2013
CITY OF REDMOND, WASHINGTON
CITYWIDE WATERSHED MANAGEMENT PLAN
Prepared for
City of Redmond
Public Works Natural Resources Division
Prepared by
Herrera Environmental Consultants, Inc.
Note:
Some pages in this document have been purposely skipped or blank pages inserted so that this
document will copy correctly when duplexed.
2013
CITY OF REDMOND, WASHINGTON
CITYWIDE WATERSHED MANAGEMENT PLAN
Prepared for
City of Redmond
Public Works Natural Resources Division
Andy Rheaume, Senior Watershed Planner
15670 NE 85th Street
Redmond, Washington 98052
Prepared by
Herrera Environmental Consultants, Inc.
2200 Sixth Avenue, Suite 1100
Seattle, Washington 98121
Telephone: 206/441-9080
November 25, 2013
jr 10-04884-000 2013 city of redmond watershed mgt plan
CONTENTS
Acknowledgments …………………………………………………………………………….. vii
City of Redmond………………………………………………………………………….. vii
Elected Officials …………………………………………………………………… vii
Project Team ……………………………………………………………………… vii
Washington State Department of Ecology ……………………………………………….. vii
Herrera Environmental Consultants ……………………………………………………… vii
List of Abbreviations and Acronyms …………………………………………………………… ix
Executive Summary ………………………………………………………………………….. xiii
Chapter 1
Introduction ………………………………………………………………………. 1
1.1
Goals and Objectives ………………………………………………………………. 3
1.2
Geographic Scope ………………………………………………………………….. 4
1.3
Document Organization ……………………………………………………………. 4
Chapter 2
Regulatory Drivers ……………………………………………………………….. 7
2.1
Growth Management Act …………………………………………………………… 7
2.2
Shoreline Management Act ………………………………………………………… 8
2.3
Clean Water Act ……………………………………………………………………. 9
2.4
NPDES ……………………………………………………………………………… 11
2.5
WRIA 8 Salmon Recovery Plan and Endangered Species Act ……………………… 12
2.6
Groundwater Regulations …………………………………………………………. 13
2.7
Muckleshoot Indian Tribe Treaty Rights …………………………………………… 14
Chapter 3
Watershed Conditions …………………………………………………………… 15
3.1
Climate ……………………………………………………………………………. 15
3.2
Topography and Soils ……………………………………………………………… 17
3.3
Existing Land Use and Land Cover ………………………………………………… 18
3.4
Groundwater ………………………………………………………………………. 18
3.5
Surface Waters of the City ………………………………………………………… 29
3.5.1
Class I Waterbodies ………………………………………………………. 30
3.5.1.1
Sammamish River ……………………………………………. 35
3.5.1.2
Bear Creek …………………………………………………… 35
3.5.1.3
Evans Creek ………………………………………………….. 36
3.5.1.4
Lake Sammamish …………………………………………….. 45
3.5.2
Class II Waterbodies ……………………………………………………… 45
3.5.2.1
Clise Creek …………………………………………………… 46
3.5.2.2
Colin Creek ………………………………………………….. 55
3.5.2.3
Country Creek ……………………………………………….. 56
3.5.2.4
High School Creek ……………………………………………. 63
3.5.2.5
Idylwood Creek ………………………………………………. 64
3.5.2.6
Mackey Creek ………………………………………………… 69
3.5.2.7
Monticello Creek …………………………………………….. 70
jr 10-04884-000 2013 city of redmond watershed mgt plan
3.5.2.8
Perrigo Creek ………………………………………………… 70
3.5.2.9
Peters Creek …………………………………………………. 75
3.5.2.10
Sears Creek ………………………………………………….. 76
3.5.2.11
Seidel Creek …………………………………………………. 83
3.5.2.12
Tosh Creek …………………………………………………… 83
3.5.2.13
Tyler’s Creek ………………………………………………… 84
3.5.2.14
Valley Estates Creek …………………………………………. 89
3.5.2.15
Villa Marina Creek …………………………………………… 90
3.5.2.16
Willows Creek ……………………………………………….. 97
Chapter 4
Watershed Planning Approach …………………………………………………. 101
