TagDes Moines Creek(169)

A fisheries biologist assessed the Port of Seattle's plan to use City of Seattle drinking water to boost summer flows in Miller and Des Moines Creeks when levels drop below 1.0 cubic feet per second. The report concludes that chlorine and fluoride in drinking water are toxic to fish and other aquatic life at very low concentrations, and that mixing drinking water into these small streams would far exceed Washington State water quality standards even with dilution. The biologist recommended against the plan and suggested that treated well water from within the local watersheds might be a less harmful alternative.

Letter dated August 18, 2000 from Keith R. Smith, Water Resources Manager at Port Of Seattle (Seattle-Tacoma International Airport), to Jillian Hoyt of Seattle Public Utilities, regarding the Des Moines Creek Basin Plan Flow Augmentation Facility. The Port seeks to purchase water from SPU as an alternate supply for the proposed flow augmentation facility, which

In July 2000, the Port of Seattle submitted an Implementation Plan to the Washington Department of Ecology outlining a proposed Des Moines Creek Flow Augmentation Facility near Seattle-Tacoma International Airport. The plan describes using water from a Port-owned well — currently used for golf course irrigation — to boost creek streamflow to at least one cubic foot per second and lower water temperatures to 16°C during summer low-flow periods. An automated monitoring station downstream would control pump operations, with a backup option to draw from the Port's municipal water distribution system if well water became unavailable.

In July 2000, the Port of Seattle submitted an Implementation Plan to the Washington Department of Ecology outlining a proposed flow augmentation facility for Des Moines Creek, located near Seattle-Tacoma International Airport. The plan described using water from a Port-owned well to increase stream flow to one cubic foot per second and reduce water temperatures to 16 degrees Celsius during summer low-flow periods, with the goal of improving water quality and aquatic habitat. The facility would involve reconfigured well pumps, an 800-foot pipeline, a stilling basin, and an automated monitoring station to regulate flow and temperature in the creek.

In June 2000, the Port of Seattle submitted a formal application to the Washington Department of Ecology to add a new use to an existing groundwater right for a well located on Port property near Seattle-Tacoma International Airport. The well, originally drilled in the late 1940s and previously used to irrigate the Tyee Valley Golf Course, was proposed to also provide flow augmentation and temperature control for Des Moines Creek as part of a jointly funded basin restoration plan. The application addressed the well's ownership history, its continuous use for golf course irrigation since the mid-1960s, and the Port's agreement with Highline Water District confirming the Port's title to the associated water right (Certificate No. 2369).

The Port of Seattle filed an Application for Change/Transfer of Water Right with the Washington State Department of Ecology in June 2000, seeking to add flow augmentation for Des Moines Creek as a purpose of use to an existing well water right (No. 2369) originally used for domestic supply, golf course irrigation, and related uses at Tyee Valley Golf Course in SeaTac. The proposed change would extend the water right beyond 2000 to support creek flow augmentation alongside continued domestic supply and golf course irrigation, covering the Des Moines Creek corridor from the airport property to the creek's mouth at Puget Sound. This application reflects the Port's efforts to manage water resources in connection with environmental and operational responsibilities related to Sea-Tac Airport.

A draft memorandum dated April 2000 summarizes range-finding water-effect ratio (WER) toxicity tests conducted for the Port of Seattle to measure copper levels in streams receiving stormwater runoff from Seattle-Tacoma International Airport (STIA). Water samples were collected from five sites — including Miller Creek and Des Moines Creek — during a storm event on April 15, 2000, and tested using Daphnia magna organisms to compare copper toxicity in site water versus clean laboratory water. The results were intended to determine whether more expensive definitive WER studies would be warranted, and to help establish site-specific water quality standards for copper.

This April 2000 draft memorandum from the Port of Seattle summarizes range-finding toxicity tests conducted to evaluate water-effect ratios (WERs) for copper in streams receiving stormwater runoff from Seattle-Tacoma International Airport (STIA). Water samples were collected from five sites—including Miller Creek and Des Moines Creek—during a storm event on April 15, 2000, and tested using Daphnia magna to measure how site water chemistry affects copper toxicity compared to clean laboratory water. The results were intended to help determine whether full definitive WER studies were warranted, which could support the establishment of site-specific water quality standards for copper in receiving streams.

Handwritten notes from a BEATAC meeting at the Port on April 20, 2000, AR018447, involving City of Des Moines personnel including Tom Walsh, Tacie Borden, John Marchiloro, Jim Kelly, and others. Topics include: stormwater review at FCC starting 5-5-00; SR-509 temporary interchange issues (ESA/BA review, Jonathan Freedman indirect impacts, erosion/sediment control, no federal nexus); LWS#3

Draft memorandum dated April 20, 2000, authored by Doug Henderson and Linda Logan (job number 556-2912-001) for Port of Seattle project files, summarizing range-finding water-effect ratio (WER) toxicity tests for copper in streams receiving Seattle-Tacoma International Airport (STIA) stormwater. Tests used Daphnia magna as indicator species; copper was spiked into site water and synthetic laboratory