Storm and Surface Water Utility Services

Utility employee working on storm drain

What you get from the Storm & Surface Water Utility

Olympia’s Storm and Surface Water Utility provides these important services to residents and businesses in Olympia:

  • construction and maintenance of stormwater infrastructure
  • street sweeping
  • outreach to the community and business owners on pollution-reducing practices
  • water quality permit compliance
  • aquatic habitat planning and enhancement
  • tree planting
  • and more!

The Utility’s infrastructure (the built stormwater system) consists of over 160 miles of underground pipes, 7,400 catch basins, 1,400 maintenance holes, 167 flow control structures and 129 stormwater treatment facilities.

The Utility is increasingly focused on water quality improvement, aquatic habitat restoration and scheduled replacement of aging pipe infrastructure.

The majority of the Utility’s budget supports work focused on managing stormwater runoff from public streets and meeting requirements under Olympia’s National Pollutant Discharge Elimination System (NPDES) municipal stormwater permit.

This work benefits the entire community, our neighborhoods, businesses and our natural areas.

Current rate structure

Olympia’s storm and surface water service charge is collected from all developed property within City limits to finance costs associated with stormwater management.

This charge is based on the actual cost of providing the services necessary to help prevent flooding of homes, businesses and roads; minimize the amount of harmful pollutants that enter our streams, lakes and Puget Sound; and protect and restore valuable aquatic habitat.

The Utility’s rate structure is designed to be fair and equitable in distributing costs according to each customer’s relative impact. Basing rates on a property’s impervious surface and level of stormwater management establishes the link between a property’s contribution to stormwater runoff and water quality. With more impervious surface, comes more runoff. With more on-site management, comes better water quality.

Common impervious surfaces include, but are not limited to, roof tops, walkways, patios, driveways, parking lots or storage areas, concrete or asphalt paving, gravel roads and parking areas, packed earthen materials, and oiled, macadam or other surfaces which similarly impede the natural infiltration of rainfall and stormwater.

Single-family (and duplex) residential parcels

Residential properties pay a flat rate based on the average amount of impervious surface associated with single-family properties throughout the City - 2,528 square feet. The rate is discounted for plats approved after 1990 with a signed maintenance agreement covering its neighborhood stormwater facilities.

Other parcel types

Commercial, multi-family, industrial and government parcels pay a fixed administrative fee and a charge based on the property’s actual impervious surface, expressed in billing units, according to the property’s assigned rate category.

One billing unit is equal to 2,528 square feet of impervious surface - the average amount of impervious surface on residential properties throughout the City.

The utility has three rate categories. Rate categories are determined by the property’s development date, which is used as a surrogate for the level of stormwater treatment on a property. This recognizes differing stormwater management practice requirements over time. Stormwater management requirements for new development were increased in 1980 and again in 1990. Therefore, newer development is assumed to provide a higher level of on-site stormwater management (flow control and treatment) resulting in a lower charge.

To reflect the timing of stormwater requirements, the rate categories are after January 1990 (Category 1), between January 1980 and January 1990 (Category 2), and prior to January 1980 (Category 3).