MEM MORANDU UM To: Jason Wid dstrom, P.E. From: Doug Beisc ch, P.E. Departmen nt of Public W Works J. Alex Fora asté, P.E. City of Fal lls Church Subject: CITY MS4 4 TRACKING G TOOL & Date: February 20 0, 2014 CHESAPE EAKE BAY P PROGRAM B BMP S Backgrou und The US E Environmenta al Protection Agency (EPA A) established d the Chesap peake Bay To otal Maximum m Daily Load (TM MDL) in 201 0 as a “pollu ution diet” w with accounta ability measu ures and initia atives establi ished to restore th he Chesapeak ke Bay. Th his “diet” re equires a 25% % reduction in nitrogen , 24% reduc ction in phosphoro ous, and 20% % reduction in sediment ove er the baselin ne load. To ad ddress this, th he Commonw wealth of Virginia d developed the e Phase 1 Wa atershed Imple ementation P Plan (WIP) in November o of 2010, and t the WIP Phase 2 in n March 2012 2, which outli ned how it w ould achieve these reducti ions. One of the plan com mponents that the s tate committ ed small Pha ase II MS4s t to was phase ed load reduc ctions from e existing land sources (retrofits) over three su uccessive five e (5) year perm mit cycles. T This numeric requirement was embodie ed in the Chesapeak ke Bay TMD DL Special Co ondition of the e small MS4 g general perm mit. As a sma ll MS4, the C City of Falls Church is no ow tasked wit th the challen nge of identif fying load red ductions from exis ting sources of at least 5% % over the 20 009 baseline year by 2015 5 in an Actio on Plan, with on-the- ground re eductions ach hieved by 20 18. At least t 40% of the total on-the- -ground load d reductions m must be achieved by 2023. W While Virginia a’s small MS4 4 general per rmit did not o outline detaile ed acceptable e means and meth hods to achi ieve the redu uctions, the Virginia De epartment of f Environmen ntal Quality (DEQ) subsequen ntly develope ed a draft guid dance docume ent that does. This docum ment is titled D DRAFT Guida ance for the Chesa apeake Bay TM MDL Action P Plan , and is in n its third ver rsion as a draf ft form. Acco ording to DE Q, as of late Febru uary 2014, th he guidance w was under inte ernal review and DEQ’s p plan “ is [to] f finalize in Ap pril and July ”. provide a series of outr reach meeting gs to MS4 per rmittees durin ng June and J The DEQ Q guidance i incorporates several of th he EPA Che esapeake Bay y Program O Office (CBPO O) final approved reports that t outline rec commendatio ns of how states can a account for load reducti ions by stakehold ers. The repo orts were deve eloped by sev veral Expert P Panels, organi ized by the C CBPO. Introduct tion Williamsb burg Environ nmental Grou up, Inc. (WE EG), now St tantec develo oped a MS4 Tracking To ool and Standard Operating Pr rocedures (SO OP) for City s staff, in coord dination with h the City of F Falls Church and the Chesapeak ke Bay Foun ndation. The e spreadsheet based tool in ncludes activ vities that are e listed in the e City’s MS4 Prog gram Plan. T The intent is that the tool and SOPs w will enable m more regular u updates of Ci ity MS4 related ac ctivities as th hey occur, wh hich will in t turn lead to m more accurat te record-kee eping, a more e robust program p plan execution n, and facilita ation of annua al report docu umentation. e 225 ● Richmo 3225 ● (804) 2 470 1011 1 Boulder Sprin ngs Drive Suite ond, Virginia 2 67-3474 ● FAX X (804) 267-34
F e bruary 2 20, 2014 MS4 T rac k king and Che e sape ake Bay y T MDL Page 2 o f 14 The tool a also includes multiple act tivities that ar re listed as V Virginia Depa artment of En nvironmental Quality (DEQ) an nd CBPO appr roved Best m management pr ractices (BMP Ps) that may contribute to the Chesapea ake Bay TMDL lo oad reduction s. The purpo ose of this m memo is to co oordinate and d match to the e extent poss sible the City of Fa alls Church a activities repo orted in the M MS4 Tracking g Tool with th he acceptable means and m methods and BMP s approved to o reduce load ds to understa and the potent tial for existi ing City activ vities to contr ribute to required r reductions. While the e DEQ Guida nce has not y yet been offic cially approve ed, it is the m most authorit tative and ap plicable reference document fo or the purpos ses of assessi ng acceptable e load reduct tion methods s for this mem mo. T o meet the required red ductions, Fall ls Church ca an implement t BMPs that are in the V Virginia Stor rmwater Clearingh house or have e been approv ved by the C Chesapeake B Bay Program Office. Dep pending on th he BMP selected, the following g methods ca an be used to estimate the e pollutant of f concern (PO OC) reduction ns to be credited: 1. E Efficiency BM MPs – To calcu ulate the cred dits generated d by structural l BMPs, Falls s Church may y use, as ap pplicable: a. the eff ficiencies in th he Virginia S tormwater Cl learinghouse; ; b. the ret trofit perform ance curves p provided by th he Bay Progr ram; or c. the app proved or inte erim Bay Pro gram efficien ncies. 2. L Land Use Cha ange BMPs – Load reducti ions will be c credited on a per acre basi is. These cre dits can be e calculated u using the conv version table (See Table 2) ). 3. U Urban Stream m Restoration – load redu uctions shoul ld be estima ated using ei ther the app propriate m methodology specified in the Chesapea ake Bay Pro ogram Expert t Panel guida ance or curre ent Bay Pr rogram interi m values. 4. V Virginia Nutri ient Credit T Trading Progr ram – Falls C Church may purchase cre edits from a nutrient cr redit bank app proved by DE EQ. 5. N Nutrient Mana agement – Nu utrient Manag gement can b be credited w when applied to unregulate ed land. F alls Church m may not rece eive credit fo or nutrient m management a applied to re gulate lands or golf co ourses. 6. O Other BMPs A Approved by t the Director o of DEQ. A full list t of the CBPO O BMP Repo orts is provid ed in Attach hment A . Th he status of ea ach is listed, as only four are a approved, but many are aw waiting approv val, in active d development, , or TBD. Th he following s sections highlight individual li ine item activ vities listed i in the City o of Falls Chur rch MS4 Tra acking Tool t that are potentially y relevant and d may allow t the City to rec ceive credit fo for Chesapeak ke Bay TMDL L reductions. e 225 ● Richmo 3225 ● (804) 2 470 1011 1 Boulder Sprin ngs Drive Suite ond, Virginia 2 67-3474 ● FAX X (804) 267-34
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