CIP-01: Stream Channel Stabilization, Silver Creek

Transcription

1 CIP-01 CIP-01: Stream Channel Stabilization, Silver Creek HIGHEST PRIORITY This project consists of stream channel stabilization to address channel incision and the replacement of two cross-culverts. Preferred Solution: Implement stream restoration techniques using log weirs and constructed woody debris matrices with minimal rock placement to reduce velocities and trap sediment and replace two cross-culverts for a total project length of 350 linear feet (LF). Coordinate project planning and implementation with CIP-02, CIP-03, and CIP-06 in the same creek system. Coordinate especially with CIP- 02, which consists of similar strategy in a downstream reach. This project is related to CIP-02, CIP-03, and CIP-06 (same creek system); problems addressed by this project: HS-01, HS-02, HS-03, HS-06, HS-07, HS-08, HS-09. Prevention of additional channel incision (down-cutting) Reduction in erosion and subsequent deposition of channel bed material Reduction in solids loading to lake creek channel with rocks and logs culvert Minimize or eliminate channel incision and related erosion Ensure health and safety by managing drainage conveyance Maintain aesthetically pleasing appearance of area Permitting, Regulatory, or Other Issues: Access to private property. Permits for in-water work including USACE Section 404 permit, WDFW HPA and environmental review, seasonal clearing restrictions $440,000 Schedule for Implementation: Within 6-year planning window

2 CIP-02 CIP-02: Main Channel Velocity Reductions, Silver Creek HIGHEST PRIORITY The purpose of this project is to reduce velocities in Silver Creek and to promote settling and retention transported to this location. Preferred Solution: Implement natural stream restoration techniques using log weirs and constructed woody debris matrices to reduce velocities and trap sediment along 350-foot length, using pre-treatment in first few pools ; coordinate project planning and implementation with CIP-01, CIP-03, and CIP-06, as they are connected hydraulically. Coordinate especially with CIP-01, which consists of similar strategy in an upstream reach. This project is related to and downstream from CIP-01, CIP-03, and CIP-06 (same creek system); problems addressed (or partially addressed) by this project: HS-01, HS- 02, HS-03, HS-06, HS-07, HS-08, HS-09. Reduction of erosive stormwater velocities Reduction in pollutant (including phosphorous) loading to Lake Whatcom through gravity settling and plant uptake creek channel with rocks and logs culvert Lessen stormwater velocities and capture solids transported from upstream reaches Ensure health and safety by managing drainage conveyance Maintain aesthetically pleasing appearance of area Permitting, Regulatory, or Other Issues: Access to private property, permits for in-water work, seasonal clearing restrictions $150,000 Schedule for Implementation: Within 6-year planning window

3 CIP-03 CIP-03: Upstream Channel Velocity and Volume Reduction, Silver Creek HIGHEST PRIORITY This project consists of altering 900 LF of side ditch (at approximately 4% slope) along Toad Lake Road. Preferred Solution: Implement natural drainage alternative of amended soils, vegetation, and cascade effect of step-pools to promote infiltration, biofiltration, and settling of sediment due to gravity within pre-treatment cells; perform programmatic alternatives concurrently to promote on-site retention, appropriate construction practices, hobby farm BMPs, tree cover retention, etc.; coordinate project planning and implementation with CIP-01, CIP-02, and CIP-06 (same creek system). This project is related to CIP-01, CIP-02, and CIP-06 (same creek system); problems addressed (or partially addressed) by this project: HS-01, HS-02, HS-03, HS-06, HS-07, HS-08, HS-09. Minimization of erosive stormwater velocities and attenuate peak flows Volume reduction through infiltration Reduction in pollutant loading to Lake Whatcom through gravity settling and plant uptake water dirt concrete check dam Prevent erosion within the ditch Maximize stormwater runoff velocity reduction Ensure health and safety by managing drainage conveyance Maintain aesthetically pleasing appearance of area limitations, permits for in-water work, seasonal clearing restrictions $230,000 Schedule for Implementation: Within 6-year planning window

