
making credits available for withdrawal.
3. COMPENSATION - restoration or creation of wedands "pressly for the purpose
of fully offsetting project induced wedand losses after all appropriate and pmcficable
avoidance and minimizafion measures are achieved.
MEMORANDUM OF AGREEMENT 6
AND BANKING SYSTEM
4. - a process by which a group synthesizes its positions to
form a common collaborative agreement acceptable to all members.
5. CREATION - actions that estabtish wetlands from upland, non-wedand,
sites.
6. CREDIT - acreage or value given for successful wetland restoration and/or
creation that is part of a bank.
7. DE-BIT - acreage or value assigned to wetland impacts associated with a project
accepted for compensatory mitigation in accordance with this MOA.
8. FUNCTIONS - the physical, chemical and biological ecosystem processes of a
wetland without regard to their importance to society.
9. HYDROLOGIC-um - a designation describing the "sub-basin" of a watershed
established by the United States Geological Survey as displayed on hydrologic unit
maps. See WATERSHED.
10. IN-KIND - the replacement of a specific wetland class with the same class
such that the hydrologic and geomorphic conditions and the biotic components
are similar. This assures that the wetland being impacted is replaced by
MEMORANDUM OF AGREEMENT 7
WET'LAND BANKING SYSTEM
similar processes, structure and surface area.' The class is defined by the
U.S. Fish and Wildlife Service's Wetlands Classification System (Cowardin et
al. (1979)).
11. LEDGER - an accounting of credits and debits.
12. MITIGATION - the process includes:
(a) avoiding wetland impacts altogether by not taking a certain action or parts
of an action,
(b) minimizing wetland impacts by limiting the degree or magnitude of the
action and its implementation,
(c) rectifying the wetland impacts by repairing, rehabilitating, or restoring the
affected environment,
(d) reducing or eliminating the wetland impacts over time by preservation and
maintenance operations during the life of the action,
(e) compensating for unavoidable wetland impacts by replacing or providing
substitute resources or environments.
Brinson and Lee, 1989.
MEMORANDUM OF AGREEMENT 8
WETLAND BANKING SYSTEM
13. MMGATION REVIEW TEAM Gal) - a group of representatives from the
following organizations:
a. U.S. Army Engineer Norfolk District (Corps);
b. U.S. Environmental Protection Agency (EPA);
c. U.S. Fish and Wildlife Service (FWS);
d. National Marine Fisheries Service (NMFS);
e. Virginia Department of Environmental Quality (DEQ);
f. Virginia Department of Game and Inland Fisheries (VDGIF);
g. Virginia Marine Resources Commission (VMRC), ex officio;
h. Virginia Institute of Marine Science (VIMS), " officio; and the
i. City of Virginia Beach (City).
14. ON-SITE - located within or contiguous to the boundaries of the project site and
located within the same hydrologic unit. See Appendix A - Watershed Map.
15. PRACTICABLE - available and capable of being done after taldng into
consideration cost, existing technology, and logistics in light of overall project
purposes (40 CFR 230.3(g)).
16. RESTORATION - actions that re-establish functional wetlands on former
wetland sites.
MEMORANDUM OF AGREEMENT 9
WETLAND BANKING SYSTEM
17. VALUE - wetland attributes that result from or are influenced by wetland
structural factors and ecosystem functions and which are considered beneficial to
society.
18. WATERSHED - area or Tegion which drains to a river system or body of
water. See Appendix A, Watershed Map.
19. WETLANDS - those areas that are inundated or satumted by surface or
groundwater at a frequency and duration sufficient to support, and that under
normal circumstances do support, a prevalence of vegetation typically adapted
for life in saturated soil condifions. Wetlands generally include: swamps,
marshes, bogs, and similar areas.
U. POLJCY CONSIDERATIONS
The following legislation, directives and regulations govem construction and maintenance
activities in and near wetlands. This MOA is intended to comply with, including but not
limited to, the following authofifies:
A. Fedeml:
1. Clean Water Act (33 USC 1251, et seq.);
2. Rivers and Harbors Act of 1889 (33 USC 403);
MEMORANDUM OF AGREEMENT 10
WETLAND BANKING SYSTEM
3. National Environmental Policy Act (NEPA) (42 USC 4321, et seq.) and
implementing regulations;
4. Coastal Zone Management Act (16 USC 1451, et seq.);
S. Executive Order 11990; Protection of Wetlands;
6. Final Rule for Regulatory Programs of the Corps of Engineers (33 CFR Parts 320
through 330);
7. Final Rule; Clean Water Act Regulatory Programs (33 CFR Parts 323 and 328);
8. Section 404(b)(1) Guidelines for Specification of Disposal Sites for Dredged or
Fill Material (40 CFR Part 230);
9. Memorandum of Agreement dated February 6, 1990, between the Environmental
Protection Agency and the Department of the Army Conceming the Determination of
Mitigation Under the Clean Water Act, Secdon 404(b)(1) Guidelines;
10. The Fish and Wildlife Coordination Act (FWCA) (48 Stat. 401, as amended;
16 USC 661, et seq.),
I 1. Corps Regulatory Guidance letter 92-1 dated May 13, 1992,
12. Magnuson Fishery Conservation and Management Act (16 USC 1852)
(Amended November 28, 1990),
13. Habitat Conservation Policy for National Marine Fisheries Service (Federal
Register Vol. 48, No. 228, pp. 53142 - 53147).
B. State:
1. Title 28.2, Chapter 12, 13 and 14 of the Code of Virginia;
MEMORANDUM OF AGREEMENT I I
WETLAND BANKING SYSTEM
2. Chesapeake Bay Preservation Act (Fide 10, Chapter 21 of the Code of Virginia);
3. Open-Space Land Act (Tide 10, Chapter 17 of the Code of Virginia); and
4. The Virginia Water Protection Permit Regulation, VR 680-15-02, adopted
pursuant to State Water Control Law, Chapter 3. 1 of Title 62. 1.
IR. DUTEES AND RESPONSIB OF THE MRT
T'he MRT shall:
A. Evaluate and approve midgation bank site locations.
B. Evaluate and approve bank development plans and designate success criteria.
C. Develop a "crediting plan" which establishes a process or formula for determining
the credits available in a bank and a "debiting plan" for translating mitigation needs
into debits at a bank.
D. Evaluate and approve monitoring plans and reports, remediationplans and efforts,
and future activities as called for in the conser-vafion easement or restricting
covenants.
E. Evaluate and approve using bank sites for impacts in multiple hydrologic-units or
watersheds.
F. Determine when a bank is available for "change of debits and credits and
determine the number of credits available in a bank.
G. Review periodically the functioning of banks and update, in exceptional
circumstances, the available credits in banks.
MEMORANDUM OF AGREEMENT 12
WETLAND BANKING SYSTEM
H. Use the established debiting plan for translafing mifigation needs into debits on a
project by project basis.
1. Not meet without two-thirds (2/3) of the membership present. Meetings of the
MRT shall be held quarterly or as otherwise scheduled. At least 45 calendar days
written nofice of meefings shafl be provided to all MRT members.
J. Provide a 45 calendar day comment period after each meeting. Comments shall
be in writing.
K. Arrive at decisions by consensus.
The MRT shall reach a consensus decision(s) on the topics for which it has authority as
defined in this MOA. Tle MRT shall appoint a recorder who is responsible for documenting
each consensus decision and distributing such language to each MRT member for review.
There will be a 30 day comment period after each meeting during which members may
provide written comments. Maximum effort will be made to reach consensus of all members
of the MRT on all decisions referred to in this MOA. It is expected that the MRT may need
to have several discussions on issues untfl all views are discussed, and the group can develop
positions that afl members can at least agree to, if not totally support. If the MRT cannot
reach consensus on an issue, the dispute resolution process contained in Section IV -
DISPUTE RESOLUTION will be followed.
MEMORANDUM OF AGREEMENT 13
WETLAND BANKING SYSTEM
rV. DISPUTE RESOLUTION
In cases where the MRT members cannot reach consensus on an issue(s), the objecting
member(s) will provide a written statement to all members of the MRT indicating they do not
agree with the proposed consensus decision and request the issue(s) be elevated.
An informal elevation process will be followed, whereby representatives at higher levels of
the involved agencies will meet via telephone or conference to further discuss the issue(s)
and reach consensus. This dispute resolution phase will not extend beyond discussions
among the Regional Directors/Administrators of the FWS, NMFS, and EPA; the Division
Engineer of the North Atlantic Division; the Commonwealth of Virginia Secretmy of the
Natural Resources; and the Mayor, City of Virginia Beach.
