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Cedar Mill News
Volume 5, Issue 9


September 2007

The Powers that Be
Clean Water Services

Clean Water Services is the sanitary sewer and surface water management utility for nearly 500,000 customers in urban Washington County and small portions of Multnomah County, Clackamas County, Lake Oswego, and Portland. Clean Water Services operates four wastewater treatment plants, constructs and maintains flood management and water quality projects and manages flow in the Tualatin River to improve water quality and protect fish habitat. Although Clean Water Services maintains a close working relationship with Washington County government, it is a separately managed and financed public utility.

Clean Water Services’ Design & Construction Standards require developers to protect water resources as they build our communities through aggressive erosion prevention and sediment control programs, construction of water quality facilities, and protection and enhancement of vegetated corridors for water quality sensitive areas.

How does Clean Water Services protect the water quality of the streams in the Cedar Mill area from the impacts of development?

Cedar Mill includes the steep headwater areas of Cedar Mill, Johnson, and Golf Creeks and their tributaries. The District’s program for protecting Water Quality Sensitive Areas like these requires that development set aside and enhance Vegetated Corridors (also known as “buffers”) along these streams and other water quality sensitive areas like wetlands. The width of the vegetated corridor varies based on the type of sensitive area and the slope of the surrounding area. At a minimum, a 25-foot wide vegetated corridor in good condition is required along streams, but in steeper terrain, buffer widths can increase up to 200 feet.

In addition, Clean Water Services requires developers to build water quality treatment facilities—most commonly swales---that will treat the stormwater runoff from the impervious surfaces like streets, sidewalks, and rooftops.

Does Clean Water Services allow developers to put streams into culverts or fill wetlands to increase buildable area for new housing and commercial development?

Streams and wetlands are regulated by the Department of State Lands (DSL) and US Army Corps of Engineers (COE). Although we work closely with the two agencies, Clean Water Services does not directly regulate streams and wetlands; our rules focus on the vegetated corridors next to these resources. The COE and DSL review and issue various permits to alter water quality sensitive areas after they have completed extensive review; this review includes an analysis of the resource and alternatives. If DSL or COE allow an impact to the resource, they generally require mitigation for the impact.

Who is responsible for maintaining water quality facilities once they are built?

For the first two years after construction, the developer is responsible for ensuring that the plants in the facility are healthy and that the facility is functioning. Clean Water Services’ inspection staff regularly visits newly constructed facilities to make sure the necessary work is performed. After the first two years, maintenance on almost all of the facilities built for residential development is done by Clean Water Services. Some older facilities are maintained by Homeowners Associations (HOA). District staff is available and frequently responds to requests from HOA or their landscape maintenance contractors to provide advice and guidance about proper maintenance practices to ensure that the facilities continue to function well.

What do builders have to do to protect streams from construction runoff? What happens if there are erosion problems on a construction site?

Clean Water Services was one of the first jurisdictions in the state to implement an erosion prevention and sediment control program for construction activities that disturb 500 square feet or more of area. In addition, construction sites larger than 1 acre also require a permit from the Oregon Department of Environmental Quality.

Erosion control on active construction sites can be challenging, especially during wet weather. Clean Water Services regularly inspects active construction sites to ensure compliance, and during the winter months, inspections are made more frequently. We also will respond with an inspector if citizens see and report a potential problem to us. If a problem is found, the District uses a combination of education and increasingly severe enforcement tools to bring a site back into compliance. These tools range from deficiency notices to Stop Work Orders to Civil Citations with fines up to $1000 per day per violation.

Instead of treating stormwater once it runs off a site, wouldn’t using Low Impact Development to reduce the amount of stormwater from a site be a better option?

Low Impact Development (LID) is another approach to managing stormwater runoff. It has advantages and challenges, and so using it on every single development may not be appropriate.

The purpose of Low Impact Development is to reduce the impact that development has on natural resources including creeks, streams, and wetlands. As it applies to stormwater, developments using Low Impact Development Approaches (LIDA) use different building techniques or materials to reduce the amount of stormwater that is generated from a site. The most common methods for reducing the amount of stormwater include reducing the amount of total impervious surface, using infiltration systems, and occasionally by retaining rainwater and re-using it for irrigation or other beneficial uses.

Within Washington County, there is growing interest in using LIDA on new developments. However, these techniques are still relatively new and untested here. Developers, design engineers, and local governments do not have a lot of direct experience implementing low impact development or know how it would work over time. In addition, since many of the techniques are focused at the source – meaning individual homeowners have to be responsible for maintaining them forever – education and good designs are critical. Our soil types make designing infiltration systems a bit more challenging; we don’t want to have standing water around people’s houses; and we don’t want to surprise future homeowners about their responsibilities.

How is Clean Water Services promoting Low Impact Development?

Clean Water Services, along with the cities in Washington County and the County itself are taking an active role in providing design opportunities and education for engineers, permit reviewers, site inspectors, contractors, and maintenance crews. The 2007 update of the Design & Construction Standards now includes a list of low impact development techniques that will be allowed. Staff is currently working on several proposed pilot projects (although none currently in the Cedar Mill area), advising developers on how they might use LID techniques, and assisting with informational guidelines that will encourage them.

What about existing, older developments? What is being done to treat stormwater runoff from those sites?

The regulations to treat stormwater with onsite water quality facilities have been in effect since 1992. District staff and developers are seeking opportunities to retrofit areas developed before then. The District’s rules also require treatment for any site that redevelops, even if no additional impervious surface is being added.

During the fiscal year 2007-2008, Clean Water Services will be embarking on a master planning effort to identify potential retrofit sites. We have also been working in conjunction with the cities and County to retrofit several stormwater outfalls throughout the county to provide water quality treatment.

How can Cedar Mill residents provide input on Clean Water Services’ rules, projects and policies?

All stakeholders including Cedar Mill residents are encouraged to participate in the District’s decision-making via public open houses, neighborhood project meetings, stakeholder dialogues, Clean Water Advisory Commission and Board of Director meetings, and by contacting staff when they have a suggestion or concern.



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Publisher/Editor:Virginia Bruce
12110 NW West Rd
Portland, OR 97229