4 CIP-04 CIP-04: Natural Drainage Retrofits, Hillsdale Sub-basin HIGHEST PRIORITY Retrofit the existing informal drainage system of ditch and culvert with wide s with a more natural drainage system. Approximately 800 LF of way would be altered for this pilot project. Preferred Solution: Implement natural drainage alternative as 1-block pilot project (approximately 800 LF), including bioswales with amended soils and vegetation and width reduction; perform programmatic alternatives concurrently to promote stormwater controls on private property (tree cover retention, on-site retention and dispersion, etc.); Lahti Drive by D Linda Street is a feasible site for this project. Problems addressed (or partially addressed) by this project: HS-04, HS-05. raingarden driveway Volume reduction through infiltration Minimization of erosive stormwater velocities by mimicking natural drainage patterns Reduction in pollutant loading to Lake Whatcom through gravity settling and plant uptake Promote stormwater runoff volume reduction limitations; requires significant public involvement and consensus; coordinate with bus route locations; seasonal clearing restrictions $410,000 Schedule for Implementation: Within 6-year planning window

5 CIP-05 CIP-05: Velocity Reductions, Toad Lake Road at Academy Street HIGHEST PRIORITY This project will reduce the erosive velocities in the ditches along Todd Lake Road. Preferred Solution: Implement natural drainage alternative of amended soils, vegetation, and cascade effect of step-pools to promote infiltration, biofiltration, plant uptake, and settling of sediment due to gravity in first few cells as pre-treatment ; perform programmatic alternatives concurrently to promote on-site retention in new development, appropriate construction practices, tree cover retention Problems addressed (or partially addressed) by this project: AC-02, AC-03, AC-04. Lessen erosive stormwater velocities Capture of solids from upstream reaches via settling Volume reduction through infiltration Pollutant loading reduction to Lake Whatcom through gravity settling and plant uptake water dirt concrete check dam Minimize erosion of ditch and capture solids transported from upstream limitations; seasonal clearing restrictions $200,000 Schedule for Implementation: Within 6-year planning window

6 CIP-06 CIP-06: Culvert Replacement, Silver Creek (Hillsdale/ Brownsville) HIGHEST PRIORITY Replace the 100-foot long, 24-inch-diameter culvert that conveys one branch of Silver Creek across and under Brownsville Drive, then across Hillsdale Road with a larger culvert. Preferred Solution: Quantify effects of other projects planned for Silver Creek using modeling or other means, then re-determine need for upsized culvert; coordinate project planning and implementation with CIP-01, CIP-02, and CIP-03, as they are connected hydraulically. This project is related to CIP-01, CIP-02, and CIP-03 (same creek system); problems addressed (or partially addressed) by this project: HS-01, HS-02, HS-03, HS-06, HS-07, HS-08, HS-09). This project is on the Whatcom County 6-year CIP list ( ) as priority #29. Increase in drainage conveyance capacity Decrease in risk of localized drainage issues Ensure health and safety by increasing drainage conveyance Quantify effects of culvert upsizing on downstream streambank erosion culvert limitations; traffic disruptions; seasonal clearing restrictions; may promote erosion downstream because would eliminate the bottleneck that may currently limit velocities conveyed Estimated Costs: $260,000 Schedule for Implementation: This project is currently on the Whatcom County 6-year CIP list ( ). According to that list, preliminary engineering is to take place on this project in year 1 (2007) and construction in years 4-6 ( ).

7 CIP-07 CIP-07: Velocity and Volume Reductions, Fremont Street near Coronado Avenue HIGH PRIORITY The purpose of this project is to reduce velocities and volumes of runoff in this Fremont Street side ditch by altering approximately 700 LF of ditch length at a slope of less than 5%. Preferred Solution: Implement natural drainage alternative of amended soils, vegetation, and cascade effect of step-pools to promote infiltration, biofiltration, plant uptake, and settling of sediment due to gravity; perform programmatic alternatives concurrently to promote on-site retention in new development, appropriate construction practices, tree cover retention, etc.; coordinate project planning and implementation with CIP-08 and CIP-09, as they are connected hydraulically. This project is related to CIP-08, CIP-09 and CIP-14 (same creek system); problems addressed (or partially addressed) by this project: SR-01, SR-02, SR-03, SR-04. Reduction of erosive stormwater velocities Volume reduction through infiltration Reduction of pollutant loading to lake through gravity settling and plant uptake water dirt concrete check dam Minimize erosion of ditch Reduce runoff volume and velocities limitations; permits for in-water work, traffic disruptions; seasonal clearing restrictions $210,000 Schedule for Implementation: Within or beyond 6-year planning window

