AgBoardNPDES presentation11 13 07

Stormwater Management Regulation Update: 

Snohomish County Planning & Development Services Stormwater Management Regulation Update UDC Update Project Agricultural Advisory Board November 13, 2007

UDC Life, Health & Safety Pillar: 

UDC Life, Health & Safety Pillar

Why Are We Doing This Update?: 

Why Are We Doing This Update? Protect health and safety Prevent/minimize degradation of water quality and slope instability Preserve WQ for aquatic habitats, recreation, and drinking water Comply with CWA and DOE NPDES Permit

Phase 1 Municipal Stormwater Permit Requirements: 

Phase 1 Municipal Stormwater Permit Requirements Adopt Appendix 1 Minimum Technical Requirements for New Development and Redevelopment Adopt 2005 DOE Stormwater Manual for Western Washington with a Snohomish County Addendum

Project Managers: 

Project Managers

How is Stormwater Managed?: 

How is Stormwater Managed? Construction Stormwater Pollution Prevention Plan (SWPPP) Control water flow, install sediment controls, stabilize soils, protect slopes, wetlands, drain inlets, channels and outlets Control pollutants with Best Management Practices (BMPs), source control, runoff treatment, and treatment facility sizing

What’s New?: 

What’s New? More restrictive exemptions Applies to development and redevelopment Applies to Class IV FP conversions - stormwater calculations required More analysis is required for discharges to wetlands and a different baseline is used for the analysis in the 2005 DOE Manual

What’s New? (continued): 

What’s New? (continued) Larger detention and retention ponds Pre LDA site inspection Reporting and inspections: existing facilities and upgrades New pollution source control rules Permit has several less restrictive provisions than existing code

Code Revisions: 

Code Revisions Revisions to drainage & grading codes - Exemptions - Development & redevelopment thresholds - Minimum requirements

DOE 2005 Manual: 

DOE 2005 Manual Adopt 2005 DOE Manual with addendum and ref to drainage and grading Change to reflect Snohomish County business practices Modify for clarity Change to make “user friendly”

Engineering Design & Development Standards (EDDS): 

Engineering Design & Development Standards (EDDS) Revisions to address LID design standards Review other standards (roads, drainage, etc.) for appropriate revisions Modify for consistency with code and Drainage Manual Adopted per rulemaking process

Permit Exemptions: 

Permit Exemptions 30.63A.020  Exemptions. (draft code in progress)    (1)  The following commercial agricultural production activities conducted outside ((critical)) wetlands, lakes, marine waters, and fish and wildlife habitat conservation areas and on land designated riverway commercial farmland, upland commercial farmland, or local commercial farmland by the comprehensive plan are exempt from the requirements of this chapter:      (a)  Tilling, soil preparation, and maintenance; and      (b)  Fallow rotation, planting, and harvesting except: (i) Conversions from timberland to agriculture and (ii) Construction of impervious surfaces, including but not limited to roads.   

Permit Exemptions: 

Permit Exemptions    (2)  The following commercial agricultural production activities conducted outside ((critical)) wetlands, lakes, marine waters and fish and wildlife habitat conservation areas and on land designated riverway commercial farmland, upland commercial farmland, or local commercial farmland by the comprehensive plan are exempt from all other requirements of this title except that they shall comply with the stormwater pollution prevention plan (SWPPP) requirements of SCC 30.63A.220(1)(a)-(g), and:      

Permit Exemptions: 

Permit Exemptions (a)  Maintenance and repair except the creation of any new impervious surface on private property of existing commercial agricultural facilities, which may include drainage facilities, ponds, animal stock flood sanctuaries, animal waste management facilities, agricultural buildings, fences, roads, and bridges;      (b)  New construction (((including enlargement))) of drainage ditches that are less than 500 cubic yards or less of land disturbing activity of 2,000 square feet or less, which does not adversely impact ((critical areas, lakes,)) wetlands, lakes, marine waters and fish and wildlife habitat conservation areas or upstream or downstream properties, when such ditches do not have a surface connection within 100 feet of wetlands, lakes, marine waters and fish and wildlife habitat conservation areas or which contain water on-site for retention, infiltration or evaporation pursuant to chapter 30.62 SCC.

Right to Farm (RTF): 

Right to Farm (RTF) DOE and FEMA exemptions: De minimus ag activities that do not alter contours including tilling, plowing, harvesting, soil amendments and farm ditch digging if the originally constructed ditch configuration is not altered & spoils are removed or tilled as a soil amendment. Exempt activities also include farm road construction or maintenance which does not alter contours, use culverts and is < 6 inches above grade.

Permit vs. RTF: 

Permit vs. RTF Federal CWA mandate trumps local initiative Not allowed: Construction of Roads Impervious Surfaces

County’s Strategy: 

County’s Strategy Discuss de-minimus RTF activity with DOE Provide de-minimus RTF justifications Send draft code to DOE including existing right to farm provisions

Right to Farm Justification: 

Right to Farm Justification DOE allows de minimus construction that does not alter contours Water infiltrates into outwash soils Roads typically generate < 0.1 cfs threshold DOE regulates stormwater on farmlands Drainage plans and development reg by NRCS Farm plans address stormwater management Farm roads typically do not impact stormwater systems

Alternatives: 

Alternatives Amend code to match permit and include options if DOE will not allow RTF Porous pavement on roads Quarry spalls access roads

Related Non-Exemptions: 

Related Non-Exemptions Conversion from timberland to agriculture not exempt

Agricultural Advisory Board Input: 

Agricultural Advisory Board Input Your comments and suggestions on RTF justification and options

General Project Schedule: 

General Project Schedule SEP: Draft codes and DOE Manual OCT – DEC: Draft documents and public outreach DEC: Review drafts FEB: Transmit codes and manual to DOE for 60-day review APR – JUL 2008: PC and Council Public Hearings AUG/SEP 2008: Adoption for NPDES permit compliance

Keep in Touch : 

Keep in Touch Status updates and drafts available on the UDC Update Project homepage at www.snoco.org (search UDC Update) Public can submit comments on the project page

Staff Contacts: 

Staff Contacts Bill Leif, Environmental Program Compliance Specialist, 425-388-3148 Randy Sleight, Chief Engineering Officer, 425-388-3311, x2014 Arthur Lee, Project Specialist, 425-388-3812 Bob McEwen, Transportation Specialist, 425-388-3488, x4578 Linda Kuller, Chief Planning Officer, 425-388-3412

Acronyms: 

Acronyms BMP – Best Management Practices CESCL – Certified Erosion-Soil Control Lead CWA – Clean Water Act DOE – Department of Ecology DOE Manual – 2005 Stormwater Manual for Western WA EDDS – Engineering Design & Development Standards LID – Low Impact Development NPDES – National Pollutant Discharge Elimination Permit SWPPP – Stormwater Pollution Prevention Plan WWHM: Western WA Hydrology Model