Water Drop

Water Quality in the Arroyo Seco

Major progress is being made in cleaning up the water quality in the Arroyo Seco. This page summarizes recent developments and how you can contribute constructively to protecting the Arroyo Seco River.

Water Quality Monitoring

The Arroyo Seco Stream Team is a corps of dedicated volunteers who are working to improve the Arroyo by water quality monitoring, stream cleanups, habitat restoration and other projects. Each month volunteers collect samples at ten key spots in the Arroyo Seco watershed. The Stream Team also has other regular events for a variety of skills and interest, so this is a great way to get involved.

The Stream Team has been collecting water quality samples at key spots in the Arroyo Seco watershed for more than a year. Training is provided by the Arroyo Seco Foundation for people who want to participate in the water quality monitoring program. The training covers the types of pollutants found in the Arroyo Seco River and how to monitor their presence in order to develop a program to improve water quality. It's a rewarding way to contribute to improving the Arroyo.

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JPL/NASA Cleanup

The City of Pasadena and NASA/JPL have signed an agreement to build a treatment plant to clean up the water in the Hahamongna region of the Arroyo tainted by perchlorate. The agreement has taken six years to achieve but reflects substantial progress achieved in the last year to moving forward to clean up the source of the pollution and to treat the contaminated water.

JPL Cleanup Progress | Association of Ground Water Agencies Article

North East Trees Water Quality Study

Jason Pelletier of North East Trees has compiled a major water quality study of the Arroyo Seco Watershed. This project was funded by a water quality grant (Proposition 13) from the State of California. The Plan proposes projects and programs to improve water quality and restore habitat in the urbanized portions of the Arroyo Seco watershed, and builds on the joint work completed by North East Trees and the Arroyo Seco Foundation in the Arroyo Seco Watershed Restoration Feasibility Study, completed in 2002. The appendices provides analysis and background on water quality concerns and best management practices.

To download the plan, please click here: Water Quality Plan  |  Appendix

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Stop Global Warming

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Forging a Sustainable Watershed

How can we better manage local water resources to stretch our supplies and maximize efficiency? That's the goal of the Arroyo Seco Watershed Sustainability Program.

A Sustainable Arroyo