NORMAN — Norman could be flush with water someday if plans to augment Lake Thunderbird with wastewater are approved by the Oklahoma Department of Environmental Quality.
That approval, however, could be years in coming. Meanwhile, the Norman City Council has to decide which of three water supply portfolio options to pin the city’s future hopes on.
“Diversity in your supply is a big strength,” said John Rehring from Carollo Engineers.
In deciding what makes sense for Norman, several public dialogues and a survey of priorities helped engineers from Carollo work toward a final recommendation for Norman.
“We looked at all the supply options that had been talked about over the years,” Rehring said.
Carollo and an ad hoc committee of Norman residents brainstormed for all possible options and eliminated what wasn’t feasible. The group packaged options to create water supply portfolios, then used screening criteria to rate and rank them.
Criteria included supply availability, reliability, certainty, timeliness, and cost–effectiveness, which allowed portfolios to be judged through quantitative and qualitative measures.
The study accounted for predictable changes like pending mandates governing levels of chromium-6 allowed in drinking water.
Well water with chromium-6 could be treated at a common facility by about 2020, Rehring said, but that process will require infrastructure the city doesn’t currently have and involves capital costs as well as additional treatment costs.
Added savings from water conservation also is anticipated.
“Norman’s already doing a lot for conservation, so it’s not as great as if we were starting from scratch,” Rehring said.
Water reuse is likely to play a large role in Norman and Oklahoma’s water future. The state recently passed gray water laws to allow municipalities to allow gray water reuse directly for landscape irrigation and similar non-potable uses.
Reclaimed water — treated sewer water — also can be used for some non-potable purposes. Further down the road, highly treated, reclaimed water could be used to augment Lake Thunderbird, Norman’s primary source of drinking water.
Currently, wastewater is discharged into rivers and eventually becomes someone’s drinking water. But the discharge points in the Thunderbird augmentation proposal would be a shorter distance. The reclaimed water would need to be treated more highly than current standards.
Lake Thunderbird has been declared an impaired body of water. Getting the DEQ to allow the use of reclaimed water to augment the lake could be difficult, even if the agency loosens up its regulations for other areas seeking such reuse.
“While it (using reclaimed water) certainly is not new on the national scale, it is new to Oklahoma,” Rehring said.
All three of the top rated water supply portfolios under consideration would use water from Thunderbird and the city’s wells. All include conservation and non-potable reuse as part of the package.
One option requires forming a regional partnership with Oklahoma City as a co-owner to build a pipeline to bring in raw water from southeast Oklahoma.
However, a lawsuit between the Choctaw and Chickasaw tribes and Oklahoma City has not been resolved. That puts a question mark into the cost and timing portion of a possible partnership with Oklahoma City.
The other two proposals include augmenting Thunderbird with reclaimed water.
Something will have to be done, and it won’t be cheap. Anticipated price tags range from $250 million to $340 million in infrastructure investment and another $21 million to $27 million per year for operations and maintenance to meet Norman’s future water needs. Those costs would be staggered out over the course of the next four to five decades.
“It’s not free or easy to keep maintaining just where we are now,” Rehring said.
Carollo’s final report is due by early November. Council members said they would like the city to host another public meeting on the water options under consideration sometime before Thanksgiving.