Wastewater Treatment Limits Business Growth in Key Center

Introducing centralized wastewater treatment in rural communities is expensive and difficult.


Key Center is feeling some growing pains. As new businesses open and current businesses expand, owners are bumping up against the limits of their infrastructure. In some cases, they’re learning the size of their septic system doesn’t match their needs.

“If you don’t have the right septic system for your property, it can be an absolute mess both for you and for the environment,” said Tacoma-Pierce County Health Department environmental health specialist Bob Suggs.

At least three Key Center businesses recently learned their existing septic systems didn’t fit their plans. Don Swensen was not able to install an espresso machine at Blend. Emily and Micah Dahl, who own 3 Clouds Bakery, wanted to lease a space in Key Center but could not use it for baking. Sarah and Bryant Anderson must install a 3,500-gallon septic tank — which will need to be pumped out — in order to open their cafe.

“We fully understand that upgrading your septic system can be frustrating and expensive, so we do everything we can to help you find the least expensive option possible,” Suggs said. “But at the same time, we want to make sure we’re doing everything we can to keep the groundwater clean.”

Key Center, designated a rural activity center, has about two dozen parcels with buildings. Nearly all the parcels have their own septic systems, though a few share a system with an adjacent building. Most, according to records available through the county, are built to accommodate a few employees with no public access to bathroom facilities. They include 1,000-gallon tanks and drain fields of about 450 square feet with a daily maximum capacity of 100 to 400 gallons. Such systems will not support businesses that prepare and serve food. Some buildings, including El Sombrero, Food Market and KP Medical Center, have larger systems and greater maximum capacity.

One solution for Key Center is a large on-site sewer system.

Suggs said that septic system design has begun to focus beyond disposal of wastewater and the fecal coliform bacteria to include reduction of nitrogen that flows from the septic tanks into the ground water and then to Puget Sound or neighboring lakes, causing problems including algae blooms.

Some landowners have brought up the possibility of building a sewer system to serve Key Center, noting that drain fields take up a significant amount of otherwise buildable space, and raising the concern that if there is drain field failure there is no good back-up plan.

Pierce County Councilman Derek Young and Suggs said that a sewer system with water treatment in Key Center is not feasible.

Larry Altose, communications manager for the Washington state Department of Ecology, echoed the words of the county.

“Generally speaking, introducing centralized wastewater treatment in rural communities is very expensive and almost never easy,” Altose said. “Sometimes new sewer systems are infeasible because of Growth Management Act zoning or water supply constraints. The facilities themselves are expensive to build and maintain and they require employing a certified operator to manage them properly on an ongoing basis. These costs can fall particularly hard on rural communities because of the small number of rate payers.”

One solution for Key Center, suggested by both Suggs and Altose, is a large on-site sewer system (LOSS) administered by the Washington State Department of Health.

A LOSS is designed to allow for a flow of 3,500 to 100,000 gallons per day and to serve from 10 to 370 homes or equivalent flows from other clusters of buildings. Flow from all buildings would be piped to a common receiving tank and then sent to a single drain field. Key Peninsula Middle School and Penrose State Park are each served by a LOSS.

Leigh McIntire, on-site sewage and well permitting program manager for the health department, said that environmental health specialists can partner with businesses to find the best approach to their septic needs. He cited Graham as an example. “They have multiple commercial systems out there that work together to serve the businesses there. Depending on the specific circumstance, that can be much more cost effective than installing a LOSS.”

There is currently a sewer and wastewater treatment plant near the southwestern tip of Key Peninsula. Taylor Bay Estates, a community with 155 lots, 110 homes and 250 residents, installed its system 50 years ago. The system is aging, has needed a number of repairs, and now requires a certified operator to be on site at least five days a week, according to Don Tjossem, a member of the Taylor Bay sewer committee.

Although the flow from the system into Taylor Bay has met basic state requirements, it does not meet the requirements of the National Shellfish Sanitation Program and the geoduck beds cannot be opened unless the situation is remedied.

The Washington State Department of Natural Resources funded a feasibility study to look at alternatives to upgrade or replace the system. The 2019 report recommended some short-term repairs and noted that although the system was probably adequate for several more years, it would need to be replaced.

DNR did not recommend upgrading a system that would continue to send effluent into Taylor Bay, as the costs could be prohibitive to construct a new ocean outfall without incurring a natural resource damage assessment.

Tjossem said that Taylor Bay Estates will complete repairs recommended by the study for the short term. The cost of replacement is significant.