Water Quality - Sediment collected
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Sediment collected
Sediment is loose particles of sand, clay, silt and other substances produced by erosion and decomposing material. It can be deposited in, transported by or suspended in water. Sediment that reaches a body of water can decrease water clarity, prevent sunlight from reaching aquatic plants, smother fish spawning areas and cause a variety of other problems.
Performance analysis
FY2023
WSDOT prevents sediment from reaching water bodies
During FY2023, WSDOT collected 1,306 cubic yards of sediment. Of this sediment, 1,239 cubic yards came from catch basins and stormwater facilities, while 67 cubic yards came from ferry terminals. This was 442 cubic yards (25.3%) less than the 1,748 cubic yards removed in FY2022.
Many variables affect the amount of sediment removed each year, such as the weather and the amount of sand used to provide traction on icy roads, the number of stormwater facilities in need of maintenance, and available funding. Once removed, sediment is considered solid waste and WSDOT disposes of it accordingly.
FY2022
WSDOT prevents sediment from reaching water bodies
During FY2022, WSDOT collected 1,748 cubic yards of sediment. Of this sediment, 1,682 cubic yards came from catch basins and stormwater facilities, while 66 cubic yards came from ferry terminals. This was 2,203 cubic yards (55.8%) less than the 3,951 cubic yards removed in FY2021.
Many variables affect the amount of sediment removed each year, such as the weather and the amount of sand used to provide traction on icy roads, the number of stormwater facilities in need of maintenance, and available funding. Once removed, sediment is considered solid waste and WSDOT disposes of it accordingly.
FY2021
WSDOT prevents more than 3,900 cubic yards of sediment from reaching water bodies
During FY2021, WSDOT collected 3,951 cubic yards of sediment. Of this sediment, 3,883 cubic yards came from catch basins and stormwater facilities, while 68 cubic yards came from ferry terminals. This was 1,008 cubic yards (34.25%) more than the 2,943 cubic yards removed in FY2020.
Many variables affect the amount of sediment removed each year, such as the weather and the amount of sand used to provide traction on icy roads, the number of stormwater facilities in need of maintenance, and available funding. Once removed, sediment is considered a solid waste and WSDOT disposes of it accordingly. WSDOT employs various operational best management practices—such as street sweeping and regularly cleaning debris from stormwater catch basins—to prevent sediment from entering stormwater runoff and discharging to lakes, streams and other water bodies.
FY2020
WSDOT prevents more than 2,800 cubic yards of sediment from reaching water bodies
During FY2020, WSDOT collected 2,943 cubic yards sediment. Of this sediment, 2,851 cubic yards came from catch basins and stormwater facilities while 92 cubic yards came from ferry terminals. This was 40 cubic yards (1.34%) less than the 2,983 cubic yards removed in FY2019.
Many variables impact the amount of sediment removed each year, such as the weather and the amount of sand used for icy roads, the number of stormwater facilities in need of maintenance, and available funding. Once removed, sediment is considered a solid waste and WSDOT disposes of it accordingly. WSDOT employs various operational best management practices—such as street sweeping and regularly cleaning debris from stormwater catch basins—to prevent sediment from entering stormwater runoff and discharging to lakes, streams and other water bodies.
FY2019
WSDOT prevents more than 2,900 cubic yards of sediment from reaching water bodies
During FY2019, WSDOT collected 2,983 cubic yards of sediment, the equivalent of more than 3,300 bathtubs. Of this sediment, 2,914 cubic yards came from catch basins and stormwater facilities while 69 cubic yards came from ferry terminals. This was 860 cubic yards (22.4%) less than the 3,843 cubic yards removed in FY2018.
Many variables impact the amount of sediment removed each year, such as the weather and sanding needs for icy roads, the number of stormwater facilities in need of maintenance and available funding. Once removed, sediment is considered a solid waste and WSDOT disposes of it accordingly. WSDOT employs various operational best management practices—such as street sweeping and regularly cleaning debris from stormwater catch basins—to prevent sediment from entering stormwater runoff and discharging to lakes, streams and other water bodies.
Ecology reissues WSDOT's municipal stormwater permit
The Department of Ecology reissued WSDOT's municipal stormwater permit in spring 2019. The new permit added the City of Shelton, the City of College Place, and Clallam County's unincorporated urban growth area to the places in which WSDOT must implement the permit requirements.
It also added new areas that require watershed cleanup plans (known as Total Maximum Daily Loads). These watersheds include Clarks Creek, the North Fork Palouse River, the Deschutes River, Percival Creek, and Budd Inlet tributaries system.
The permit requires WSDOT to develop a Stormwater Management Program Plan describing how the agency will implement the permit requirements. The plan documents the procedures and practices used to reduce the discharge of pollutants from storm sewer systems owned or operated by the agency. While the agency implements some pollution prevention activities statewide, the plan specifically applies to areas covered by the permit. WSDOT is required to submit an updated stormwater plan to Ecology by October 31 each year.