Every attempt will be made to conclude the informal elevation process within 45 days of
written notification to the MRT. If a consensus decision on the elevated issue(s) cannot be
reached, credits from the mitigation bank under discussion shafl not be withdrawn unless an
altemate dispute resolution process can successfully resolve the issue(s).
V. LOCATION OF BANK S@ AND DEVELOPMENT OF BANKS
A. Proposed Sites: The City will attempt to locate within the City of Virginia Beach
individual bank sites that have the physical, chemical, and biological characteristics to
support wetland creation or restoration in watersheds where impacts are anticipated. Former
wetland sites, e.g., Prior Converted Cropland (PCC), shall be given high priority when
MEMORANDUM OF AGREEMENT 14
W'E7LAND BA?WNG SYSTEM
identifying potential bank sites. Proposals for mitigation banks shall be distributed to the
MRT and shall include documentation of the anficipated need for the bank, evaluation of
existing site conditions, and feasibility of wetland development on the proposed site. The
evaluation and approval of bank sites shall be accomplished on a case-by-case basis by the
MRT. The City shall strive to locate mitigation bwlk sites within each major watershed
where anticipated future wetland impacts may occur.
At the time of acquisition or designation of a bank site by the City, the City Council shall
authorize and cause to be recorded perpetual conservafion of the site in accordance with the
requirements and restrictive provisions of this MOA,
B. Bank Development: At such time that the City proposes to develop an approved site, a
bank development piwi shall be produced in coordination with the MRT.
T'he bank development plan shall include construction plans and design specifications
including grading, planfing, sods, and hydrology detail; and post-construction monitoring,
maintenance strategy, remediation provisions, success criteria, funding provisions, and other
informafion as agreed to by the MRT. The evaluation and approval of bank development
plans shall be accomplished on a case-by-case basis by the MRT.
MEMORANDUM OF AGREEMENT 15
WETLAND BANKING SYSTEM
The success criteria of each bank development plan should be based on such factors as
wetland hydrology, vegetative cover, vegetative diversity, water quality functions, wildlife
utility and others as determined by the MRT.
C. Monitoring: Post-construction monitoring of the bank shafl be performed by the City at
a minimum for 1, 2, 3, 5, 7 and 10 years and every five years afterward or until the success
criteria are achieved. Years I and 2 shall have, as a minimum, semi-annual monitoring.
Notice of a proposed monitoring schedule shall be given to the MRT at least 45 calendar
days in advance. Any member of the MRT may accompany City officials during the
monitoring. MRT members will notify the City, at least 5 calendar days prior to the on-site
visit, that they intend to be present.
Tlie City shall report in wrifing the results of monitoring to each MRT member. The MRT
will develop specific monitoring criteria for each bank in concuffence with the bank site
approval procedure. Monitoring plans shall include, at a minimum, permanent photo
stations, quantitafive vegetation sampling, and hydrology monitoring wells.
If remedial measures are necessary, the MRT will determine what measures will be
implemented and what maintenance tasks will be needed. Tbe City is responsible for
remedial measures such as re-grading and re-seeding, as well as maintenance tasks such as
fencing and sign posting in order to insure the tong-tem viability of the bank.
MEMORANDUM OF AGREEMENT 16
AND BANKING SYSTEM
D. Perpetual Conservation: The mitigation banks and bank sites shafl have public
ownership to ensure the long-term maintenance of the bank. After all credits in a bank are
debited by the MRT, in accordance with the provisions of Appendix B, a perpetual
conservation easement, held by an independent third party, shall be obtained and recorded by
the City, or the City may transfer the property in fee to a State or Federal agency or a non-
profit environmental conservation group that agrees to hold the property in perpetuity. See
Appendix B, Perpetual Conservation.
VI. USE OF BANKS AND BANK Srm
A. Project Applicability: The projects eligible for compensatory mitigation in accordance
with this MOA are those where the following conditions have been met:
1. there is no demonstrated practicable altemative to construction in a
wetland;
2. all practicable measures to mininiize wetland impacts are incorporated by
the project;
3. on-site mitigation of wetland impacts is not the preferred altemative; and
4. the proposed project will not be contrary to the public interest.
B. Use of Banks: This MOA allows the undersigned parties to meet the goals of the Clean
Water Act to restore and maintain the chemical, physical, and biological integrity of the
Nation's waters. When avoidance and minimization steps are taken and when on-site
MEMORANDUM OF AGREEMENT 17
AND BANKING SYSTEM
compensatory mifigafion is not practicable or preferable or cannot be provided effectively on-
site, credits from a bank may be used as determined by the regulatory permit review process.
C. Valuation of Debits and Credits: The impacted wetlands and banks may be evaluated by
the Wetland Evaluation Technique (WET), Habitat Evaluation Procedures (HEP), best
professional judgement, or other methods determined appropriate by the MRT. The NMT
will determine the number of credits available within a specific individual bank in accordance
with the specific individual bank crediting plan.
D. Exchange of Debits and Credits: Mifigation provided in accordance with this MOA is to
satisfy all pertinent laws, regulations and policies. No exchange of credit/debits will occur
until the MRT has determined the bank is operational. The minimum area of the
compensatory wetland mitigation shall equal the area of the wetlands being i,mpacted. It will
be determined during the regulatory permit review process for the City's proposed
construction project whether to require on-site compensatory mitigation or withdraw credits
from an approved mitigation bank. The regulatory pennit review process win determine the
mitigation needs for specific projects. Those mitigation needs will be converted by the MRT
into debits from a specific bank in accordance with the specific individual bank debiting plan.
E. Record Keeping: The City will establish and maintain the ledger to document the
activity of the wetland bank accounts with periodic audits conducted by the Corps. Ile MRT
and other interested agencies will be sent semi-annual statements documenfing the status of
MEMORANDUM OF AGREEMENT 18
WETLAND BANKING SYSTEM
the account. The ledger will be made available for review by any party participating in this
MOA upon written notice to the City.
Vii. IW ATION- MODHQCAIION AND ATION OF TEas
MEMORANDUM OF AGREEMERF
This MOA shall take effect when signed by representatives of the City of Virginia Beach, the
U.S. Army Corps of Engineers, and all participating signatory agencies. Modification of this
MOA requires the approval of all participating signatories. Modification may be proposed
by one or more signatories. Proposals will be submitted to the U.S. Army Corps of
Engineers, Norfolk District, for circulafion to all signatories for a ninety day review period.
Approval of the proposals will be indicated by written acceptance. A signatory may
terminate participation in this MOA by submitting written notice of intent to afl other
signatories 60 days in advance of the effecdve termination.
MEMORANDUM OF AGREEMENT 19
WETLAND BANKING SYSTEM
VIU. REIAIIONSHIP OF THIS MEMORANDUM OF AGREEMENT TO OTHER AUTHORMES
Nothing in this MOA is intended to diminish, modify, or otherwise affect the statutory or regulatory authorities
of the agencies involved.
City of Virginia Beach ate U.S. Anny Corps of Engineers Date
lames K. Spore Colonel Andrew M. Perkins, Jr.
City Manager District Engineer
U.S. Environmental Protection Agency Date U.S. Fish and Wildlife Service Date
Randy Pompino John P. Wolflin
Director, Environmental Services Division Supervisor, Chesapeake Bay Field Office
National Marine Fisheries Service Date Va. Department of Environmental Quality Date
Richard B. Roe Peter W. Schniidt
Regional Director Executive Director
Va. Dept. of Game and Inland Fisheries Date Virginia Marine Resources Co@ssion Date
William L.Woodfin (ex officio)
Acting Dii=tor William A. Pruitt
Commissioner
Virginia Institute of Marine Science Date
(ex officio)
Dennis L. Taylor
Dean/Director
Appendices:
A - Watershed Map
B - Perpetual Conservation
C - Operational Flow Chart
MEMORANDUM OF AGREEMENT
WETLAND BANKING SYSTEM 2 0
APPENDIX A WATERSHED MAP
A. BACKBAY
B. NORTHLANDINORNER
C. LAKE RUDEE
D. LYNNHAVEN SYSTEM
CREEK
MEMORANDUM OF AGREEMENT 21
WET'LAND BANKING SYSTEM
APPENDIX B - PERPETUAL CONSERVATION
A conservation easement held by an independent third party shall conserve perpetuafly the
mitiption bank site(s). The conservation easement shall run with the land and berome
included in the deeds, conveyance or transfer or grant documents. Ile conservation
easement shall outline expressly the limitation of the lands contained within the mitigation
bank.
