What is stormwater?

Water that falls during rain or snow storms is stormwater. But once it falls from the sky, where does all that water go? The way that water moves through the landscape (otherwise known as hydrology), and the ways that people change this movement can determine whether water is a welcome resource or a nuisance or even a hazard. This diagram shows how water moves through a typical forested watershed in the Puget Sound area:

	Hydrology of a Forested Watershed in Puget Sound Lowland Credit: Curtis Hinman, Washington State University, Pierce County Extension, 2005.

Once an area is developed with houses, roads, and parking areas, the way water moves through it looks more like this:

Watershed Hyrology for a typical suburban development in the Puget Sound Lowland Credit:  Curtis Hinman, Washington State University, Pierce County Extension, 2005.

Why do we have stormwater problems in Kirkland?

Water is a good thing, but too much of a good thing can cause problems. In developed areas such as the City of Kirkland, we have many hard surfaces such as roadways and rooftops that do not allow water to soak into the ground. Lots of water running over hard surfaces can lead to flooding, stream channel damage, and water quality problems.

Bank erosion along Juanita Creek

Flooding during a December 2007 storm

Anything spilled on a paved surface may wash into the nearest waterbody. In this case, cooking oil was spilled in an alley in downtown Kirkland. The oil would have washed into a storm drain and then into Lake Washington if it had not been discovered and cleaned up.

Where is the Creek in My Neighborhood?

Please refer to the Streams and Wetlands Map (PDF) to find the creek in your neighborhood. There are 9 major watersheds that feed creeks of various sizes in Kirkland. For some interesting facts about each of these watersheds, see Chapter 3 (PDF) of the 2005 Surface Water Master Plan.

What is the City of Kirkland Doing to Help Manage Stormwater?

The solution to stormwater problems will take help from all of us. Kirkland’s Surface Water Utility was formed in 1998 in order to help to address flooding, water quality, and aquatic habitat problems and to protect public stormwater systems. The 2005 Surface Water Master Plan provides detailed information about Utility programs, and here’s an overview of major programs:

Education and Stewardship – We get the message out about stormwater problems, and involve the community in projects that encourage behaviors that protect and cleanup stormwater. Examples include streamside cleanup and planting events, natural yard care seminars, and creation of a watershed pledge.

Underground vaults are often used to detain and slowly release stormwater in order to prevent flooding

Development and Construction – City staff review development proposals to make sure that the quantity and quality of runoff is controlled. We also encourage the use of Low Impact Development techniques to keep stormwater from becoming a problem in the first place. See our Development page for further information.

Maintenance and Operations – Crews work to maintain more than 10,000 storm drains and over 190 miles of pipes and ditches that make up our public stormwater system. They inspect lines with TV cameras to find and fix problems before they cause flooding, and protect water quality by removing dirt and oil from storm drains. Help us to do this job better by adopting a storm drain near your house or by reporting a problem.

Water Quality Investigation - We respond to calls from the public and investigate potential sources of pollution by conducting sampling and by inspecting businesses. We also regularly inspect facilities on private property to make sure that they are working properly. It is easier and more cost-effective to control pollution at its source, rather than to remove pollutants from stormwater later on.

Capital Improvement Projects - The Stormwater Utility constructs capital improvement (CIP) projects to solve flooding problems, improve water quality, and to improve fish habitat. Check out a list of current projects, and look at Planned Surface Water CIP Projects (PDF).

Watershed and Utility Planning - Kirkland is involved in various projects to target spending for the maximum benefit. See examples of past products from this work including the 2005 Surface Water Master Plan, the Pollutant Hot Spot Identification Study (PDF), and the LID Feasibility Study.