General Grading and Drainage Requirements
For projects vested prior to September 30, 2010:
Permit application submittals can be scheduled online or by calling (425) 388-3311, ext. 2790.
What stormwater management forms do I need?
Restrictions related to Critical Areas:
- Critical Areas: Channel Migration Zone Maps (SCC 30.62B.330)
- Southwest UGA: Little Bear Creek Watershed (SCC 30.63C.025)
- Serene Way: Frontage improvement standards
- Lake Stevens UGA: Tightline systems are required (SCC 30.63A.225)
- Lake Stevens UGA: Detention facility design requirements - Weiser Creek, Burri Creek and Fox Creek basins (SCC 30.63A.226)
Outside Agency Requirements (applicant's responsibility):
All Developments: All new development must use adequate temporary erosion control Best Management Practices (BMP’s). If developing in a floodplain contact the Flood Hazard Specialist at 425-388-3311 extension 2731. If your development will occur within 300 feet of a FWHCA fish bearing stream, demonstrate compliance with SCC 30.62A.320(1)(c) and Rule 6225: Chapter 30.62A SCC Infiltration Standards.
Engineering Design and Development Standards (EDDS)
Drainage Regulations 30.63A
Grading Regulations 30.63B
Critical Area Regulations 30.62A, 30.62B, and 30.62C
Channel Migration Zones
Full Drainage Plan: Major Development proposals (more than 5,000 sq. ft. of new impervious surface area, or more than 5,000 cubic yards of gross cut or fill) generally require storm water detention and water quality treatment facilities designed by a professional engineer licensed in Washington.
Construction/Full Drainage Plan Checklist
Drainage Facility Maintenance Covenant (DFMC) – subdivisions
Drainage Facility Maintenance Covenant (DFMC) – other
Drainage Facility Maintenance Covenant Submittal Checklist
Record Drawings (as-built) Checklist
Rule 3044 - Standards for Stormwater Pollution Prevention Plans
2005 Dept. of Ecology Stormwater Management Manual, Vol. II
Drainage Information Summary Form
Targeted Drainage Plan: Other Developments (more than 200 but less than 5,000 sq. ft. of new impervious surface area) generally have no detention or water quality treatment requirements. A Targeted Drainage Plan can either be for construction, or can be a conceptual plan usually associated with a land use action going to hearing.
Targeted Drainage Plan Checklist
Grading Plan: A grading permit is required for all grading that does not meet the exemption requirements of 30.63B. When no impervious surfaces are proposed but a grading permit is still required, use the Grading Plan Submittal Checklist.
Grading Permits, Bulletin #35
Low Impact Development (LID) is now available for projects meeting LID Ordinance 30.63C, and is offered as an alternative. Use the 2005 DOE Manual if claiming credits in your detention pond sizing for using LID techniques.
Low Impact Development Manual
Request for Low Impact Development (LID) Pre-Application Meeting
Stormwater Management Manual for Western Washington (revised 2005)
Low Impact Development Stormwater Management Techniques, Bulletin #22
Low Impact Development Supplemental
Low Impact Development Modification from Snohomish County Code (SCC)
Low Impact Development Deviation from Engineering Design and Development Standards (EDDS)
Stormwater Facility & Low Impact Development System Maintenance Covenant
Assignment of Funds in Lieu of LID Paving Bond
Low Impact Development Paving Bond
Other Information Links:
Drainage Information for Home Builders
Drainage Needs Report and Maps
Engineering and Design Standards Deviation Request (EDDS)
Erosion Control for the Home Builder
Grading and Slope Information for Home Builders
Public Drainage Easement - Applicant's Submittal Checklist
Waiver and Modification Request
Wash. State Dept. of Transportation Highway Runoff Manual
Wash. State Dept of Transportation Hydraulics Manual
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