The timitation of the lands shall prohibit discharging of fill, flooding, excavating, tree
cutting, removing vegetation, installing any structures, hunting or trapping or harvesting of
any plant or animal resources within the mitigation bank site except when authorized under
Federal and State law, and as approved by the MRT so that any requirements for
maintenance of the wetland shall continue to be safisfied.
T'he City may transfer the property in fee to a State or Federal agency or a non-profit
environmental conservation group that agrees to hold the property in perpetuity subject to the
foregoing prohibitions.
ne covenant that describes the easement for the niifigafion bank site(s) also shall be
displayed on those plat maps describing the property.
MEMORANDUM OF AGREEMENT 22
WETLAND MMGA71ON BANKING
APPENDIX C - OPERATIONAL FLOW CHART
MRT APPROVES
LOCATK)L STEP
i ES
MRT APPROVES
AND SLXCESS C
i E
MRT APPROVES M(
PLANS/REMEDIA-N
i ES
MRT EVALUA
SrrE SUCCE ss
i ES
MRT DEVELOPS C
& DEBrriNG P NO RE
i ES
MRT DETERN A
CREDRT A%o NU RESC
YES
UNRESOLVED DISPURE
PERMrr REV EW PROCESS 'r
COMPENSATION REQUIRED CREDrrS UNAVAILABLE
i FOR USE
OFFSrrE BANKING
RECOMMNDED
RESOURCE AGENCY RESOURCE AGENCY
CONCLJRRENCE DISPURE
i I
BANK USED OCESS
- 19 -
tem III-KI
CITY COUNCIL CONCERNS ITEM # 38396
ADD-ON
Council Lady Parker referenced the Ifampton Roads Planning District Commission proposal re increase
in gasoline tax by 5 cents per gauon. City Council unanipnously ADOPTED a Resolution opposing an
increase in the State's gasoline sales tax on November 23, 1993, and then did not have a consensus at
the HRPDC Meeting.
Council Lady Parker suggested there should be a consensus this time when attending the HRPDC
Meeting.
Councilman Moss requested Robert Maithias, Assistatit City Maitager, include in the City Council's
Legislative Package, the previous Resolution re gasoline tax.
September 20, 1994
- 20 -
c- I -K2
CITY COUNCIL coNcERNS ITEM # 38397
Council Lady Parker advised apparently JLARC is in the process of discussing recommendadons for
regional cooperation much stronger than throughout the State. Apparently a report was released last
Monday, September 12, 1994, from the Subcommittee with their initial findings. Council Lady Parker
requested a copy of this report be provided.
September 20, 1994
- 21 -
e- I- 3
CITY COUNCIL CONCERN,5 ITEM # 38398
Council Lady Parker referenced the Annual Long Term Debt Report. Pages 6 and 7 concern overall net
debt, Population growth and overall net debt capita capacity. 7he percentage jumps are quite substantial
versus the amount of population growth. 7he City should be careful concerning their debt ceilings and
what we have available versus the number of projectv. Perimeters have been established in the past,
September 20, 1994
- 22 -
e III - 4
CITY COUNCIL CONCERNS ITEM # 38399
Council Lady Parker referenced the correspondence of the Mayor to Congressman Pickett of August 2Z
1994, relative flow control legiviation.
Mayor Oberndorf advised as Chairman of SPSA for two years, and based on discussion with members
and legal counsel she was elicouraged to write to support legislation (House Bill 1056) which would
request existing localities in a regional Authority be given the opp()rtunity by federal law to continue their
operation. Mayor Oberndorf advised she did not represent the position of City Council in her
correspondence. Mayor Oberridorf advised if City Council desired a letter of clarification could be wriuen
to the Members of Congress that she did not represent the position of Council but her own position as
Chair of the SPS4. The budget for SPSA is predicated on a certain amount of solid waste being delivered
to their facilities. The recent Supreme Court case, that was decided on a very bad set of circumstances,
upsets the planning and bond financing that SP&4 has undertaken in good faith over the past years.
Without flow control, a considerable amount of the solid waste produced in this region will be diverted
to landfills on the Virginia Peitinsula and farther west in lirgiiiia.
Councilman Moss requested a copy of House Bill 1056 and a determination as to whether or not this Bill
might grant a monopoly itt perl)etuilv.
Councilman Dean advised .5P." had borrowed approxinwtely $4-MILLION to build a Materials
Recovery Facility and had not allc)wed the private sector to become involved in the bidding process as
apubliclprivate partnership. Recycled products are now being traded on the commodities market. For the
next decade, an incredible market is foreseen for recycled productv.
Mayor Oberndorf advised Sl'," has iiot decided on the building ()f the Materials Recovery Facility based
on the response of the City Couricil.
September 20, 1994
23 -
e
CITY COUNCIL coNcEpNS ITEM # 38400
Council Lady Henley refeenced the Resolution stating the City's endorsement of the concept adopted by
the 1994 General Assembly for the @ing of a cost-shaed Fed,,al Beach NOUrishment or Hurricane
PrOtection Project for the Sandbridge area,, an'4 declaring the City @ intent to become the local sponsor.
subject to the establishment of financing of the local share of such project thorough the creation of a
Specia Se ic District ( 0
1 rv e AD PTED June 7, 1994). 7he City Manager and City Attorney are to return to
City Council on September 27, 1994, with an ordinance establishing a Special Service Disttict in
Sandbridge.
Council Lady Henley advised approximately 88% of the Sandbridge residents, had signed the agreement
to be included in the Special Service District.
Concerning the funding plan, BY coNsENSUS, CitY Council concurred with Council Lady Henley's
suggestions of 6 cents incre-e on the real estate, 401@ on the lodging tax (phased 2% January 1995 and
2% January 1996, dedication of the TGIF lodging t4xes now collected from Sandbridge, and the tax
Profits from Little Island Parking Lot, the Fishing Pier, and Sandbridge Parking Lot to this funding.
The financial Package ad draft ordinances will be 5CIlFI)UIED for the CitY Council Sessio,, of
September 27, 1994.
September 20, 1994
- 24 -
- 6.
CITY COUNCIL CONCERNS ITEM # 38401
Councilman Baum distributed an advertisement from the Virginia-Pilot and the Ledger-Star, September
1 7, 1994, concerning a Home in Blackwater for sale with a one acre lot that was zoned for horses.
Councibnan Baum wished the City Manager and Director of Planning to pr(yvide information relative
houses with only an acre being allowed zoning for horses.
(.'ouncilman Baum advised Chesapeake requires a 3-acre minimum to have livestock an property.
September 20, 1994
- 25 -
CITY COUNCIL CONCERNS ITEM # 38402
Council Lady Strayhorn referenced the Interim Financial Statme,t. Fxpenses and Revenue can be taken
out of context. One should make sure they understand that in a system, either schools or general @,
You expend money in a different way. Expenditures may occur depending on whether a better purchase
may be made ie. school buses.
If Interim Financial Statements are discussed, the City Council should rwke sure that the public
understands that this does not mean a wrong was committed, because expenditures were indicated high
on an interim basis. Departmeiiiv, @chools or the Ge,,eral Fund should not be penalized.
,September 20, 1994
- 26 -
CITY COUNCIL CONCERNS ITEM # 38403
Co-@'lm- MOSS referenced the Ordinance to TRANSFER $ '700, 0 om h
Replacements (PrOject 1-058) to Ocean 1 610 f, SC 001, Re.-,io,,s ,,,d
Lakes High Sch-I (Project I -010) and Larkp,, Mddle
S,,h-I (project 1-053) repurcha es necessa open ose schoo
5, s rY to th is, in the Fall of 1994 (ADOPTED july
1994). Concerning the Interim Financial @tteent, Page 4.1, Councilinan Moss advised since Ocean
Lakes has opened, the crises has been resolved $1.2-MILLIoN was neededfor Ocean Lakes. $557,975
was unencumbered, Councilman oss was curio a to
funds remainitig aid wh Af us s the occurance that allowed the, to have these
at disposition would be m,de of heln
7he Director of Finance advised bet er price wer comp-ent. If the s em
i,, -rking, these unencumber(@d furi1 s c re(:cived on the techn,,Iogy sy t
d,y should be returned to Schools, Renovations and Replacements,
,5eptember 20, 1994
- 27 -
Item III-Y.9.
CITY COUNCIL CONCERNS ITEM # 38404
BY CONSENSUS, City Council Yhall SCHEDULE an Ordinance for the City Council Session of
September 27, 1994, relative moving the City Council InfonnallBriefing Sessions to the Conference
Room. Ihese sessions would be televised with the public in attendance and taped with a delayed
broadcast.
