1. Erosion Hazard Near Sensitive Waterbodies
No-Disturbance Area Pilot Program
SMC 21A
Planning Commission Meeting
October 5, 2017

2. Purpose
Review the content of the Erosion Hazards Near Sensitive Water Bodies Overlay No-Disturbance Area Pilot Program and proposed elimination of the program in anticipation of the October 19, 2017 Public Hearing.

3. Planning Commission’s Role Tonight
Review
Informational Only
Regular City Business (Limited Substantive)
Policy Input (In-Depth Substantive)

4. Process Planning Commission Review Planning Commission Sept Oct Oct 215
Oct 21
Background Information
Q & A
Work Session
Review & Comment
Public Hearing
Deliberation
Recommendation

5. Background
EHNSWB NDA
The ENHSWB NDA Pilot Program was added to the SMC as part of the ECA rules in 2013
The Pilot Program was not made effective until March of 2017
On May 16, 2017, the Council, citing concerns that the requirements and development regulations of the Pilot Program are inadequate to protect against potentially significant adverse impacts within the no-disturbance area, requested Staff prepare interim development regulations removing the Pilot Program from the SMC
May 22, 2017 the Council declared an emergency and adopted interim development regulations under ordinance O Seismic Hazard Areas
Interim regulations removed the Pilot Program from SMC 21A as an interim measure
Council directed staff to evaluate the components of the Pilot Program as previously found in SMC 21A and engage the Planning Commission in consideration of potential permanent changes

6. Chapter 21A.50 SMC Environmentally Critical Areas Geo-Science Areas
Critical aquifer Recharge Areas
Seismic Hazard Areas
Landslide Hazard areas
Erosion Hazard Areas
Erosion Hazard Near Sensitive Waterbodies Overlay

7. SMC 21A.15.415 Erosion Hazard Areas
Areas in the City underlain by soils that are subject to severe erosion when disturbed.
These soils include the following when they occur on slopes greater than 15%.
The Alderwood gravelly sandy loam (AgD)
The Alderwood and Kitsap soils (AkF)
The Beausite gravelly sandy loam (BeD and BeF)

8. SMC 21A.15.417 Erosion Hazard Near Sensitive Waterbodies Overlay
An area within the City where sloped areas posing erosion hazards, or contributing to erosion hazards, that drain directly to lakes or streams of high resource value.
The erosion hazard near sensitive water body overlay is divided into two areas:
No-Disturbance Area
Properties Draining to the No-Disturbance Area

9. SMC 21A.15.417 Erosion Hazard Near Sensitive Waterbodies Overlay
1. The No-Disturbance Area:
Established on the sloped portion of the special district overlay to prevent damage from erosion.
2. Properties Draining to the No-Disturbance Area:
Areas are within the erosion hazard near sensitive water body overlay that drain to the no-disturbance area.

10. SMC 21A.50.225 Erosion Hazard Near Sensitive Waterbodies Overlay
Purpose:
Is to provide a means to designate sloped areas posing erosion hazards that drain directly to lakes or streams of high resource value that are particularly sensitive to impacts of increase erosion and the resulting sediment loads from development

11. SMC 21A.50.225 Erosion Hazard Near Sensitive Waterbodies Overlay
Limitation on Development in the No-Disturbance Area:
Development shall not occur in the no-disturbance area, except for the development activities listed below and if they meet additional requirements.
Single-family residences
Utility corridors
Streets and utilities providing sole access to buildable property
Public parks
Work authorized pursuant to the pilot program

12. SMC 21A (5) - Pilot Program
Erosion Hazard Near Sensitive Waterbodies Overlay
Allowing subdivisions in limited circumstances
Established to allow pilot project subdivision, including clearing and development projects within the no-disturbance area on land that has slopes of less than 40 percent grade and that is located outside of environmentally critical area buffers.
Not authorized within the mapped Ebright Creek, Pine Lake Creek, Zackuse Creek, and “mid-Monohon” sub-basins.

13. SMC 21A (5) - Pilot Program
Erosion Hazard Near Sensitive Waterbodies Overlay
Purpose:
Is to allow for limited development within the no-disturbance area under strict limitations in order to evaluate the ability to allow increased development within the no-disturbance area without adversely affecting the water quality of Lake Sammamish.
Eligibility:
A maximum of four subdivision projects are authorized by this pilot program.

26. EHNSWB NDA Undeveloped Parcels
Sub-dividable Parcels
Study based on available information and is meant for policy level analysis

27. Analysis Pilot Program Requirements SMC 21A.225(5)
4 projects were allowed under the Pilot Program
2 of the subdivision projects require a tight-line drainage system (pipe conveying water to Lake Sammamish)
2 require strict application of Low Impact Development (LID) practices
All Pilot Program projects are subject to restrictive construction windows, clearing limits, and comprehensive monitoring requirements

28. Analysis Pilot Program Application
Cost of Pilot Program subdivision development is high
Limited to larger subdivisions to absorb the cost
Counter-intuitive to the intent of the EHNSWB, PDNDA, and NDA
Larger projects are more prone to causing erosion impacts

29. Analysis Pilot Program Application Conclusion:
Large scale subdivision within the NDA is not appropriate and presents a high level of erosion risk and is contrary to the intent of the EHNSWB overlay and NDA rules.

30. Sammamish Municipal Code
Erosion Hazard Near Sensitive Waterbodies Overlay
Recommendation:
Permanently remove Pilot Program from SMC 21A

31. Next Steps DATE ACTION Oct 5
Planning Commission Work Session – Erosion Hazards Near Sensitive Waterbodies Overlay No-Disturbance Area Code
Oct 19
Planning Commission Public Hearing and Recommendation
Nov 6
City Council Public Hearing and First Reading of the Ordinance
Nov 7
Nov 21
City Council Second Reading of the Ordinance