The Boise sewer system is a collection of more than 900 miles of pipes that weave underneath the city. Along with regular system maintenance, Public Works makes major repairs and is in charge of designing the system.

Since 1985, Public Works has also regulated industrial and commercial wastewater discharges into the sewer system through its EPA-approved pretreatment program. In addition, Public Works also sets the sewer rates for residential and commercial users and administers sewer billing.

Sewer Fees (Industrial or Commercial Businesses)

In general, fees paid to the city prior to connection to the sanitary sewer system consist of two major components: connection (capacity) fees, and assessment fees. These fees do not pay a contractor to complete the physical connection from the building to the edge of the right of way.

Connection Fees

The connection (capacity) fee is made up of three components including the trunk fee, the treatment fee and the interceptor fee. Each of these fees is paid by both new and existing development at the time of connection.

  • Trunk fee – Designed to recover the cost of over-sizing sewers to carry waste to the treatment plants and to recover a portion of the cost of the sewers in existing neighborhoods.
  • Treatment fee – Designed to recover the capital cost of constructing treatment facilities, providing room at the treatment plant for the additional waste.

Commercial connection (capacity) fees are calculated per plumbing fixture based on the estimated flow and strength of the waste. Food service and industrial type services are calculated differently.

Assessment Fees

The assessment fee is based on the average cost of an 8-inch sewer line in the street and will include a service line to the edge of the right-of-way of your property. The assessment is an average cost to construct pipe, manholes, pavement restoration, and permits as well as design, survey and inspection of the project. The assessment fee is an average cost of projects rather than dividing the cost of the particular project which serves your area.

Not all properties will pay an assessment fee. New subdivisions are required to pay the assessment and to construct sanitary sewers within the subdivision boundaries at the time of development. The costs for sewer are then included in the cost of your subdivision lot. If you are building on an existing lot which is being split or connecting an existing building to sanitary sewer, you should expect to pay the assessment component of the fees.

Contact Information


For information on design requirements, please call (208) 608-7150.

Connection Fees or Extensions

For information on connection fees and / or extensions, please call (208) 608-7150.

Sewer Complaints

For complaints related to sewer odor, line back-ups or construction related issues, please report online or call (208) 608-7200.

Report Online

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