Central Oregonian - What does the Crooked River Wetlands Complex do?

This article was published on: 02/8/22 8:48 AM

The Crooked River Wetlands Complex was built to provide the city of Prineville with more wastewater capacity at a lower cost

By Ron Halvorson

Although we’ve had some mild days, it’s still the dead of winter and there’s not much going on at the Wetlands — at least that we can see — thus, this is a good opportunity to address a topic on everyone’s mind: why is the complex here and what does it do? You’d be surprised how many daily users of the facility have no idea, and so here’s a brief attempt to change that.

First a bit of history.

Old-timers might remember the first sewage treatment plant constructed in 1960. Raw sewage was screened for the big chunks, treated with chemicals, sent to a couple of treatment ponds, and then into the Crooked River. No fuss, no muss. This is basically the same facility you see a mile or two up the road.

For some reason, the governing bodies didn’t think this was the best idea in today’s modern world, and so our growing community needed a different approach. City leaders came up with a great idea that instead of constructing a costly, newer facility, the treated effluent could irrigate a golf course. Meadow Lakes Golf Course came online in 1993 and voila! The problem was solved. Fore!

But as we all know, Prineville has continued to grow and with it the need for additional sewage treatment capacity. Once again the city leaders came up with an innovative and fiscally-responsible idea: treat and dispose of treated effluent using a natural wetlands process. Completed in 2017, the Crooked River Wetlands Complex not only is a success at what it was designed for, but it also provides great recreational opportunities.

So now you’re at the Wetlands. What do you see and what’s going on?

If you’re at the parking lot, you’re surrounded by eight relatively small ponds scattered close by with cable “fences” on their perimeters. Water in these ponds comes from the “horseshoe pond,” a fenced pond adjacent to the Wetlands that contains treated effluent from the treatment facility upstream. This water is essentially the same as what is applied to the golf course — not dangerous, but you wouldn’t want to drink it.

These eight “treatment” ponds are lined with bentonite clay so the water doesn’t seep out, providing time for the microorganisms and plant life to clean it. Ponds 1, 4, 5 and 8 are shallow, provide the most vegetative treatment and also support aerobic (requiring oxygen) bacteria. Ponds 2, 3, 6 and 7 are deeper, have less vegetation and less oxygen, and provide a great place for anaerobic (without oxygen) bacteria. In general, the water moves through one of two “trains” – ponds 1 through 4 or 5 through 8 – with the anaerobic treatments in the middle. Valves and gravity allow the operators to send water when and wherever they want. It’s as much an art as it is a science.

After the specified treatment and time in these ponds, the water is allowed to flow to one or more of the seven “disposal” ponds downstream. Here it sits as it slowly seeps into the ground (percolates) and eventually enters the adjacent Crooked River. Continual analysis at several test well locations shows its quality to be outstanding, and in a small way, it actually improves the water quality of the river.

This is a pretty shallow (pun intended) explanation and if you need to know more, a Wetlands volunteer can help or at least point you in the right direction.

Bird-wise it’s been pretty quiet. A team of three visited the Wetlands on Dec. 31 as part of the local Christmas Bird Count and tallied 1,412 birds representing 51 different, but fairly common, species. That’s not bad considering it was cold and snowing hard that day. Overall, 192 different birds have been documented at the Wetlands since its opening.

One bird of note was found during the monthly bird walk on December 4 – a Least Sandpiper. Now I wouldn’t go out of my way to see this bird, but those in the know were pretty excited as this is an unusual sighting for this time of the year. Common, especially during their spring and fall migrations, a Least Sandpiper with any sense, would find itself in warmer climes by December, one would think. Remember: bird walks are held on the first Saturday each month, beginning at 9:45 a.m. Binoculars are provided.

Given the enthusiasm of both the contestants and volunteers for last year’s photo contest, we have decided to do it again this year. It will be much the same as last, but the timeframe will be expanded to encompass the entirety of 2022. Specific details will be in the next Tule Talk but this is a heads-up to get out there now and start taking pictures.

That’s it for now. Spring is just around the corner, and we all know that means more snow and colder weather is on the horizon!