September 20, 1994
- 28 -
CITY COUNCIL CONCERNs ITEM # 38405
Council Lady Strayhorn advised she will not be in attendance during the City Council Session of
September 27, 1994, as she will be attending a business meeeting as a Commissioner with the Tidewater
Transportation District Commission.
September 20, 1994
- 29 -
e- I- ii.
CITY COUNCIL CONCERNS ITEM # 38406
Councibnan Branch referenced the Editorial in the Sunday Beacon of September 18, 1994, concerning
-o graffiti a@s from Virgina Beach being caught in Norfolk.
Ihe individuals advised they crossed the City lines as the graffiti laws are stricter in Virginia Beach.
Councilman Branch complimented the City and advised there is a backlog of calls to the Graffiti Hot Line.
Ae Southern ke Building which has been an eye sore for years has been painted.
September 20, 1994
- 30 -
Item III-K12.
CITY COUNCIL CONCEPJVS ITEM # 38407
Councilman Jones compli?nented the very positive and objective article on Burton Stadon in the
rirginianIPilot Ledger Star.
September 20, 1994
- 31 -
te- III-K13
CITY COUNCIL CONCERNS ITEM # 38408
Council Lady Strayhorn advised, concerning the Tidewater Transportation District Commission study on
light rail proposed through the Federal Transit Administration, this study delineates the rail line is going
to befrom Pembroke to downtown Norfolk. The total study amounts to $]-MILLION. $800,000 of which
is being paid by the Federal Transit Administration, $100,000 by the State PubLic Transit Fund and
$100,000 from 1-irginia Beach and Norfolk. 7he City of Virginia Beach would pay $25,000 this year and
$25, 000 next year. The line is to be approximately 1 7.7 miles.
Ihe TRT Commissioners voted to SUPPORT high speed radfrom Washington to Hampton Roads. Council
Lady Strayhorn advised she had a livt concerning the general scope of the work containing the cost
analysis, which we would be pleaved to provide.
Councilman Jones advised under the ISTEA legislation, local Transit Authorities are going to be involved
iti almost every major roadway project started or proposed A certain portion of the funding for those
major roads through VD07'is going t(i have to be used to study the Ix@,vsibility of public transit being an
alternative or supplemental sourcc ft)r transportation.
September 20, 1994
- 32 -
e- I-K]4.
CITY COUNCIL CONCEPJVS ITEM # 38409
As there are only four (4) Planning Items scheduled for the October City Council Sessions, these four (4)
Planning itenu will be advertised for the Evening Session, October 25, 1994.
September 20, 1994
- 33 -
e- I I-K .
CITY COUNCIL CONCEPNS ITEM # 38410
BY CONSENSUS, City Council Concerns shall be added to the weekly City Council Agenda.
@5eptember 20, 1994
34 -
te- I-L
ADJOURNMENT ITEM # 38411
Mayor Oberndorf DECL4PXD the City Council Meeting ADJOURNED at 5:00 P.M.
------------- -----
Beverly 0. Hooks, CMC
Chief Deputy City Clerk
---- ------ -------------------
,h Hodge @ti, C Meyera f,. Oberndorf
City Clerk Mayor
City of rzrginia Beach
Trirginia
September 20, 1994
'ICE OF TI@E CITY MANAGER MUNIC @AL CENREP
@8.) @@' 12V I @GINIA BE@C' VIRGINIA 2@56 @l
f A@ (80@) 427 @ 1 35
IDD (8N) @ll @305
October 14, 1994
The Honorable Mayor Meyera E. Oberndorf
and Members of City Council
Re: Pembroke Regional BMP (CIP 2-223)
Dear Members of City Council:
Attached is a memo from Mr. Smith to me transmitting additional
information documenting why an oil/water separator (water quality
inlet) was not used in conjunction with the wet pond for the
Pembroke Regional Best Management Practice (BMP) facility.
If you have any questions after reading the package, I will be
pleased to provide any additional information you may need.
With Pride in our City,
ames Y,. S
City Manager
JKS:SPS:gle
Attachment
City of Virginia Beach
INTER-OFFICE CORRESPONDENCE
October 14, 1994
TO: James K. Spore DEPARTMENT: Executive
FROM: Ralph A. Smith DEPARTMENT: Public Works
SUBJECT: Pembroke Regional BMP (CIP 2 223)
This is in response to the request by Councilman Moss at the September 20, 1994
City Council Meeting for additional information on the use of an oil/water separator.
Attached is a letter from our consultant engineer, Kimley-Horn Associates, addressing
the decision to use a wet pond without a water quality inlet (oil/water separator).
In summary, a water quality inlet provides moderate to high removal efficiency of
hydrocarbons (oil and grease). However, the trapped hydrocarbons may be flushed
through during heavy rains or multiple rain storm events.
Wet detention ponds provide high removal efficiency of hydrocarbons as well as a high
removal efficiency for suspended solids, lead, copper, cadmium, and bacteria. In
addition, a wet pond provides a moderate to high removal efficiency for total
phosphorus (the keystone pollutant established in the Chesapeake Bay Preservation
Act) and nitrogen.
In most cases, a wet pond is used to serve 10 acres and greater and water quality
inlets are recommended to serve high impervious areas of one acre and less. The
Pembroke BMP will serve a total of 51 acres, 30 acres currently developed and 21
frorn the undeveloped parcels. The size of a four foot deep water quality inlet to serve
the developed 30 acres is approximately 1 00 by 30 feet with an estimated cost of
$257,400 and to serve the undeveloped 21 acres is approximately 83 feet by 25 feet
with an estimated cost of $175,300.. The total estimated costs to provide water
quality inlets to the Pembroke Project is $432,700, iiot inCiLiding design and possible
acquisition costs.
James K. Spore
October 14, 1994
Page two
Re: Pembroke Regional BMP (CIP 2-223)
However, recognizing the benefit of a wet pond to treat the anticipated amount of
hydrocarbons in urban storm water runoff, the pond outlet structure was reviewed
with respect to preventing illicit discharges and disposal of oil and grease from being
discharged to Thalia Creek. In the process of developing this analysis, our consultant
engineer has identified the potential benefits of adding a skimmer to the outfall
structure as a means to help control illicit discharges. We currently have this concept
under review and, if we determine it would truly be a cost effective enhancement and
can be accomplished within available funds, we may pursue installation of such a
device.
I will be pleased to provide any additional information you may need.
Ralph 4. S@PIE.
Director
RAS/SPS/gle
Attachments
Kimley-Horn
and Associates, Inc,
Engineeiing
Planning
and
Environmenta)
Consultants
Suite 200
@ College Park Square
Virginia Beach, Viginia
October 11, 1994 23464-3609
Mr. Mark Johnson
City of Virginia Beach
Public Works Department
Municipal Center
Virginia Beach, Virginia 23456
Re: Pembroke Regional BMP
Water Quality Inlet
Dear Mr. Johnson,
The purpose of this letter is to document the reasons why a water
quality inlet was not included in the design of the Pembroke
Regional BMP.
As you are aware, the City of Virginia Beach identified a wet
detention pond as the best stormwater management facility for the
Pembroke Regional BMP. This decision was based on several
factors. Wet detention ponds can achieve a high removal efficiency
of several known urban pollutants, including both dissolved and
particulate types. For example, the keystone pollutant for the
Chesapeake Bay, total phosphorus, has inoderate to high removal
efficiency in a wet detention pond. Other pollutants such as
suspended solids, lead, copper, cadmium, bacteria, and oil and
grease have high removal efficiencies. A wet detention pond will
also provide stormwater runoff control by attenuating the 2-year and
10-year peak discharges. Additionally, landscaping can provide some
aesthetic value and passive recreation facilities can be included in
the design of this type of facility. By contrast, a water quality inlet
has a high removal efficiency for oil and grease, but minimal
removal efficiencv for m()st other pollutants. A water quality inlet
TEL 804 523 1439
FAX 804 523 169'
WIPGINIA BE
THE C:TY EN
Kimley-Horn Mr. Mark John@n, O.tober 11, 1994, Page 2
and Associates, Inc,
also provides very little stormwater runoff control and no aesthetic
value or recreational benefit.