8 CIP-08 CIP-08: Velocity and Volume Reductions, Coronado Avenue HIGH PRIORITY The purpose of this project is to reduce velocities and volumes of runoff along Coronado Avenue, and consists of altering approximately 600 LF of drainage course. Preferred Solution: Implement natural drainage alternative of amended soils, vegetation, and cascade effect of step-pools to promote infiltration, biofiltration, plant uptake, and settling of sediment due to gravity using the first few cells as pre-treatment ; perform programmatic alternatives concurrently to promote on-site retention in new development, appropriate construction practices, tree cover retention, etc.; coordinate project planning and implementation with CIP-07 and CIP-09, as they discharge in the same area. This project is related to CIP-07, CIP-09 and CIP-14 (same creek system); problems addressed (or partially addressed) by this project: SR-01, SR-02, SR-03, SR-04. Reduction of erosive stormwater velocities Volume reduction through infiltration Pollutant loading reduction to Lake Whatcom through gravity settling and plant uptake water dirt concrete check dam Minimize stormwater velocities and volumes limitations; traffic disruptions; seasonal clearing restrictions; project would require removing flow from pipe and onto surface $290,000 Schedule for Implementation: Within or beyond 6-year planning window

9 CIP-09 CIP-09: Natural Drainage Retrofits, Strawberry Sub-basin HIGH PRIORITY The purpose of this pilot project is to reduce velocities and volumes of runoff in this unnamed creek system by reducing volumes and peak flows from approximately 600 LF of Lewis Avenue. Preferred Solution: Implement natural drainage alternative as 1-block pilot project on 600 LF of Lewis Avenue, including bioswales with amended soils and vegetation and width reduction; perform programmatic alternatives concurrently to promote stormwater controls on private property (tree cover retention, on-site retention and dispersion, cisterns, rain barrels, dry wells, etc.). This project is related to CIP-07, CIP-08 and CIP-14 (same creek system); problems addressed (or partially addressed) by this project: SR-01, SR-02, SR-03, SR-04. raingarden driveway Volume reduction through infiltration Erosive stormwater velocity reduction Reduction in pollutant loading to Lake Whatcom through gravity settling and plant uptake Promote stormwater runoff volume and velocity reduction limitations; requires significant public involvement and buy-off; seasonal clearing restrictions $150,000 Schedule for Implementation: Within or beyond 6-year planning window

10 CIP-10 CIP-10: Natural Drainage Retrofits, Geneva Sub-basin, Cedar Hills Avenue and Ridgewood Avenue HIGH PRIORITY This project consists of a pilot project altering 1 block (approximately 500 LF) of residential area using on-site stormwater controls and natural drainage system strategies. Preferred Solution: Implement hybrid pilot project option of on-site drainage system and natural drainage system for 1 residential block (500 LF), including bioswales with amended soils and vegetation and width reduction; possible cost-share with residents to implement rain gardens and other on-site stormwater controls as vital part of this project; perform programmatic alternatives concurrently to promote stormwater controls on private property (tree cover retention, on-site retention and dispersion, cisterns, rain barrels, dry wells). Problems addressed (or partially addressed) by this project: GN-05. Volume reduction through infiltration Minimization of erosive stormwater velocities Promote stormwater runoff volume reduction Reduce current level of reactive drainage-related maintenance performed by Whatcom County Public Works M&O raingarden driveway limitations; requires significant public involvement and buy-off; seasonal clearing restrictions; high water table should be considered in design, use of rain gardens important $230,000 Schedule for Implementation: Within or beyond 6-year planning window 10

