Oswego Lake Watershed Council

The Oswego Lake Watershed Council (OLWC) is a locally organized, non-profit, non-regulatory watershed stewardship organization established to improve the condition and health of the Oswego Lake watershed and its stream network.


Oswego Lake Watershed Council’s number one priority is the health of our community and volunteers. We appreciate all of you and want you to know that our staff is closely monitoring the spread of COVID-19 and taking appropriate measures to ensure that we are doing our part to promote wellness in the community. Until further notice, all public events, including volunteer events, have been canceled or postponed.

We are continuing to engage with the OLWC community online by using email and our social media platforms. As always, if you have any questions or concerns, please do not hesitate to reach out to us. We appreciate your patience and hope that all of you continue to stay healthy during this challenging time.

Take care,
OLWC Staff and Board

Black Lives Matter

Black Lives Matter

The murders of George Floyd and Breonna Taylor at the hands of the police have reinvigorated national conversations around racial justice, and police violence against Black people. We condemn this racial violence. 



Soil Your Undies!

Have you ever had the urge to bury a brand-new pair of 100% cotton underwear under (at least) 6 inches of soil, wait 60 days, and then dig them back up to see what happened? Now may be your chance! Oswego Lake Watershed Council (OLWC) is encouraging our community to get dirty and participate in the nationwide Soil Your Undies challenge!

View the recorded Weed Watchers Workshop and to take the companion Workshop Quiz. Everyone who fills out a quiz will be entered in a drawing for a gift certificate to a Washington County nursery as well as gain access to a folder with additional resources to help you manage invasive species on your property.

But wait – there’s more!  Click on the links below to register for these free up-coming workshops:

Oswego Lake Tree Summit

Let’s Branch Out and
Talk Trees Together!

The Tree Summit is in partnership with the Oswego Lake Watershed Council, the Lake Oswego Sustainability Network, the Mountain Park Homeowners’ Association, and 14 neighborhood associations.


Tansy Ragwort

Weed of the Month: Tansy Ragwort

Tansy ragwort (Senecio jacobaea) is an invasive weed with a long and deadly history in the Pacific Northwest. In Oregon, it is designated as a Class B invasive weed.

This noxious weed is dangerous to humans and livestock if ingested.


2020 Local Native Plant Sales

Find local sources of native plants, including local plant sales, as well as retail, wholesale and native plant seed suppliers. 

Summer is NOT the time to plant, of course, but this can help you plan for Fall.

For more resources including what plants to use for different conditions (sunny & dry, shady & wet, etc.), click here.


Resources for Residents

Be a part of the solution. There are many ways to help protect watershed health at home.

The links on this page provide useful information to help you improve water quality and wildlife habitat in your yard and your community.