The wet detention pond under construction as the Pembroke
Regional BMP serves approximately fifty acres of planned highly
impervious Central Business District property. Approximately 30
acres of tributary drainage area will be conveyed to the pond
through the Phase 1 66" reinforced concrete pipe (RCP) presently
under construction along Columbus Street. The remaining 20 acres
Of ttibutary drainage area will be conveyed to the pond upon design
and construction of the Phase 2 stormwater conveyance system along
Garrett Drive. The Phase 2 stormwater conveyance system is not a
part of the current construction, however the pond is being
constructed to its ultimate shape and size.
Consideration was given to the construction of a water quality inlet
at the end of each of the two pipes coming into the pond. This
would provide some pre-treatment for the oil and grease and keep
some of the pollutants from reaching the pond. In this case,
however, the water quality inlets were not included because of
upstream flooding concerns, the required size of the inlets, and the
cost associated with the addition of water quality inlets.
The energy losses, also known as head losses, through the water
quality inlet would have resulted in significant flooding potential
upstream during a 10 year design event. In order for the runoff to
move through thtee chambers and two submerged orifices, between
one and two feet of energy losses could be expected. These energy
losses would then cause runoff to back-up in the upstream
stormwater conveyance system. Specifically, flooding problems
would have occurred in the One Columbus Center and R/C
Theaters parking lots. This energy loss problem is typical for the
Tidewater area where the terrain is very flat and even small energy
losses are often a controlling factor in the design of
stormwater facilities. For the Pembroke Regional BMP, the energy
loss is magnified by the amount of runoff in the 66" RCP coming to
the pond in Phase 1. The water quality inlet would have to handle
the ten year discharge of 108 cubic feet per second from the 66"
RCP. A water quality inlet for the Phase 2 stormwater conveyance
system would have to handle the ten year discharge of approximately
100 cubic feet per second.
In addition to the flooding concerns the design of a water quality
inlet typicallv includes a permanent pool sized to provide a storage
volume of 460 cubic feet per acre ()f drainage area at a permanent
Kimley-Horn Mr. Ma,k John@n, October 11, 1994, Page 3
and Associates, Inc.
pool depth of four feet. This would require the permanent pool for
the Phase I water quality inlet to be approximately 100 feet by 30
feet in size and the Phase 2 water quality inlet to be approximately
83 feet by 25 feet in size. Even with this size, it is likely that
resuspension of sediments would occur. Water quality inlets are
normally used in locations with a one acre watershed, not 30 acre
watershed.
Finally, the estimated cost per acre of tributary drainage area for
building the water quality inlet is approximately $8,550. This
includes both the construction cost and the maintenance cost for the
first year. For the Phase I watershed a water quality inlet could be
expected to cost approximately $257,400. For the Phase 2
watershed a water quality inlet could be expected to cost
approximately $175,300.
Although a viable alternative i'n many circumstances, the decision
was made not to include water quality inlets in the design of the
Pembroke Regional BMP for all of the aforementioned reasons.
In addition to this letter, attached is a technical memorandum which
documents the many benefits of wet detention ponds and water
quality inlets. The memorandum also provides an explanation of the
nature of oil and grease pollution in urban stormwater runoff.
We trust that this letter addresses the concerns that have been
raised and we hope that the technical memorandum will be of
assistance in making future policy decisions concerning stormwater
management facilities and the removal ()f oil and grease pollution
from urban runoff. If there are any questions please do not hesitate
to contact us.
Sincerely,
AND ASSOCIATES, INC.
esigner
I
L
E., Principal in Charge
Technical Memorandu,
on the
RE@OVAL OF OIL AND GREASE POLLUTION FROM
UR-BAN STOPMWATER RUNOFF
Prepared for:
Citv of Virginia Beach
Public Works Department
Municipal Center
Virginia Beach, Virginia 23456
Prepared by:
Ki-ley-Horn and Associates, inc.
6465 College Park Square, Suite 200
Virginia Beach, Virginia 23464
October 1994
Introduction
This technical memorandum describes the nature of oil and grease pollution in urban
stormwater runoff. Also included are descriptions of the benefits of a wet detention
pond and a water quality inlet. Finally, the two stormwater management facilities are
compared to determine their respective applications in providing regional stormwater
management. This information may assist the City of Virginia Beach in the decision-
making for planning additional regional stormwater management facilities.
1
Oil and Grease
Oil and grease pollution, known more specifically as hydrocarbons, can be found in almost
all urban stormwater runoff. It is most prevalent in the runoff from parking lots, roads,
service stations, and industrial sites due to the high number of vehicles being operated on
these properties. These vehicles often leak oil or leave other greasy residues on the
pavement which are then transported to the stormwater conveyance system during a rainfall
event. New pavement can increase the oil and grease pollutant loading by leaching
hydrocarbons to the stormwater conveyance system during a rainfall event. The cumulative
affect of these available pollutants is a low concentration of hydrocarbons in urban
stormwater runoff which is known to be toxic to aquatic life'. Average bydrocarbon
concentrations during storm events have been reported to range from 2 mFA to 10 mg/i2.
This low concentration of hydrocarbons should not be confused with high-concentration oil
slicks that may result from an oil spill or the illegal disposal of waste oil. Oil spills are
accidental and unpredictable and the illegal disposal of waste oil into storm sewers in
residential neighborhoods can be a local problem@. These high concentrations of
hydrocarbons have a well documented history of producing catastrophic damage to the
environment. The clean up effort often takes years and the affected ecosystem may never
fully recover. For the pur-poses of this memorandum, however, onlv low concentration
hydrocarbons typically found in urban stormwater runoff will be addressed.
Hydrocarbons can be categorized in two principal subgroups: aliphatic and aromatic.
Aliphatic hydrocarbons are the least persistent of the hydrocarbons because of their high
volatility and solubility. Aromatic hydrocarbons tend to partition to organic matter. resist
degradation, and persist in the aquatic environment.
1 Thomas R. Schueler, Controlling Urban Runoff, Metropolitan Washington Council of Governments,
June 1987, p. 1.7.
2 Schueler, p. 1.7.
3 J.A. Arnold ed., D.E. Line, S.W. Coffey, and J. Spooner, 1993 Stormwater Management Guidance
Manual, North Carolina Cooperative Extension Service and North Carolina Division of Environmental
Management, Raleigh, NC, p. 2.6
2
It is the persistence of the aromatic hydrocarbon that makes it the pollutant with the
greatest negative impact on the water quality of the receiving waters. Several monocyclic
aromatic hydrocarbons such as benzene and toluene, even at low concentrations, are toxic
to fish, invertebrates, and algae. Several polycyclic aromatic hydrocarbons (PAHS) are also
toxic to aquatic organisms at low concentrations ranging from 0.2 to 10 Mg/l 4. This toxicity
tends to increase with the increasing molecular weight and concentration of the PABS.
Unfortunately, the precise impacts of the many different types of hydrocarbons are not well
understood, since few toxicity tests have been performed in the field. Testing is largely
confined to laboratory exposure tests for specific hydrocarbon compoundS5. This lack of
adequate field data makes it difficult to quantify the nature of hydrocarbon loads in urban
stormwater runoff and difficu'It to deter-mine the best stormwater management facility with
which to treat the hydrocarbons.
This lack of adequate field testing was also considered in identi@ng total phosphorus as the
keystone pollutant for the Chesapeake Bay regulations. Oil and grease were listed as
pollutants with a well-defined impact on the Bay. However, not enough research data exists
to provide an adequate basis by which to estimate the change in oil and grease loads in
response to land development and in response to the installation of stormwater management
facilities.
Low concentration hydrocarbons in urban stormwater runoff can be removed through the
use of several different types of stormwater management facilities. Two of the stormwater
management facilities which have a high pollutant removal efficiency for hydrocarbons are
a wet detention pond and a water quality inlet.
4 Hazardous Waste Management, Environmental Resources Management Group, McGraw Hill, Inc.,
1994. p. 301.
5 Thomas R. Schueler, Controlling Urban Runoff, Metropolitan Washington Council of Governments,
June 1987, p. 1.7
3
Wet Detention Pond
If properly designed and maintained, a wet detention pond is one of the most beneficial
multi-use stormwater management facilities in use. It is typically used to treat any watershed
which is at least 10 acres in size since smaller watersheds make it difficult to maintain the
permanent pool unless there is a natural spring within the watershed6. Wet detention
ponds are also recommended for watersheds larger than 10 acres since pollutant removal
increases as the permanent pool size is increased. This is true up to a certain size, at which
point the pollutant removal does not continue to improve with increased permanent pool
size 7.
