Water samples from the Popo Agie Riverton about one mile downstream of Lander indicated elevated levels of E. coli bacteria. (Ernie Over photo)

(Lander, Wyo.) – A public notice from the Wind River Environmental Quality Commission posted on County10.com on Monday indicated E.coli bacteria levels exceeded Tribal Water Quality standards for primary contact recreation activities about one mile downstream from Lander.

“Over a 30 day average, there probably is no issue, but the bacteria level certainly came up high on two samples that we tested. Some tests were high, others were not. We’ll continue sampling,” said Ryan Ortiz, executive director of the WREQC.

“We’re not saying that people should stay out of the water, the two samples were a bit high and we want people to use their own discretion. We want to avoid anyone getting an illness,” he said.

In the public notice, the WREQC indicated they would collect weekly samples to establish a 30-day geometric mean. Ortiz said the WREQC uses U.S. Environmental Protection Agency-approved standards.

See the public notice here.

Water sampling in and adjacent to the City of Lander is done by the Popo Agie Conservation District and to date their tests have not exceeded water quality standards.

“We do monitoring May through September with weekly sampling using the Wyoming Department of Environmental Quality’s methodology,” said Jeri Trebelcock, conservation district supervisor. “That standard says we should not exceed 126 organisms per 100ml of water over a 60 day geometric mean.”

Trebelcock said the level of the river this summer “has been surprisingly high, through last week,” with continued runoff from the Wind River Range. “When we exceed that Wyoming DEQ Standard, we would contact Fremont County Public Health and show them our data and then they would make a decision if contact with the river water should be avoided.”

Trebelcock said the standard quoted by the WREQC appeared to be based on single samples and not the 60 day geometric mean, which is the new standard set by the Wyoming DEQ for 2014, she said. “That does not mean that their samples aren’t valid, but just that they are not based on the 60-day geometric mean.”