4.1
Watershed Management Strategy Prioritization …………………………………. 102
4.1.1
Prioritization Based on Puget Sound Characterization ………………….. 102
4.1.2
Refined Prioritization by the City of Redmond …………………………. 104
4.2
Application of Prioritization ……………………………………………………… 110
4.2.1
GMA Comprehensive Plan ……………………………………………….. 110
4.2.1.1
Land Use Planning ………………………………………….. 110
4.2.1.2
Capital Facilities Planning ………………………………….. 112
4.2.1.3
Transportation Planning ……………………………………. 112
4.2.1.4
Shoreline Master Program ………………………………….. 118
4.2.2
Clean Water Act …………………………………………………………. 119
4.2.3
NPDES ……………………………………………………………………. 123
4.2.4
Flow Control …………………………………………………………….. 124
4.2.4.1
Method ……………………………………………………… 124
4.2.4.2
Tracking and Reporting …………………………………….. 126
4.2.5
Runoff Treatment ……………………………………………………….. 127
4.2.5.1
Method ……………………………………………………… 127
4.2.5.2
Tracking and Reporting …………………………………….. 129
4.2.6
Low Impact Development (LID) …………………………………………. 129
4.2.6.1
Method ……………………………………………………… 129
4.2.6.2
Tracking and Reporting …………………………………….. 130
4.2.7
WRIA 8 Salmon Recovery Plan …………………………………………… 131
Chapter 5
Watershed Needs Assessment and Rehabilitation Strategies ………………….. 135
5.1
Watershed Needs Assessment ……………………………………………………. 135
5.1.1
Science Review ………………………………………………………….. 136
5.1.2
Stream Functions Model …………………………………………………. 136
5.2
Rehabilitation Tools ……………………………………………………………… 138
5.3
Watershed Rehabilitation Strategies …………………………………………….. 138
5.3.1
Protection Watersheds ………………………………………………….. 143
5.3.1.1
Colin Creek …………………………………………………. 143
5.3.1.2
Mackey Creek ……………………………………………….. 144
5.3.1.3
Seidel Creek ………………………………………………… 147
5.3.2
Highest Restoration Watersheds ………………………………………… 147
5.3.2.1
Bear Creek ………………………………………………….. 147
5.3.2.2
Clise Creek ………………………………………………….. 153
5.3.2.3
Evans Creek …………………………………………………. 154
iii
jr 10-04884-000 2013 city of redmond watershed mgt plan
5.3.2.4
High School Creek …………………………………………… 164
5.3.2.5
Monticello Creek ……………………………………………. 167
5.3.2.6
Tosh Creek ………………………………………………….. 178
5.3.3
Restoration Watersheds …………………………………………………. 184
5.3.3.1
Sammamish River …………………………………………… 184
5.3.3.2
Perrigo Creek ……………………………………………….. 188
5.3.3.3
Peters Creek ………………………………………………… 193
5.3.3.4
Tylers Creek ………………………………………………… 193
5.3.3.5
Willows Creek ………………………………………………. 194
5.3.4
Restoration Development Watersheds ………………………………….. 195
Chapter 6
Implementation Strategy ………………………………………………………. 197
6.1
BMP Selection Guidance ………………………………………………………….. 197
6.2
Climate Change Adaptation ………………………………………………………. 198
6.2.1
Predicted Climate Effects ……………………………………………….. 198
6.3
Funding Strategy …………………………………………………………………. 201
6.4
Effectiveness Monitoring Plan ……………………………………………………. 202
6.5
Adaptive Management Strategy ………………………………………………….. 203
Chapter 7
References ……………………………………………………………………… 205
Appendix A
Letters of Support from Washington State Department of Ecology
Appendix B
Modifications to Default NPDES Permit Requirements
Appendix C
Table Summarizing Multiple Benefits from Green Infrastructure BMPs
Appendix D
Effectiveness Monitoring Plan
jr 10-04884-000 2013 city of redmond watershed mgt plan
TABLES
Table 2.1
Chinook Habitat Watershed Evaluations for Redmond Area Class I
Streams. ……………………………………………………………………….. 13
Table 3.1.