In the City of Virginia Beach, the permanent pool size is contingent on the land uses in the
watershed. For example, the water quality volume for the Pembroke Regional BMP was
calculated as 1.6 inches over the 50.6-acre watershed due to the highly impervious nature
of the planned Central Business District (CBD)8. This criteria required a permanent pool
of 293,885 cubic feet, which is approximately a one acre permanent pool with an average
depth of 6.5'.
An optimally designed wet detention pond will provide stormwater runoff control, pollutant
removal, and other tangential benefits as described below.
Stormwater Runoff Control
Stormwater runoff control is often referred to as water quantity treatment. Wet ponds
provide several stormwater runoff control benefits. They can be designed to control the
post-development peak discharge rate for larger storms by attenuating flows to the pre-
development level. For example, a wet detention pond designed in the City of Virginia
Beach is required to reduce the post-development peak discharge rate for the 2-year and
10-year design events, considered independently, to pre-development levels. Wet detention
ponds do not significantly reduce the volume of water discharged, since all runoff is
eventually released following a rainfall event. The only runoff volume lost is through
6 Schueler, p. 4.10
7 Schueler, p.4.40
8 PublicWorksDesignGuideforStormwaterManagementandtheUseofBMPsintheCityofVirginia
Beach, City of Virginia Beach Public Works Department, March 1990, p.17
4
evaporation and infiltration9- Some groundwater recharge will occur by way of infiltration
from the pond's permanent pool to the surrounding side slopes and pond bottom. The
permanent pool will, however, maintain a water level driven by surrounding water table
fluctuations thus preventing any significant infiltration from occurring. Downstream erosion
control is provided through attenuation of the peak discharge rate for all rainfall events
which create a bankfull situation in the downstream water body.
Pollutant Removal
Pollutant removal is accomplished in a wet pond through sedimentation, chemical reactions,
and biological processes. The pond is designed to have incoming storm runoff displace the
existing water in the pond's permanent pool. The storm runoff will then remain in the
permanent pool until it is displaced by runoff from a subsequent storm event. This
treatment methodology provides for high removal efficiency of hydrocarbons, suspended
solids, lead, cadmium, copper and bacteria. Moderate removal efficiency can be expected
for total phosphorus, total nitrogen, organic matter, alid zinclo.
While in the pond, the suspended solids, lead, particulate phosphorus, particulate nitrogen,
and some organic matter will settle out of the water column through sedimentation and
accumulate on the bottom of the pond". The larger, heavier pollutants (such as lead) will
settle out of the water column first, while the smaller, lighter pollutants (such as organic
matter) will take longer to settle out. Some hydrocarbons, such as transmission fluid, are
heavier than water and also will tend to settle out of the water column.
Some hydrocarbons are lighter than water and will initially rise and form a rainbow-colored
film on the water's surface. Tbe hydrocarbons will then chemically react witb the suspended
solids and debris through precipitation, sorption, chemical oxidation-reduction, and
ionization. Once attached to the heavier suspended solids and debris, the hydrocarbons can
settle out of the water column. Zinc, bacteria, soluble phosphorus, and soluble nitrogen will
9 Tbomas R. Schueler, Controlling Urban Runoff, MetTOpolitan Washington Council of Governments,
June 1987, p.4.2
'o i.A- Arnold ed., D.E. Line, S.W. Coffey, and J. Spooner, 1993 Stormwater Management Guidance
Manual. North Carolina Cooperative Extension Service and North Carolina Division of Environmental
Management, Raleigh, NC. p.4.21
" ThomasR.Schueler,ControllingUrbanRunoffMetropolitanWashingioncouncilofGovernments,
June 1987, pp.3.11-3.14
5
also chemically attach to suspended solids and debris and settle out of the water column 12.
One example of the chemical reactions that naturally occur in urban stormwater runoff was
provided by Lee Stimpson, the Watershed Protection Engineer for Guilford County, North
Carolina. Mr. Stimpson took a jar sample of the runoff from an 8-acre truck stop during
a rainfall event. The sample initially developed a rainbow-colored film on the surface. Over
a period of several days, the oily film slowly disappeared from the surface and sediment
accumulated in the bottom of the jar 13.
Biological processes will also occur in the pond due to the presence of aquatic plants, algae,
and bacteria. They wfll remove some nutrients in soluble form through sorption. Other
soluble nutrients will be removed through biological uptake where the plants consume the
nutrients as part of the normal growing process 14.
Biological processes will also help remove some of the hydrocarbons from the pond's surface
through volatilization. This natural process is a type of evaporation in which the
hydrocarbons are eliminated from the stormwater system. This biological process can also
be used in the treatment of hydrocarbons which are found in contaminated soil. The
treatment is known as bio-venting, since air is vented through the soil to stimulate and
accelerate the biological processes 15.
12 i.A. Arnold ed., D.E. Line, S.W. Coffey, and J. Spooner, 1993 Stormwater Management Guidance
Manual, North Carolina Cooperative Extension Service and North Carolina Division of Environmental
Management, Raleigh, NC, pp.2.2-2.8
13 Lee Stimpson, Guilford County Watershed Protection Engineer, Guilford County, North Carolina,
Personal Communication, September 1994.
14 J.A. Arnold ed., D.E. Line, S.W. Coffey, and J. Spooner, 1993 Stormwater Management Guidance
Manual, North Carolina Cooperative Extension Service and North Carolina Division of Environmental
Management, Raleigh, NC.
15 Danny Averett, U.S. Army Corps of Engineers, Waterways Experiment Station, Vicksburg,
Mississippi, Personal Communication, September 1994
6
Other Considerations
There are many other considerations in the use of a wet detention pond. Wet ponds can
be designed to offer aesthetic and recreational beneflts. For example, the Pembroke
Regional BMP includes perimeter landscaping and a one-quarter mile heart traivwalkway.
Wet ponds were also the preferred stormwater management facility in separate surveys in
Maryland. Residents felt that a pond enhances property values, adds to the appearance of
the community, and promotes a sense of communityl7. Concems were also raised in the
surveys about safet7y, mosquitos, odor, turbidity, and algae problems. However, on the
whole, most people favored the benefits of a wet pond over the temporary nuisances 18.
Wet ponds may also be designed to have rish and wildlife populations or created wetland
areas.
The wet detention pond can be modified to deal with the high concentrations of
hydrocarbons from oil spills and illegal dumping. A submerged plate (skimmer) or inverted
elbow pipe could be physically attached to the outlet structure or supported in the
surrounding embanlanent. This would require any water discharged through the outlet
structure to be drawn from the middle of the pond's water column and would contain any
floatable debris and hydrocarbons in the wet detention pond. If a high concentration of
hydrocarbons is introduced to the pond, untreated hydrocarbons will remain floating in the
vicinity of the outlet structure and produce an oily sheen. This will be noticed by visual
inspection and an investigation as to the source of the unusually high concentration of
hydrocarbons can be undertaken. Also, if an oil spill occurs in the watershed the
hydrocarbons will collect and remain in the wet detention pond. This will facilitate easier
clean-up and reduce damage to the receiving waters. A skimmer constructed from an
aluminum or stainless steel plate can be expected to cost less than $1,000. The major
disadvantage to a metal skimmer, however, is it detracts from the aesthetic beauty of the
outlet structure. If aesthetics are an issue, the skimmer should be constructed of similar
material and quality to the outlet structure. For example, the concrete outlet str-ucture in
Pembroke BMP might require a concrete skimmer which could cost approximately $4,000,
but would maintain the aesthetic quality of the outlet structure.
17 Thomas R. Schueler, Controlling Urban Runoff, Metropolitan Washington Council of Governments,
June 1987, p.4.19
18 Schueler, p.4.19
7
Maintenance
Wet detention ponds require routine inspection and maintenance after rainfall events. This
maintenance should include removal of debris and repair of any erosion damage. Mowing
and mosquito control should also be accomplished through routine, scheduled maintenance.
Non-routine maintenance will include structural repairs and sediment removal. Structural
repairs to the inflow pipes, outlet structure, and skimmer may be required after particularly
large rainfall events; sediment removal may be required every 10 to 20 years, although the
actual sediment removal schedule will depend on the size of the pond and the rate of
sediment accumulation on the bottom'9. Disposal may include to)dcity testing and
hazardous waste removal technologies.
Costs
Construction of the Pembroke Regional BMP, not including the conveyance system
improvements, was accomplished at an approximate cost of $7,000 per acre of service area.
This does not include any costs for land acquisition. An additional 3-5% should be budgeted
annually for required maintenance activities2o. Therefore, the total cost for a wet detention
pond is estimated to be approximately $7,300 per acre of service area.
