Cheney's purple pipe

CHENEY – The City Council gave its approval to several projects last Tuesday, July 28, allowing a residential development to proceed along with a long-anticipated move towards utilizing reclaimed wastewater for irrigation purposes at public places.

The latter involved accepting a pair of bids to install filtration systems at the city’s wastewater treatment plant allowing future construction of a “purple pipe” system from the plant to Cheney parks and other publicly owned spaces requiring irrigation. That system could be expanded to include Cheney School District and even Eastern Washington University facilities.

The council approved a $629,965 bid from Aqua-Aerobic Systems for installation of a pile-cloth disk filtration system. According to the company’s website, the system works by passing wastewater through a chamber containing a number of cloth covered discs on a center spindle.

Waste particles in the water pass through the cloth and are filtered out, with the water then exiting the chamber. The discs are subsequently cleaned using a rotational-scrubbing backwash method.

Aqua-Aerobic Systems was the highest of two bids, with a system provided by Nexom the low bidder at $349,569. An evaluation of bids by the city’s consultant Esvelt Environmental Engineering determined Nexoms’ bid was non-responsive in a number of areas and disallowed.

In awarding the bid, council approved a $695,000 appropriation request from the Public Works Department that included money the quoted work plus 10 percent contingencies.

Council also approved a $1,114,908 bid from Enaqua for supply and installation of an ultraviolet disinfectant system at the plant that will be used in conjunction with the pile-cloth filter system to clean the wastewater to drinking water standards before it is discharged into the purple pipe system. Enaqua was the only bidder on the UV system since it was the only manufacturer that could meet the specifications, Public Works Director Todd Ableman said.

The resolution approved a $1.25 million appropriation for the system, which also included 10 percent contingencies. Both systems are funded by a direct appropriation grant the city received from the state Department of Commerce.

Ableman said both projects will need to go through extensive specification approval processes before work can begin.

“It is quite a turn around to that end, so I would imagine these pieces of equipment wouldn’t be showing up until next year some time,” he said. “It’s quite an order.”

Councilman Paul Schmidt pointed out that the UV system can be used for the entire plant system, not just water distributed for irrigation. He pointed out both projects put appropriations well over $2 million, but supposed neither would require the need for any contingencies.

“I would be surprised if we even went over it (bids),” Ableman said. “I think what they bid, unless there’s something that we had to add on, but I think it’s a pretty thorough specification for the full component.”

Council also passed a resolution approving final plat for the View Acres 5th Addition residential project located at the end of Ridgeview Drive northwest of Salnave Elementary School. The council originally postponed final plat approval for the development at its July 14 meeting over a desire to hold a discussion about water rates and receive and approve water hookup charge changes stemming from a consultant report. Council conducted both of those earlier in the July 28 meeting.

Final plat approval will allow the developer to proceed with construction of homes on 16 of the 28 lots on the 14.2-acre site.

“Bigger lots too, so there should be bigger houses up there,” Mayor Chris Grover said.

John McCallum can be reached at [email protected].