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Drainage Projects

Projects include: Green Stormwater Infrastructure, Thornton Creek Confluence, Pearl Street Project, and many more. Drainage and Creek Projects

LOWER TAYLOR CREEK RESTORATION PROJECT

Located near the south end of Lake Washington in southeast Seattle, Lower Taylor Creek flows through areas with poor habitat. The restoration project will help improve the stream channel and surrounding habitat, aid fish passage upstream, and reduce local flooding. Taylor Creek

BICYCLE SAFETY

Seattle Public Utilities (SPU) is working closely with the Seattle Department of Transportation (SDOT) to replace older storm drain covers in an effort to improve roadway conditions for bicycling throughout the City. Bicycle Safety

BROADVIEW PROJECTS

Seattle Public Utilities (SPU) is working in areas of the Broadview neighborhood to make improvements in the functioning of the sewer and drainage systems, as well as to improve water quality. SPU currently has three projects in the Broadview area focused on these issues, including two pilot projects to test some methods for meeting some of our goals for the neighborhood. Broadview Projects

THORNTON CREEK CONFLUENCE & MEADOWBROOK POND

The Thornton Creek Confluence project will help restore water quality, improve fish and wildlife habitat, reduce local flooding, and prepare for other flood reduction projects in the future. The creek is the largest watershed in Seattle, draining a 12-square-mile region of relatively dense biodiversity for an urban setting and home to over 200,000 people. The Meadowbrook Pond phase of the project was completed in 2013. Thornton Creek Confluence & Meadowbrook Pond

GREEN STORMWATER INFRASTRUCTURE

Guidance for Seattle’s urban landscape, creating green elements that welcome the rain – storing, draining, and cleaning it. Learn how stormwater flow and water quality code requirements can be achieved by using Green Stormwater Infrastructure. Green Stormwater Infrastructure

KNICKERBOCKER FLOODPLAIN

The Knickerbocker floodplain site is a section of the South Branch of Thornton Creek in Northeast Seattle. This project will relocate several hundred feet of the creek and create a 1.5 acre vegetated floodplain. This increased storage capacity will provide environmental benefits to downstream stream-side properties and improve the habitat for biological communities within the creek. A new pedestrian bridge over the creek will also be built. Knickerbocker Floodplain

MADISON VALLEY PROJECT

The Madison Valley Project was completed in 2013. The new infrastructure is capable of containing the amount of stormwater that caused flooding and numerous sewer backups in the two largest storms in 157 years of record – August 2004 and December 2006. Madison Valley Project

MAPES CREEK

The Lower Mapes Creek Restoration Project moves the creek from a storm drain into a parallel, dedicated pipe and then restores approximately 350 feet of the creek into an open, natural channel through Beer Sheva Park to Lake Washington. This project represents an opportunity to restore stream mouth habitat in an area heavily used by juvenile Chinook salmon. Mapes Creek

MIDVALE STORMWATER PROJECT

SPU constructed a stormwater holding area on a 1.8-acre commercial site in north Seattle that has a history of flooding during heavy rain storms. The project reduces the potential for localized flooding, and provides water quality treatment to reduce the amount of pollutants entering Lake Union. The Midvale Stormwater Project was completed in 2013. Midvale Stormwater Project

PEARL STREET PROJECT

Maple Elementary and several other properties in the Pearl Street area of West Beacon Hill have experienced recent sewer backups and flooding, a critical public health and safety issue. SPU is examining the scope of the problem and assessing feasible solutions to prevent future storm-related flooding and sewer backups into residences, businesses, and schools. Pearl Street Project

SEWAGE OVERFLOW PREVENTION

The City of Seattle has negotiated a first-of-its-kind proposed agreement that will prevent sewage overflows by allowing the city to use the most cost-effective and environmentally-beneficial projects to control and treat both stormwater and sewage. View the Long-term Control Plan that will guide the development of projects to be constructed over the next 15 years. Sewage Overflow Prevention

SWALE ON YALE

SPU is working with Cascade neighborhood businesses and property owners to construct a stormwater treatment system on four blocks of Yale Avenue North and Pontius Avenue North. This project will consist of four biofiltration swales, a pre-treatment swirl concentrator and a diversion structure. Swale on Yale

THORNTON CREEK WATER QUALITY CHANNEL

The Thornton Creek Water Quality Channel project was completed in 2009. The Thornton Creek Water Quality Channel project uses natural drainage system technology – drainage that mimics the way nature works - to clean the water, slow it down and let water flow through the channel year-round. The design includes native landscaping and pedestrian pathways that provide access throughout the site. Thornton Creek

SOUTH PARK PROJECTS

These sewer and drainage improvements will protect public health and safety by preventing sewer backups into people’s homes and businesses, as well as preventing street flooding. They will also help to protect the Duwamish Waterway from polluted stormwater runoff. Construction is expected in 2015. Funding is provided by drainage and wastewater rates. South Park Projects

NE 93rd STREET CULVERT REPAIR PROJECT

Seattle Public Utilities (SPU) will repair the culvert that carries Thornton Creek under NE 93rd Street to reduce the risk of sudden road failure during heavy rains. The culvert is at risk of failing, which would isolate several homes from access to Sand Point Way NE. NE 93rd Street Culvert Repair Project