19 Schueler, p.4.15
'o Schueler, p.4.15
8
co
a,
a,
CD
F-
Water Quality Inlet
The water quality inlet, also known as an oil-water separator or an oil-grit chamber, takes
on many different shapes and sizes. It is typically designed to remove both sediment and
hydrocarbon loadings from highly impervious watersheds of up to one acre in size2l. It
does not offer much stormwater r-unoff control or other tangential benefits.
Stormwater Runoff Control
Water quality inlets typically provide little or no stormwater runoff control because of their
limited storage capacity. To reduce the peak discharge rate, control the volume of runoff
from a large stor-m event, or control erosion during bankfull conditions, a significantly larger
volume of runoff would h@ive to be detained than is tvpically provided in a water quality
inlet.
If stormwater runoff control was desired in a water quality inlet, the design might then
require several water qualitv inlets or an underground detention vault system with special
desigD provisions to match the pollutant removal capability of a typical water quality inlet.
Underground stormwater runoff control is feasible but very expensive; consequently, water
quality inlets are primarily designed to provide some pollutant removal.
Pollutant Removal
Pollutant removal is typically accomplished in a water quality inlet through the use of a three
chambers. The first chamber includes a trash rack to trap litter and debris as well as a
permanent pool to trap large suspended pollutants through sedimentation. The second
chamber typically discharges through an inverted elbow pipe or submerged weir, which draws
water from the middle of the permanent pool's water column. This will convey runoff that
does not include the hydrocarbons and other floatables on top of the water22. The
hydrocarbons will then chemically react with suspended solids and debris through
precipitation, sorption, chemical oxidation-reduction, and ionization and settle out of the
water column. This is similar to the chemical reaction described for a wet detention pond.
The water quality inlet, however, will not significantly benefit from the biological processes
21 Thomas R. Schueler, Controlling Urban Runoff, 1,4etropolitan Washington Council of Governments,
June 1987, p. 8.6
22 Schueler, p. 8.2
10
described for a wet detention pond due to the absence of aquatic plants and algae. The
third chamber connects the water quality inlet to the storm drain outlet.
The permanent pool size requirement must be examined more closely when evaluating the
pollutant removal efficiency of a water qual4 inlet. Standards for the permanent pool size
vary throughout the available design manuals from 200 cubic feet per acre" to 400 cubic
feet per acre 24 - For the purposes of this technical memorandum, a permanent pool size
of 400 cubic feet per acre is used. This is only 0. I 1" of runoff over the watershed, whereas,
most wet detention ponds are designed with a permanent pool volume of approximately
1.50" of runoff over the watershed which is approximately 14 times as large. The permanent
pool depth of a water quality inlet is typically 4 feet whereas a wet detention pond varies
from 3 to 15 feet. Sediment'ation is enhanced when a stormwater management facility is
dCSigDed with a permanent pool size and depth large enough to inhibit resuspension of the
settled pollutants25- This may not be the case in the small permanent pool required for
a water quality inlet. Sediment effectively deposited during small storms may become
resuspended if not removed from the inlet prior to a large storm. The only way of
permanently removing the pollutants from a water qualitv inlet is through regularly
scheduled cleaning and removal of the sediment. Furthermore, since the water quality inlet
has a small permanent pool, the average detention time of runoff during most storms will
seldom exceed one hour as the riinoff moves through tlie inlet26.
The small required size of a permanent pool in a water quality inlet can seem very large
when applying the size requirements to a regional watershed. For example, the permanent
pool required for each of tbe two storm sewer pipes for tbe Pembroke Regional BMP (50.6
acre watershed) would have to be 12,000 cubic feet is size and 8,200 cubic feet in size. At
a standard permanent pool depth of 4 feet, the permanent pool areas would be 100 feet by
30 feet and 82 feet by 25 feet. These required sizes are much larger than standard storm
sewer inlets and would be expensive to build and difficult to maintain.
23 BestManagementPracticesDesignGuidanceManualforHamptonRoads,HamptonRoadsPlanning
District Commission, December 1991, p. 141
24 Thomas R. Schueler, Controlling Urban Runoff, Metropolitan Washington Council of Governments,
June 1987, p. 8.2
25 Schueler, p. 8.2
26 Schueler, p. 8.5
11
Other Considerations
There are many other considerations in the use of a water quality inlet. It is an
inconspicuous stormwater management facility that hides trapped pollutants from plain view,
This is advantageous in some circumstances where public acceptance is critical. However,
there are no appreciable aesthetic or recreational benefits derived from a water quality inlet.
The most significant environmental attribute is the trapping of large sediment and
hydrocarbons in a sealed chamber. This effectively eliminates the migration of these
pollutants into the surrounding ground through groundwater recharge.
It is also important to note th'at the pollutant removal efficiency in a water quality inlet has
not been adequately field tested, and so remains largely a matter of speculation. The lack
of field testing 17 should be considered in conjunction with the aforementioned
disadvantages when choosing a water quality inlet for treatment.
Maintenance
Water quality inlets require routine inspection and maintenance after rainfall events.
Maintenance should include removal of debris and sediment and any necessary repairs to
the structure. The City of Virginia Beach currently cleans its water quality inlets four times
a year. Maintenance records indicate that an increase to once every six weeks would be
beneficial28.
Disposal may include to)dcity testing and hazardous waste removal technologies. If the
sediment is not to)dc, it may be removed by pumping the contents out of the chamber as a
slurry mix and then sending it to a wastewater treatment plant. The sediment may also be
removed by carefully siphoning out the water into some nearby vegetated area and then
manually removing the sediment for transport to a solid waste facility 29.
27 Schueler, p. 8.1
28 CityofVirginiaBeachPublicWorksDepartment,VirginiaBeach,Virginia,PersonaiCommunication
@th Staff, October 1994
29 Thomas R. Schueler, Controlling Urban Runoff, Metropolitan Washington Council of GoveTnments,
June 1987, p. 8.8
12
Costs
The estimated construction cost for a standard three-chamber water quality inlet designed
to treat a one acre watershed can be estimated at $8,00030. This does not include any
costs for land acquisition. The maintenance cost depends closely on the to3dcity of the
material being removed and the required disposal method. The maintenance budget for
quar-terly maintenance of the 40 city-maintained water quality inlets is $22,000 annually,
This comes to an annual maintenance cost of $550 for each water quality inlet. Therefore,
the total cost of a water quality inlet which treats a one acre watershed is estimated to be
$8,550.
30 Schueler, p. 8.8
31 CityofVirginiaBeachPublicWorksDepartment,VirginiaBeach,Virginia,Personalcommunication
@th Staff, October 1994
13
F- 00
c
c c CY V)
4)0 0
cc u E-=
F-
LL
0 E
> CL
o 13
E0
M
(D
oLt)
U=
L)
<
V) 0
m
F%
iz
0
c-
CJ LL
E c
m
0 E U 2 cL
c C:, C el
0 0 v
OU<o
Conclusions
There is no question that even low concentrations of hydrocarbons contribute to the urban
stormwater runoff pollution problem. Oil and grease were listed in the Chesapeake Bay
Guidance Calculation Procedures as pollutants with a well-defined impact on the Bay.
Hydrocarbons are also listed as typical urban stormwater runoff pollutants in most
stormwater management publications and water qual@ monitoring reports.
This technical memorandum concentrates on the removal of hydrocarbons and other
pollutants in a wet detention pond and a water quality inlet for which three conclusions can
be drawn. The conclusions c'oncern the compar-ison of a wet detention pond and a water
quality inlet, the use of a water quality inlet as pre-treatment for a wet detention pond, and
the use of a skimmer in a wet detention pond.
Comparison of a Wet.Detention Pond and a Water Qualitv Inlet
Either a wet detention pond or a water quality inlet will effectively remove some of the low
concentration hydrocarbons found in urban stormwater runoff. A comparison of these two
types of stormwater management facilities is provided in the table on the following page.
This comparison shows that a wet detention pond provides high removal efficiency for many
urban pollutants, whereas the water quality inlet provides high removal efficiency for only
hydrocarbons. Furthermore, sedimentation is more effective in a wet detention pond than
in a water quality inlet due to the permanent pool in the pond typically being appro)dmately
14 times as large and over twice as deep as the permanent pool in a water quality inlet.
Finally, removal of pollutants through biological processes such as volatilization and
biological uptake is only expected to occur in a wet detention pond. Tlis comparison clearly
shows that the wet detention pond is the preferred stormwater management facility.
