Neighborhood & HOA Resources

Deciding the best way to care for land along streams and wetlands can be a challenge, but groups of homeowners and neighbors working together can make a positive impact on our watershed. 

An aerial view of Tigard homes with Mt. Hood in the background. The homes are lined up and have curated natural areas around them.

Each neighborhood and Homeowners Association (HOA) is different and represents a unique opportunity to engage a group of people to help protect our waterways. Explore the FAQs below and share this printable HOA Fact Sheet (PDF) with your homeowner group. If you don’t find what you’re looking for, please contact us.


How do HOAs find out what areas they are responsible for maintaining?

Land tracts owned by an HOA are shown on the subdivision plat map filed with the County, which also describes the HOA’s maintenance responsibilities. The HOA’s governance documents should include the plat map. To get a copy of a plat map, contact the Washington County Surveyor’s office at 503.846.8723.

Are neighborhoods and HOAs responsible for maintaining wetlands and streams?

Yes, many HOAs own creeks and wetlands that they must maintain as described in the recorded plat. It’s important to maintain wetlands and creeks with healthy native plants to remove pollution from runoff and protect our community’s water quality. A list of landscaping contractors experienced in this type of work is included. Read the Streamside Care Guide (PDF) to find out more about what you can do to enhance and protect stream and wetland areas.

How can neighborhoods and HOAs control invasive weeds like blackberry and ivy?

The most effective control is ongoing removal of Himalayan blackberry, English ivy, and other invasive plant species, and replanting with native plants. Learn more:

Can neighborhoods and HOAs remove trees along streams or other areas?

With approval from Clean Water Services, the HOA may remove trees from tracts near wetlands and streams. For information, please contact our permit counter at 503.681.5100.

What assistance can a group of homeowners get from Clean Water Services?

In some cases, Clean Water Services staff or our partners at Tualatin Soil and Water Conservation District can provide technical assistance and native plants to help HOAs maintain healthy creeks and wetlands. Call us at 503.681.3600 for more information.

You can also reserve the Watershed Wagon (PDF), filled with tools and supplies for community events like invasive removal and native planting in the Tualatin River Watershed. The Wagon has equipped community groups at nearly 50 enhancement sites since 2001.

If you are constructing drainage infrastructure improvements for a group of properties, you can also apply for a stormwater local improvement district (PDF) to receive CWS assistance.

Who maintains water quality facilities?

Some water quality facilities are public, and some are private. If you are not sure whether a water quality facility is public or private, call our main line, 503.681.3600. There are some private facilities that may be the responsibility of landowners to maintain. Learn more about the Private Water Quality Facility Management Program. Facilities that are considered “public” are maintained by Clean Water Services or partner cities. If there is overgrown vegetation in a water quality facility, Clean Water Services may remove some of the vegetation. Please call Field Operations to report this issue at 503.547.8100.

I noticed that there is an easement to Clean Water Services over the tract that the HOA maintains. What does this easement mean?

The easement restricts development but allows the property owner (often the HOA) to maintain invasive species and enhance the native vegetation in the area. Clean Water Services may have an easement over wetlands, streams, and adjacent vegetated corridors for storm and surface water drainage and to preserve water quality.



An easement is an interest in land which entitles the owner of the interest, the grantee, to use or enjoy the land of another, the grantor. It does not grant the right to possess the land but gives the grantee the ability to use all or a portion of the land as specified in the easement.


A surveyed map of a town, section, or subdivision indicating the exact locations and boundaries of individual properties, streets, easements, and public recreation areas. Plats are usually required for government approval of subdivisions and are usually publicly recorded documents.


One or more contiguous lots or parcels in the same ownership.