Frequent visitors to the Barnes Butte Recreation Area might have noticed a new water feature.
Just east of the parking lot, where a paved trail bends sharply to the north, a new pond has suddenly emerged. A closer inspection will reveal it is fed by a canal coming from the north.
And while this new water feature may be a surprise to visitors, it wasn’t to city leaders.
Amidst construction of the new Combs Flat Road extension, the city of Prineville wanted to solve two different riddles. One issue involved building the road across a local wetland that flows north to south along the west end of the Barnes Butte Recreation Area. Not only would a road cross the wetland, Ochoco Irrigation District (OID) would need to trench about 15 feet deep to bury 78-inch diameter canal pipe. The canal pipe, which will follow the roadway footprint, is replacing the open canal that currently snakes through the area.
“In order for them to install the OID canal pipe and construct the base of the road prism for the roadway, they have to dig down into the wetlands,” explained City Public Works Director Casey Kaiser. “In order to do that, they need to do what is called dewatering – they need to pump all of that water out of there. The big challenge with dewatering is what do you do with the water?”
That is where the second riddle enters the picture. Community members had asked, during the formation of the Barnes Butte Recreation Area, to run water through an empty canal, on the east slope of the property near a paved bike and pedestrian loop, into an empty pond. Both had been dry for at least 20 years. The challenge had always been finding a way to do it and a reason to justify the expense and work involved.
Once dewatering entered the picture and the city had to figure out what to do with the water, they saw an opportunity. Would it work, they asked project contractor Taylor Northwest, to pump water out of the wetland upstream from the road project, and push it up to the dry canal, where it would flow into the empty pond?
“Then it can overflow from the top of the pond and run back down into the wetland,” Kaiser proposed.
Taylor Northwest thought it was a great idea and embraced it. A temporary generator and pump was installed at a pond upstream from the wetland road crossing, reducing the outflow into the wetland as much as possible. The contractor then installed an underground water pipe that travels about 25 yards south then turns another 50 yards east, where it can feed the canal.
Then, to account for the remaining trickle of water still flowing into the wetland, a series of dewatering wells were installed near the road crossing. About 20 feet deep, the wells are responsible for pulling any remaining groundwater out of the construction zone.
The idea wasn’t a sure thing, so city leaders had their fingers crossed.
“We had always heard a lot of speculation that his canal was very inefficient – and I don’t even know where that came from,” Kaiser said. “Somewhere along the way, someone told the city that, and it passed around the city. So, we were a little bit worried that the small amount of water we were pumping wouldn’t be enough to make it all the way down to the pond.”
It turns out that the rumors were off the mark. The canal has been efficient enough so far that the city is hoping to make the temporary solution a permanent fixture.
Assuming no issues arise, once the road construction and need for dewatering concludes, the city would run a permanent power source to the wetland feeder pond and install a permanent pump that would continue to move water to the canal, into the pond and overflow back into the wetland. The only difference is enough water would be left in the feeder pond to allow flows through the wetland once again.
The other good news is that while the feeder pond is located on private property owned by Debaca Land and Cattle, the city has an easement leading up to a portion of the pond alongside a power pole and an irrigation right that allows the municipality to pump water from it.
“This is just wone of those things where everything came together just right,” Kaiser concluded.
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