15
COMPARISON OF WET DETENTION POND AND WATER QUALITY INLET
KF-Y ISSUE @T DETENTION POND WATER QUALITY INLET
Service Area 10 acres and larger 0-2 acres
Permanent Pool 1.60' over the 0.11' over the
Volume drainage area drainage area
Peak Discharge Control 2-Year and Minimal
Control 10-Year Peak
Volume Control Minimal None
Groundwater Minimal None
Recharge
Erosion Control Moderate Minimal
Pollutant Removal Hydrocarbons Hydrocarbons
Efficiency Suspended Solids
(High) Lead
Bacteria
Pollutant Removal Total Phosphorus No Data
Efficiency Total Nitrogen
(Moderate) Organic Matter
Zinc
Pollutant Removal No Da La Suspended Solids
Efficiency I-ead
(I,ow) Bacteria
Zinc
Organic Matter
Aesthetic Benefit Undscaped None
Recreational Passive Recreation None
Benefit Potential
Public Acceptance Increase Property Value Inconspicuous
Environmental Wildlife/Fish Habitat Wetland No Groundwater
Attributes Creation Contamination
Maintenance Remove Debris Remove Debris
Erosion Control Routine Inspections
Routine Inspections
Mowing
Mosquito Control
i ent Removal Every 10 Years Everv 3 Months
First Yt S7,300 per acre served $8,550 per acre served
Facility (
16
Use of a Water Ouality Inlet for Pre-Treatment
Consideration should be given to tbe construction of a water quality inlet at the end of the
pipe coming into a wet detention pond. This would provide some pre-treatment for the oil
and grease and keep some of the pollutants from reaching the pond. During design of the
Pembroke Regional BMP, however, three major obstacles were uncovered regarding the use
a water quality inlet as a regional pre-treatment device. These obstacles are upstream
flooding concerns, the required size of the inlet, and the high cost associated with the
addition of a water quality inlet to the design.
The energy losses (also known as head loss) through the water quality inlet may result in
significant flooding potential upstream during a 10-year design event. In order for the r-unoff
to move through three chambers and two submerged orifices, an estimated one to two feet
of energy losses can be expected. These energy losses will cause runoff to back-up in the
upstream stormwater convevance system. Flooding problems may occur in parking lots and
other low lying parts of the watershed.
This energy loss problem is tvpical for the Tidewater area where the terrain is very flat and
even small energy losses are often a controlling factor in the design of stormwater facilities.
For the Pembroke Regional BMP the problem was magnified by the amount of runoff in
the 66" reinforced concrete pipe (RCP) coming to the pond. The water quality inlet would
have to handle the 10-year discharge of 108 cubic feet per second from the 66" RCP.
Typically, water quality inlets are only designed to handle the discharge from up to one acre
of a highly impervious watershed. Special design details would have to be developed to
facilitate the use of a water quality inlet for the large discharge typical for a regional BMP.
The design of a water quality inlet typically includes a permanent pool sized to provide a
storage volume of 400 cubic feet per acre of drainage area at a permanent pool depth of
4 feet, not a practical size for a regional BMP with greater than a 10 acre watershed. For
example, the water qualitv inlet for the 66" reinforced concrete pipe presently under
construction for conveyanc e of runoff to the Pembroke Regional BMP would have to be
appro)dmately 30 feet by 100 feet in size.
Finally, the estimated cost per acre for a water qualitv inlet is approximately $8,550. This
estimate includes both the construction cost and the maintenance cost for the first year.
This estimated cost per acre for a water quality inlet is higher than the estimated cost per
acre of approximately $7,300 for a wet detention pond for the first year. For the Phase 1
pipe to the Pembroke Regional BMP (30.1 acre watershed) a water quality inlet would cost
17
approximately $257,400. For the Ph,,e 2 pipe to the Pembroke Regional BMP (20.5 acre
watershed) a -ater qualitv inlet would cost approximately $175,300. 'nis cost should be
carefully considered since the removal of hydrocarbons can be accomplished by the wet
detention pond already under construction.
Although a viable alternative in some circumstances, the use of water quality inlets as pre-
treatment for a regional BMP may be difficult. Water quality inlets become large and
expensive for watersheds greater than 10 acres. They are also unnecessary when a wet
detention pond will provide treatment of many urban pollutants, including low
concentrations of hydrocarbons.
Use of a Skimmer in the Pond
One of the primary advantages of a water quality inlet is its ability to hold hydrocarbons and
other floatables. This could be accomplished in a wet detention pond through the use of a
submerged plate (skimmer) or inverted elbow pipe at the outlet structure. The device can
be pbvsically attached to the outlet structure or supported in the surrounding embankment.
The skimmer would hold tloatable debris in the pond and allow tloating hydrocarbons to
remain on the surface of the wet detention pond until they are manually removed, attach
to sediment and settle out of the water column, che@cally react, or are removed through
biological processes.
Manual removal of hydrocarbons may become necessary if high concentrations are
introduced to the system through illegal dumping or an oil spill. The primary advantage of
using a skimmer is this opportunity to remove a high concentration of hydrocarbons, which
might have oth@se managed to avoid treatment in the wet detention pond. The primary
disadvantages are the increased maintenance requirements, including routine cleaning and
repairing of any damage to the skimmer, as well as the unattractive nature of most skimmers
currently in use. Aesthetics of the skimmer can be enhanced, however, by constructing one
with the same materials used to construct the outlet structijre.
18
BIBLIOGRAPHY
Amold, J.A. ed., D.E. Line, S.W. Coffey, and J. Spooner, 1993 Stormwater
Management Guidance Manual. North Carolina Cooperative Extension Service and North
Carolina Division of Environmental Management, Raleigh, NC.
ASCE Stormwater Detention Outlet Control Structures, Final Report of the Task
Committee on the Design of Outlet Structures, American Society of Civil Engineers, New
York, 1985.
Averett, Danny, U.S. Army Corps of Engineers, Waterwavs Experiment Station,
Vicksburg, Mississippi, Personal Communication, September 1994.
Best Management Practices Design Guidance Manual for Hampton Roads, Hampton
Roads Planning District Commission, December 1991.
City of Virginia Beach Public Works Department, Virginia Beach, Virginia, Personal
Communication with Staff, October 1994.
Eaker, William M.. Stormwater Management in North Carolina, Land-of-Skv
Regional Council, Februarv 1994.
Goode, Bob, ViTginia Department of Environmental Quality, Tidewater Office,
Personal Communication, September 1994.
Hazardous Waste Management, Environmental Resources Management Group,
McGraw Hill, Inc. 1994.
Kaighn, Robert J. Jr., University of Virginia, Charlottesville, Virginia, Personal
Communication, September 1994.
Malcom, H.R., P.E. Efficiency-Based Design of Stor-mwater Settling Ponds, one-day
workshop, North Carolina State University, May 4, 1993.
Meiers, Damon, South Florida Water Management District, Surface Water
Permitting, West Palm Beach, Florida, Personal Communication, September 1994.
Public Works Design Guide for Stormwater Management and the Use of BMPs in
the City of Virginia Beach, City of Virginia Beach Public Works Department, March 1990.
Rossmiller, Ronald L., How to Design Cost-Effective Storm Water Detention
Facilities, ASCE Continuing Education Seminar notes, April 15-16, 1991.
Schueler, Thomas R., Controlling Urban Runoff - A Practical Manual for Planning
and Designing Urban BMPS, Metropolitan Washington Council of Governments, June 1987.
19
SFWMD Management and Storage of Surface Waters - Permit Information Manual -
Volume IV, South Florida Water Management District, November 1987.
Stimpson, Lee, Guilford County Watershed Protection Engineer, Guilford County,
North Carolina, Personal Communication, September 1994.
Stimpson, Lee D., Water Quality Protection Manual - Second Edition, Guilford
County Planning and Development Department, Office of the Soil Scientist, Greensboro,
North Carolina, January 1994.
Truong, Hung V., Collin R. Burrell, Mee S. Phua, and Renette Dallas, Application
of Washington D.C. Sandfilter for Urban Runoff Control, District of Columbia Department
of Consumer and Regulatory Affairs, Environmental Regulation Administration, Soil
Resources Management Division, Stormwater Management Branch, March 1993.
Wilkening, Hal, SJR Design Criteria and Guidelines for Wet Detention
Treatment Systems, Memorandum - St. Johns River Water Management District, April 19,
1990.
Yu, Shaw L. Ph.D. and Robert J. Kaighn, VDOT Manual of Practice for Planning
Stormwater Management - Final Report, Virginia Transportation Research Council, Januarv
1992.
20