11 CIP-11 CIP-11: Velocity Reductions, Northshore Drive at Agate Bay Lane HIGH PRIORITY Stabilize and improve the 400-foot-long ditch along Agate Bay Lane above Northshore Drive. Preferred Solution: Implement natural drainage alternative of amended soils, vegetation, and cascade effect of step-pools to promote infiltration, biofiltration, plant uptake, and settling of sediment due to gravity; utilize first few cells as pre-treatment to capture solids; perform programmatic alternatives concurrently to promote on-site retention, hobby farm BMPs, tree cover retention. Problems addressed (or partially addressed) by this project: AG-07. Reduction of erosive stormwater velocities Volume reduction through infiltration Reduction in pollutant loading to Lake Whatcom through gravity settling and plant uptake water dirt concrete check dam Minimize erosion of ditch limitations; county is well-traveled at relatively high speeds; seasonal clearing restrictions $140,000 Schedule for Implementation: Within or beyond 6-year planning window 11

12 CIP-12 CIP-12: Water Quality Protection, Agate Heights Estates HIGH PRIORITY This project retrofits portion of an existing drainage system that serves Agate Heights Estates, an existing development which consists of already-constructed homes as well as several homes currently under construction. This project is intended to be applied concurrently with programmatic solutions, including inspection and enforcement during construction and education. Preferred Solution: Implement end-of-pipe treatment of media filtration using proprietary technology (such as StormFilter or equivalent), with emphasis on solids removal from runoff stream. The media filter can be sited to the west of the existing stormwater pond in order to treat runoff from steep s. Implement high-flow bypass ; implement concurrently with programmatic solutions of increased inspection and enforcement during construction, education, regulatory. Problems addressed (or partially addressed) by this project: AG-04. culvert pond stormwater treatment Reduction of erosive stormwater velocities Volume reduction through infiltration Reduction in pollutant loading to Lake Whatcom through gravity settling and media filtration Remove sediments transported via stormwater before reaching Lake Whatcom limitations; steep slopes in some areas; seasonal clearing restrictions $200,000 Schedule for Implementation: Within or beyond 6-year planning window 12

13 CIP-13 CIP-13: Stream Buffer Restoration, Beaver Creek LOW PRIORITY This project consists of restoring the riparian corridor for Beaver Creek in order to decrease water temperature, increase water quality, and improve physical habitat complexity for fish. Preferred Solution: Implement riparian corridor restoration by planting trees and other vegetation to promote a 1000-LF natural riparian corridor along portions of Beaver Creek through Sudden Valley. Problems addressed (or partially addressed) by this project: AU-05. Improvement in water quality, reduction in temperatures for fish Increase in channel complexity for fish Improve habitat for fish Permitting, Regulatory, or Other Issues: Stream reach is on private property (Sudden Valley Corporation), seasonal clearing restrictions Estimated Costs: Not developed due to schedule for implementation Schedule for Implementation: Beyond 6-year planning window, reassess need for project before implementation 13

14 CIP-14 CIP-14: Culvert Replacement, Lake Whatcom Boulevard at Coronado LOW PRIORITY Increase the size of the culvert crossing Lake Whatcom Boulevard near Coronado Avenue. Preferred Solution: Quantify effects of other projects planned for this unnamed creek using modeling or other means, then redetermine need for upsized culvert; coordinate project planning and implementation with CIP-07, CIP-08, and CIP-09 (same creek system). This project is related to CIP-07, CIP-08, and CIP-09 (same creek system); problems addressed (or partially addressed) by this project: SR-01, SR-02, SR-03, SR-04. Lake Whatcom culvert Increased drainage conveyance capacity Decreased risk of localized drainage issues Ensure health and safety by increasing drainage conveyance limitations; traffic disruptions on both Lake Whatcom Boulevard and Coronado Avenue; seasonal clearing restrictions Estimated Costs: Not developed due to schedule for implementation Schedule for Implementation: Beyond 6-year planning window, reassess need for project before implementation 14

15 CIP-15 CIP-15: Culvert Replacement, Lake Whatcom Boulevard at Castle Avenue LOW PRIORITY Increase the size of the culvert crossing Lake Whatcom Boulevard near Castle Avenue. Preferred Solution: Remove existing culvert and install 50 linear feet of a larger-sized cross-culvert. Problems addressed (or partially addressed) by this project: SR-08. culvert Lake Whatcom Increased drainage conveyance capacity Decreased risk of localized drainage issues Reduced maintenance requirements of the system by increasing capacity Ensure health and safety by increasing drainage conveyance limitations; traffic disruptions; seasonal clearing restrictions Estimated Costs: Not developed due to schedule for implementation Schedule for Implementation: Beyond 6-year planning window, reassess need for project before implementation 15

