COLUMBIA, SC — A long stretch of the Broad River through Columbia is going to turn into a stagnant puddle next week while repairs are made to a broken gate on the diversion dam.
River advocates are concerned about damage to wildlife in a rocky section of the river where several species of fish are beginning to head upstream to spawn and where rare rocky shoals spider lilies have begun to thrive in recent years.
“Taking the water out of the river is never good for wildlife,” said Congaree Riverkeeper Bill Stangler, whose organization serves as a watchdog for the lower Broad, lower Saluda and Congaree rivers.
The health of that nearly two-mile section of the Broad has improved immensely in the past decade, because federal relicensing led to changes in the operation of the Columbia Canal and its diversion dam. Lockhart Power, a small Upstate-based power company that took over the operation of the dam from SCE&G in 2011, is required to maintain a certain level of water flowing in the river below the dam.
But Stangler received word this week that Lockhart has declared an operational emergency, allowing it to take extraordinary steps to make repairs. The work is scheduled for Monday through Friday of next week, said Bryan Stone, chief executive officer of Lockhart.
Stangler wondered why the company couldn’t bring in equipment to pump water over the main portion of the dam during repairs. Stone said the company looked at all alternatives, and cutting off flow downstream during the repairs had the least environmental impact.
To maintain flow when the Broad River is low, a notch is built into the canal diversion dam. An air bladder raises and lowers a gate in that notch to control the amount of water allowed through. That bladder broke sometime last month.
During the five-day repair effort, most water reaching Columbia will be diverted through the canal instead of down the Broad River itself. Some water will flow through the diversion dam’s small fish ladder device and some might seep around the western edge of the dam, but the stretch of river from the diversion dam through its confluence with the Saluda River will be mostly stagnant.
“These are the exact conditions that relicensing was supposed to avoid,” Stangler said.
How the five-day change will impact fish and plant populations along the river is unclear. But Stangler said the constant flow required under the relicensing of the dam a few years ago is a major reason for the improvement in the health in that section of river.
The river behind the diversion dam will have to be dropped 3 to 6 feet so workers can get to the bladder control device, Stone said. The repairs are estimated to take four days.
While the effort is scheduled for Monday through Friday of next week, the timing is subject to change based on recent heavy rains, said Stone, whose company also was dealing Friday with ice damage in Upstate South Carolina and central North Carolina.