The deadline is fast approaching for the city to decide how to stop leakage from its Brunswick Reservoir into the Carson River.
Some residents who live in the Mexican Dam subdivision behind Prison Hill, where work is being proposed, say the plan will result in their water quality being harmed by treated wastewater.
"The shame of it is that as precious as water resources are in the West, to contaminate a clean aquifer is a sin," said resident Steven Brandon.
The 88 parcels affected take water from a private well.
Residents are concerned about plans to move the water through their area using rapid-infiltration basins to allow treatment and disposal of the effluent, or wastewater. Nitrogen would also need to be removed, according to the city's water-reuse master plan update.
Rapid-infiltration basins allow wastewater to percolate through the soil, and the treated effluent then drains through hydraulic pathways to groundwater or surface water, according to the Nevada Department of Conservation and Natural Resources Division of Environmental Protection.
"Don't take a perfectly good drinking-water well and ruin it," said resident Roland Sala. "It doesn't make any sense. We don't want to be the city's scapegoat. We really, really don't want it."
Six different alternatives are presented in the plan. All include use of the rapid-infiltration basins; some include lining the reservoir and building another reservoir near the Carson City Rifle Range. They range in cost from $8.9 million to $25.7 million.
Brandon said research on infiltration basins isn't complete, and that there is no documentation about how materials not removed, such as human hormones, will lessen the groundwater quality.
The salts not taken out of the effluent will harm the residents' drinking water-collection system, he also said.
The city reclaims 5,800 acre feet of water a year, except for the 2,000 acre feet that seeps out of the reservoir each year. The city has been able to find places on which to sprinkle the remaining reclaimed water.
"The plan is just to appease the state," Brandon said. "The city has wasted a lot of time and money."
In 2003, the state ordered Carson City to control seepage from the reservoir by lining it - if it's to continue to be used to store up to 3,800 acre-feet of wastewater from 13 reuse sites in Eagle Valley.
Though it appears the infiltration basins will be used in some quantity, improvements planned at the city's wastewater treatment plant might ease the situation, said Tom Hoffert, public works operations manager.
Bids on plant improvements are expected to be sought this winter. Modifications to the plant design to remove phosphorus from the effluent would have to be added, he said.
"We're pursuing both options because we're still under deadline," Hoffert said.
It's possible both plant improvements and infiltration basins could be used to solve the problem, he said.
You can help
• Public comments are being sought about the plan until April 25. For information about the plan, call Public Works at 887-2355.
• The Carson City Board of Supervisors is expected to decide on a method during its meeting June 1. A plan must be submitted to the state by June 30.
• Contact reporter Terri Harber at tharber @nevadaappeal.com or 882-2111, ext. 215.