Summary of Existing Watershed, Fish Use, and Water Quality Conditions
for Class I Waterbodies. ……………………………………………………….. 33
Table 3.2.
Summary of Existing Watershed, Fish Use, and Water Quality Conditions
for Class II Streams. ……………………………………………………………. 49
Table 4.1.
Management Strategies for Watersheds in the City of Redmond. ……………. 109
Table 4.2.
Projection of Parcels Likely to Develop or Redevelop by 2030 in the City
of Redmond. …………………………………………………………………… 111
Table 5.1.
Watershed and Stream Rehabilitation Tools. …………………………………. 139
Table 5.2.
Bear Creek Watershed Rehabilitation Strategies. …………………………….. 151
Table 5.3.
Clise Creek Watershed Rehabilitation Strategies. ……………………………. 157
Table 5.4.
Evans Creek Watershed Rehabilitation Strategies. …………………………… 161
Table 5.5.
High School Creek Watershed Rehabilitation Strategies. …………………….. 169
Table 5.6.
Monticello Creek Watershed Rehabilitation Strategies. ……………………… 173
Table 5.7.
Tosh Creek Watershed Rehabilitation Strategies. ……………………………. 181
Table 5.8.
Sammamish River Watershed Rehabilitation Strategies. ……………………… 189
Table 6.2.
Summary of Budgeted Capital Investments for the 2013-2018 Stormwater
CIP. ……………………………………………………………………………. 202
jr 10-04884-000 2013 city of redmond watershed mgt plan
FIGURES
Figure 1.1.
Vicinity and Watershed Map for the City of Redmond………………………….. 5
Figure 3.1.
Ambient Air Temperatures in the City of Redmond. ………………………….. 16
Figure 3.2.
Monthly Average Precipitation Totals for the City of Redmond from
1988-2008. ……………………………………………………………………… 17
Figure 3.3.
Topography in the City of Redmond. ………………………………………….. 19
Figure 3.4.
Geologic Cross-section of the City of Redmond and the Sammamish River
Valley. ………………………………………………………………………….. 21
Figure 3.5.
Soil Types in the City of Redmond. ……………………………………………. 23
Figure 3.6.
Distribution of Existing Land Use within the City of Redmond. ……………….. 25
Figure 3.7.
Distribution of Existing Land Cover within the City of Redmond. …………….. 27
Figure 3.8.
Wellhead Protection Zones in the City of Redmond. ………………………….. 31
Figure 3.9.
Drainage Areas for Class I Streams in the City of Redmond. ………………….. 37
Figure 3.10. Existing Watershed Conditions for the Sammamish River. …………………….. 39
Figure 3.11. Existing Watershed Conditions for Bear Creek. ……………………………….. 41
Figure 3.12. Existing Watershed Conditions for Evans Creek. ………………………………. 43
Figure 3.13. Existing Watershed Conditions for Lake Sammamish. …………………………. 47
Figure 3.14. Drainage Areas for Class II Streams in the City of Redmond. …………………. 53
Figure 3.15. Existing Watershed Conditions for Clise Creek. ……………………………….. 57
Figure 3.16. Existing Watershed Conditions for Colin Creek. ……………………………….. 59
Figure 3.17. Existing Watershed Conditions for Country Creek. ……………………………. 61
Figure 3.18. Existing Watershed Conditions for High School Creek. ………………………… 65
Figure 3.19. Existing Watershed Conditions for Idylwood Creek. …………………………… 67
Figure 3.20. Existing Watershed Conditions for Mackey Creek. …………………………….. 71
Figure 3.21. Existing Watershed Conditions for Monticello Creek. …………………………. 73
Figure 3.22. Existing Watershed Conditions for Perrigo Creek. …………………………….. 77
Figure 3.23. Existing Watershed Conditions for Peters Creek. ……………………………… 79
Figure 3.24. Existing Watershed Conditions for Sears Creek. ………………………………. 81
Figure 3.25.…