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


2020 Lake Oswego Tree Summit

Our Precious Urban Forest:
Discovering, Understanding, Enhancing in a Time of Climate Change

As stewards of our urban forest in Lake Oswego, you are invited to attend and participate in this community-led event to celebrate trees, Saturday, November 21, 2020, from 10:00 AM to 12 Noon. This is the second annual Tree Summit and there will be a review of accomplishments from last year. It will be a Zoom meeting, and registration is required.

The Tree Summit is in partnership with the Oswego Lake Watershed Council and the Lake Oswego Sustainability Network.

A Lake Oswego home in our "urban forest"

Come to this Tree Summit to enhance your arboreal knowledge and discover ways to connect with and enhance the ecological health of our urban forest.

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! #SoilYourUndies

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.


Himalayan Blackberry

Weed of the Month: Spurge Laurel

Spurge laurel (Daphne laureola) is neither a spurge nor a laurel, but rather an invasive plant in the Daphne family. This perennial plant has poisonous berries, spreads aggressively in our native forests, and is increasingly being found in Clackamas County.

Introduced in Oregon as an evergreen landscape plant, this invasive weed quickly naturalized and escaped into woodlands around the state.


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.


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. 

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