Are you ready to water the lawn with treated sewage?

It seems as if it has taken forever for someone in Kitsap County to put treated sewage to beneficial use, but a demonstration project on Retsil Road in South Kitsap is just around the corner. Check out my story in Saturday’s Kitsap Sun.

Darren Noon of Pape and Sons Construction Co. welds a section of "purple pipe" along Retsil Road in South Kitsap, the first reclaimed water project in Kitsap County.
Kitsap Sun photo by Meegan M. Reid

Local water experts were contemplating uses for highly treated wastewater even before “low-impact development” became a common phrase for infiltrating stormwater into the ground.

LID has caught on fairly quickly as a method of keeping polluted stormwater from reaching our streams and Puget Sound. The concept got an extra push from new stormwater regulations, which have greatly increased the cost of conventional pipe-and-pond methods of stormwater management.

The less-touted benefit of LID is groundwater recharge, which boosts our long-range water supply.

Kitsap County’s Watershed Management Plan (PDF 147 kb), developed in 2005, estimated that Kitsap County’s sewage treatment plants release 8 million gallons of treated water into Puget Sound each day. That’s enough to increase the base flow of 10 streams by 10 cubic feet per second, raise aquifer levels throughout the county or launch a new industry without touching our drinking water supplies.

“The most significant barriers to recycling wastewater are the cost of infrastructure and additional treatment, as well as public perception,” the report states. “Elected officials in WRIA 15 (the Kitsap Peninsula) have expressed support for public education about reclaimed water.”

The report mentions that highly treated effluent from the Central Kitsap Wastewater Treatment Plant near Brownsville could be used to supplement streamflows in nearby Steele Creek. But more recently Kitsap County and Silverdale Water District have begun working together on a plan to pipe the water into the heart of Silverdale, where it can be used to water ballfields and landscaping.

That’s also the initial plan put forth by West Sound Utility District, as I mentioned in Saturday’s story. Using wastewater for irrigation cuts down on peak demand, which is what drives water utilities to drill new wells. Needless to say, drilling deep wells comes at a tremendous expense — an expense that grows greater as Kitsap County approaches the limits of its groundwater supplies in some locations.

To many people, using reclaimed wastewater seems like a novel idea, especially in an region known for its rain. People remain squeamish about getting anywhere near sewage water, even if it is treated. But I don’t believe it will take long for people to accept the idea of using treated wastewater for irrigation, once they realize it is treated to basically the same level as drinking water.

On the other hand, drinking treated effluent becomes another issue, even though it has been done indirectly for years in many places. If you live in a town on the Mississippi River, your local utility may be drawing water out of the river for your consumption just downstream of where a sewage treatment plant is dumping its effluent.

There are several other places where reclaimed water is mixed with freshwater, such as in a reservoir, then drawn back out for drinking. Ironically, putting the wastewater into a reservoir makes it seem more palatable, even though it probably was cleaner before. Treating the water in the reservoir is essentially treating the wastewater again — although water is just water in the end.

For a description of reclaimed water systems in the U.S. and elsewhere in the world, check out a fact sheet compiled by Queensland Water Commission, Australia: “Water recycling: Examples from other countries” (PDF 592 kb).

A community in Texas made news across the country last week, when reporter Angela Brown of the Associated Press wrote about a new $13-million water-reclamation plant to turn effluent into drinking water, the first to be built in that state. Really, it is nothing new, as Angela herself points out.

What I have not found anywhere so far is a direct use of reclaimed water. That’s what you would get by pumping the highly treated wastewater directly into a municipal water system’s piping network. From a health standpoint, there would be nothing wrong with that, provided the water could be shut off in the event of a problem at the treatment plant. No doubt this kind of direct use will be a little harder to get used to, even in areas where water is scarce.

Alix Spiegel of National Public Radio does a nice job analyzing the psychology behind the aversion to using treated wastewater and why people are more accepting of indirect use. Read or listen to “Why Cleaned Wastewater Stays Dirty In Our Minds .”

5 thoughts on “Are you ready to water the lawn with treated sewage?

  1. Hmmm,

    I believe that the Bremerton sewage treatment plant has been using treated wastewater to irrigate the area next to the Hwy 3 merge for many years. At least that is what I am assuming from the signs that say “non potable water”

  2. That’s a reasonable assumption, Gregg, but I was told that “purple pipe” was installed along the highway during development for use when reclaimed water becomes available at the Bremerton treatment plant. As of now, that plant does not treat its wastewater to a high enough quality.

  3. Since I worked in this field for a number of years, I do have a strong opinion on the topic. First there are a number of drugs, viruses and chemicals which are not removed in even tertiary treatment, secondly some of us don’t waste our energy or water on decorative lawns. Everything I grow is edible, I use drinking water hoses and want potable water flowing through them. We used to clearly state treated water and solids were to be used only where they would not come in contact with crops. That message got “forgotten” in the early 90’s with the move to save $$$ through reuse. It is still a valid concern.

  4. Gregg,

    I stand corrected. Pat Coxon manager of Bremerton’s Wastewater Utility tells me that the property along Highway 3 in front of Parr Ford is watered with Class B reclaimed water during the dry season. Because of its lower quality, the public can have no access to this property, which is fenced off.

    The water along Retsil Road, on the other hand, will be Class A reclaimed water, a higher quality that differs little from drinking water, according to state experts. No public-access restrictions are needed.

  5. We broached the idea of drinking treated water directly from a sewage treatment plant in this Aug. 17 blog entry.

    Now Dylan Walsh on the New York Times Green blog calls our attention to a new report that suggests highly treated sewage effluent from advanced municipal systems poses no greater health risks than those of many existing water supplies.

    Check out the news release, with links, from The National Academies.

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