Norman — Lake Thunderbird’s well-earned nickname, “Dirtybird,” may not apply in six years, according to computer model projections. The model projections and recommended requirements for reducing lake pollution were developed by the Oklahoma Department of Environmental Quality and Dynamic Solutions LLC.
Regulations implemented as a result of the study will affect Moore and south Oklahoma City as well as Norman because all three of those municipalities discharge stormwater into Lake Thunderbird’s watershed.
The computer modeling is part of a special study to look at pollution levels feeding into Lake Thunderbird, how much pollution the lake can theoretically handle and how to reduce the pollution to meet state and federal water quality requirements.
Known as the Lake Thunderbird TMDL Project, the study measured the Total Maximum Daily Load of pollutants going into the lake from various sources, as well as general run-off from the natural environment. Norman, Oklahoma City and Moore are the primary point sources of pollution.
In 1972, Congress adopted the Clean Water Act and, with it, some target dates for water-quality achievements.
“Congress set some pretty ambitious goals,” DEQ Watershed Manager Mark Derichsweiler said.
Goals included having fishable, swimmable water quality wherever it was attainable by 1983 and eliminating the discharge of pollutants by 1985.
“We’re still a little behind on the 1983 goal, and we’re really behind on the 1985 goal,” Derichsweiler said. “We have somewhere over a thousand impairments in this state. Lake Thunderbird is one of the priorities.”
Thunderbird is designated as a sensitive water supply because it provides drinking water for Norman, Midwest City and Del City. It has been classified as impaired because of high levels of sediment (turbidity), algae (chlorophyll a) and low oxygen levels. The algae growth is a result of pollution by nutrients, in particular phosphorous and nitrogen.
“Lake Thunderbird doesn’t meet water-quality standards,” Derichsweiler said.