“Last fall we presented to council a request for funding for the preliminary design of an effluent disposal line,” Snowflake Town Engineer Rob Emmett noted during the April 12 town council meeting.
The wastewater treatment plant treated effluent, or reclaimed water, is currently reused as irrigation water for farm land situated to the south of Flake Road, west of State Route 77, east of Red Hill and north of the Brimhall sand and gravel pits, Emmett explained in backup material for the meeting.
“Arizona Pollutant Discharge Eliminate System permitted the town to dispose of effluent to an unnamed tributary to Cottonwood Wash,” said Emmett. “Both of these disposal approaches are either in jeopardy or are unusable.”
Emmett explained that current permits allow for up to 308,000 gallons per day (gpd) and the town generates approximately 270,000 gpd.
Property owners where the effluent was disposed are in the process of developing a sand and gravel mining operation, and the unnamed tributary does not have the ability to flow into Cottonwood Wash because of an existing sand and gravel pit, whose owner’s attorney notified the town not to use the tributary for effluent disposal because of lack of easements and discontinuous drainage conveyance facility to Cottonwood Wash.
Town staff members, working with Tetra Tech, have been exploring other options, and on Nov. 9, 2010, the council approved an agreement for Tetra Tech to analyze potential disposal options.
Staff identified two potential disposal alternatives, which involve redirecting the effluent to another location along Cottonwood Wash. The first option would use the existing irrigation line in front of the treatment plant and the effluent would be conveyed to the south toward the wash. The consultant’s preliminary findings show this is not feasible, though, because of pipe grade and pipe sloping the wrong direction, so effluent would need to be pumped, irrigation pipe is not rated as a pressure pipe and would require replacement and the underlying easements, either recorded or by prescription, for the irrigation line don’t provide for wastewater use.
Emmett said the second option would be to install a new pipeline within rights-of-ways for Snow Lane and SR 277, which appears to be the most economically feasible. The effluent would gravity flow and be discharged to the north of the SR 277 bridge over Cottonwood Wash.
“To finalize the design and allow for construction to proceed, staff requested a proposal from Tetra Tech to complete the work. Tetra Tech’s proposal includes the development of 100 percent construction plans and specifications, assistance with ADEQ (Arizona Department of Environmental Quality) approval and an ADOT (Arizona Department of Transportation) encroachment permit, the development of a storm water pollution prevention plan for construction, attendance at pre-bid and pre-construction meetings, construction staking, preparation of record drawings or as-builts, and project management,” Emmett noted.
“This, to me, is our short term, as well as our backup plan,” said Town Manager Paul Watson. “Long term there has been discussion that we need to find a better use for our reclaimed water, and one of the primary objectives would be to put it on the golf course.” He went on to say that they would need greater storage capacity and a rough estimate to take the effluent to the golf course would be approximately $3 million.
“To me, even if in the future we have peak periods or something happens, we need an alternative to release that water as stated,” said Watson. “It’s coming every day whether we want it or not.”
A motion to approve the contract amended with Tetra Tech Engineering for the final design and construction services for the wastewater treatment plant treated effluent disposal line in an amount not to exceed $14,757 was approved unanimously.