16 CIP-16 CIP-16: Culvert Replacement, Lake Whatcom Boulevard near Sudden Valley LOW PRIORITY Replace the 400-foot cross-culvert under Lake Whatcom Boulevard in the vicinity of Sudden Valley (near Harbor View Court North, within Sudden Valley) with a larger size. Coordinate with Sudden Valley. Problems addressed (or partially addressed) by this project: SV-01. Increase in drainage conveyance capacity Decrease of risk of localized drainage issues Reduced maintenance requirements of the system by increasing capacity Lake Whatcom culvert Ensure health and safety by increasing drainage conveyance limitations; traffic disruptions; seasonal clearing restrictions Estimated Costs: Not developed due to schedule for implementation Schedule for Implementation: Beyond 6-year planning window, reassess need for project before implementation 16

17 CIP-17 CIP-17: Fish Passage Improvements, Austin Creek LOW PRIORITY Replace existing culvert with fish-friendly culvert where Austin Creek enters Beaver Creek after crossing Lake Louise Boulevard near the Sudden Valley maintenance facility to remove fish barrier. Problems addressed (or partially addressed) by this project: AU-07. dirt culvert Expanded fish passage opportunities for fish Improve fish passage for fish Permitting, Regulatory, or Other Issues: Spawning season restrictions for construction, permits for in-stream work, seasonal clearing restrictions. Estimated Costs: Not developed due to schedule for implementation Schedule for Implementation: Beyond 6-year planning window, reassess need for project before implementation 17

18 CIP-18 CIP-18: Drainage Improvements, Northshore Drive at East North Street LOW PRIORITY This project is intended to address this localized drainage issue. Preferred Solution: Implement natural drainage alternative of bioswales lined with amended soils, vegetation, and cascade effects (when necessary, due to slope constraints) along 750 foot length of East North Street, while maintaining drainage conveyance ; coordinate with programmatic solutions. Problems addressed (or partially addressed) by this project: AC-01. Increased drainage conveyance capacity Decreased risk of localized drainage issues Minimized maintenance requirements of system because of increased capacity water dirt concrete check dam Permitting, Regulatory, or Other Issues: Project would require coordination with City of Bellingham, project site is within City of Bellingham; physical space limitations; seasonal clearing restrictions Estimated Costs: Not developed due to schedule for implementation Schedule for Implementation: Beyond 6-year planning window, reassess need for project before implementation 18

19 CIP-19 CIP-19: Drainage and Water Quality Improvements, Lowell Avenue and Cedarbrook Court LOW PRIORITY This project is intended to alleviate these localized drainage issues while at the same time increasing water quality of runoff reaching Oriental Creek. Preferred Solution: Treatment Train alternative of both end of pipe media filtration and natural drainage alternative, with natural drainage methods used along nearly 1,500 LF of side. Problems addressed (or partially addressed) by this project: BL 01. swale stormwater treatment Increased drainage conveyance capacity and/or promote infiltration Decreased risk of localized drainage issues Reduced pollutant loading to Lake Whatcom through gravity settling and media filtration Reduction in maintenance requirements Reduce stormwater runoff volumes and peak flows Remove pollutants transported via stormwater Reduce current level of reactive drainage-related maintenance limitations; seasonal clearing restrictions Estimated Costs: Not developed due to schedule for implementation Schedule for Implementation: Beyond 6-year planning window, reassess need for project before implementation 19

20 CIP-20 CIP-20: Drainage Improvements, Glen Cove Lane LOW PRIORITY This project will mitigate localized drainage issues is the area around Glen Cove Lane in the Geneva Sub-basin. Preferred Solution: Promote on-site residential stormwater management using rain gardens, rain barrels, and cisterns, along with education on and/or assistance with on-site drainage practices appropriate for the soil and drainage conditions in the area. (Problems addressed (or partially addressed) by this project: GN-03) driveway raingarden Decrease in localized drainage issues Reduce stormwater runoff volumes and peak flows Reduce current level of reactive drainage-related maintenance limitations; public acceptance Estimated Costs: Not developed due to schedule for implementation Schedule for Implementation: Beyond 6-year planning window, reassess need for project before implementation 20