NORTH BEND – In an effort to protect the environment and comply with new laws protecting the Puget Sound water system, the city of North Bend has developed its first comprehensive stormwater management plan.

The plan was designed to address drainage and flooding problems within city limits, improve water quality and lessen the environmental impacts of untreated stormwater runoff into the Snoqualmie River, which ultimately flows into Puget Sound. North Bend is one of several cities to develop such a plan.

Currently, most of the city’s existing drainage system consists of open channels, ditches along roads and streets and storm sewer pipes, or culverts, that are too small for an increasing amount of water-runoff volume.

“The storm drains throughout the city are undersized and this just contributes to the flooding problems,” said Sara Barry, North Bend special projects coordinator. “We really don’t have adequate treatment right now for the stormwater before it discharges to the river, and this contributes to pollution in Puget Sound.”

She added that the worst areas are the downtown business district and the Silver Creek neighborhood, where storm drains are too small for water runoff.

North Bend has always experienced flooding, primarily because of its proximity to the Snoqualmie River and its tributary creeks and streams. The flatness of the city’s topography and amount of rainfall – estimated to be 60 to 70 inches per year – contribute to the flooding.

On top of that, the city has experienced tremendous growth – 84 percent since 1990, according to the 2000 Census. North Bend now has approximately 4,746 residents, compared with 2,578 in 1990, and many of those residents live in new homes.

New homes and businesses have added impervious surfaces and changed water-runoff patterns, which also contribute to flooding. When land is cleared for development and roads and parking lots have been paved, runoff on impervious surfaces occurs faster than on porous soil.

The plan was developed with city funding, along with contributions from the state Department of Ecology through its Centennial Clear Water Fund and Water Pollution Control Revolving Fund. To create the plan, the city enlisted a citizen advisory committee that has met for the past year to come up with solutions to drainage problems. Several studies were also conducted by various engineering firms to determine problem flooding and drainage areas. Other cities’ stormwater systems and utility bills were also examined.

The plan has five components that together would help flooding and water quality problems. They include: regulatory recommendations issued by the state concerning the city’s stormwater maintenance; capital improvements; a maintenance and operation program; public education and management of the plan; and lastly, financing.

For the regulatory component, adoption of a stormwater maintenance program was mandated by the Puget Sound Water Quality Management Act in 1994 and the Puget Sound Water Quality Protection Act, established in 1996. The acts require local jurisdictions to adopt stormwater management ordinances with minimum standards for new development and redevelopment.

Capital improvements would be construction projects, such as the installation of larger culverts. The initial, or highest-priority, improvements will cost $2 million, to be spread out over 10 years.

Other improvements could total $4 million more and would be constructed over the next two decades. The project’s improvements and maintenance will be paid for through a new utility, which will be self-sufficient and will be billed to property owners in the city.

The stormwater utility is a fee that most area cities, and the county, charge residents. North Bend officials expect the fee to be just under $10 per month for most residents, which is comparable to other area cities.

The City council has not yet decided when the stormwater utility will start, although it could begin as early as June. The council will also soon decide whether to bill residents monthly for the utility, or add it to property taxes.

The stormwater plan also includes new regulations for development that establishes requirements to lessen flooding, and it prohibits illegal discharges, like motor oil, into area surface waters. Streams, rivers, lakes, storm drains and culverts all fall under the surface-water category. In addition, the plan requires the maintenance of privately owned stormwater facilities found at housing developments and large businesses.

Final approval of the stormwater plan is expected to occur at the next City Council meeting. After that, the city must pass an ordinance forming a stormwater utility, then adopt a separate ordinance to implement drainage standard requirements for new development and redevelopment.

Residents can give input on the stormwater plan by attending a public hearing at the meeting to be held at 7:30 p.m., May 1, at the Mount Si Senior Center in North Bend. Written comments should be also be submitted before May 1 to the city’s Web site, www.northbend.ci.wa.gov, or dropped off at City Hall, 211 Main Ave. N., North Bend.