Another aquifer recharge site has been approved for the Upper Snake River region.

The Idaho Water Resource Board on March 31 approved $1.7 million in American Rescue Plan Act funds to develop the 55th Road recharge site about seven miles northeast of Idaho Falls.

The project would use an old 8.6 acre gravel pit that Enterprise Canal Co. has purchased.

About half the recharged water would remain in the Eastern Snake Plain Aquifer for 1.5 to 2 years before returning to the Snake River, according to a release from the board.

In 2015, a coalition of surface water users reached a settlement agreement with groundwater users, who hold junior rights. Twin Falls Canal Co., a key player in the surface water coalition, supports adding aquifer-recharge capacity in the Upper Snake and its Blackfoot-to-Neeley reach.

“That part of the river is critical to us. It’s a hot spot that needs to be addressed,” said John Simpson, an attorney for the company. “Shorter aquifer-retention times are OK in that area because it will add to surface water flows.”

More surface water flows for Snake River irrigators could help reduce conflict with groundwater irrigators, he said.

The board has recharged the Eastern Snake Plain Aquifer between irrigation seasons since 2014, increasing aquifer levels and surface flows. During years when flood-control releases are done, the intent is to move as much water into the aquifer as possible, a benefit to surface and groundwater users.

Idaho Ground Water Appropriators officials told board members they support development of additional recharge sites to increase annual recharge volumes.

Idaho Power Co. officials said the board should consider the importance of winter surplus flows for other needs such as water quality, recreation and hydropower.

More reliable recharge sites in the Upper Snake River Valley have been sought for years.

Above American Falls Reservoir, water is only available for recharge when flood-control releases occur, about every other year, Wesley Hipke, recharge program manager for the board, said in an interview. Otherwise, this water is captured in Upper Snake reservoirs for use the next irrigation season.

“Since the water for recharge is only available intermittently, that is why the Water Resource Board wants to develop as much recharge capacity above American Falls as they can,” he said. “During flood releases, there is an abundance of water, and that is needed to make up for the dry years.”

An advantage of the 55th Road Site is it provides a fairly quick impact to the aquifer, helped by where it is located in relation to subsurface geology, Hipke said.

It is the fifth ARPA-funded recharge project and third in the upper valley.