BLD20170007 - Stormwater Review - 1.pdf
Stormwater Review
Date of Review: February 7, 2017
th
File/Address: BLD20170007 / 8822 218 St SW
Reviewer: Robert C. Edwards, PE, Stormwater Engineer, City of Edmonds
Background
This is classified as a Category 2 Small Site because it proposes impervious area exceeding 5,000 SF.
Category 2 Small Site Projects are subject to Small Site Minimum Requirements 1, 2, 3, 4, 5, 6, 7, 8, 9,
10, and 11.
TheSupremeCourtofWashingtonissuedarulingonDecember29,2016regardingtheͻǝĻƭƷźƓŭͼ
ofStormwaterregulations.ThisrulingupholdstheDepartmentof9ĭƚƌƚŭǤƭregulationsfor
applicationandconstructiondatesforprojectswithStormwaterrequirements.
TheCityofEdmondshasendeavoredtoclarifytheimpactsoftherulingand9ĭƚƌƚŭǤƭ
regulationsonapplicationforsubdivisionsandshortsubdivisionssubmittedpriortoJanuary1,
2017.TheDepartmentofEcologyprovidedguidancetotheCityonJanuary30,2017,confirming
thatapplicationsforsubdivisionsandshortsubdivisionsacceptedbytheCityofEdmondspriorto
January1,2017shallconstituteanapplicationforthedefinitionoftheDepartmentof9ĭƚƌƚŭǤƭ
NPDESPhaseIIpermit.SuchprojectsthatdonotstartconstructionbyJanuary1,2022willbe
subjecttothenewDepartmentofEcologyregulations.
Consistentwith5h9ƭNovember2015clarificationontiming(postedontheirwebsite),thisshall
beinterpretedtomeanthatifasubdivisionapplicationisreceivedbytheCitypriortoJanuary1,
2017,thesubdivisionandsubsequentbuildingpermitsfortheindividuallotswillbeallowedto
completedesignandconstructionconsistentwiththestormwatermanagementcodeunder
whichtheirstormsystemwasdesigned.Ifthesubdivisionincludedrestrictionsorrequirements
fortheindividuallots,(e.g.maximumimpervioussurface,LID.atƭΜͲthoserequirementsshould
berecordedforeachlotandmustbeenforcedwhentheindividuallotisdeveloped.Again,such
projectsthatdonotstartconstructionbyJanuary1,2022willbesubjecttothenewDepartment
ofEcologyregulations.
ApplicantsarecautionedthattheDepartmentofEcologyhasnotissuedawrittendecisionin
supportofthisguidance.Forthisreason,thestormwatercommentsprovidedarepreliminary
andsubjecttorevisionshouldtheDepartmentofEcologyissueawrittendecisionthat
contradictstheguidanceinitiallyreceivedbytheCity.
Minimum Requirement #1 – Preparation of Stormwater Site Plan
Comments:
1.Sheet SP-01: Connection to the City’s MS4 allowed at structures only. Plan shows SD line teeing
into existing culvert.
2.Sheet SP-01: Show short plat property line between lots
Minimum Requirement #2 – Construction Stormwater Pollution Plan
Comments: None
Minimum Requirement #3 – Source Control of Pollution
Comments: None
Minimum Requirement #4 – Preservation of Natural Drainage Systems
Comments: None
Minimum Requirement #5 – Onsite Stormwater Management
Comments: N/A - detention
Minimum Requirement # 6 – Runoff Treatment
Comments: None
Minimum Requirement #7 – Flow Control
Comments:
1.Sheet DT-02: Minimum diameter for control structure is 54-inches
Minimum Requirement #8 – Wetland Protection
Comments: N/A
Minimum Requirement #9 – Operation and Maintenance
Comments: None
Minimum Requirement # 10 – Offsite Analysis and Mitigation
Comments: None
Minimum Requirement #11 – Financial Liability
Comments: None