Pond conversion almost complete

WALTERVILLE: After almost two years of extensive planting to establish native trees, shrubs and wetland plant species at the Walterville Pond five miles east of Springfield, the conversion from a man-made pond to a naturalized wetland is nearly complete.

The restoration project was started in 2014 to improve the natural habitat value while retaining the area’s recreational benefits, according to Eugene Water & Electric Board officials.

EWEB built the pond several years after completing the Walterville Canal to store water to supplement generation at its Walterville Powerhouse. Use of the pond for power generation ended several decades ago, but the utility continued to maintain levels by pumping water from the adjacent canal. The 4-mile-long canal diverts water from the McKenzie River to the power plant, located on Camp Creek Road.

In 2012, federal dam safety regulators classified the pond as a “high hazard” facility after concluding it could cause a breach or a potentially catastrophic failure of the canal embankment.

The Federal Energy Regulatory Commission was worried a rupture at the pond or the canal would present a public safety risk with the danger of significant property damage to the Walterville community. At that time, EWEB did some initial lowering.

In 2014, the utility started draining the pond in increments twice a year, aiming to bring it near the water level of the canal. The gradual lowering was coupled with a planting scheme that included ash and Ponderosa trees, along with native shrubs such as willow and dogwood, and native wetland species. The process allowed warm-water fish and animals to adjust to a smaller pond while retaining the recreational and natural habitat benefits the area provides.

“We wanted to establish native plant material that can compete with the ubiquitous reed canary grass and other invasives,” said Kris Stenshoel, EWEB’s vegetation management coordinator.

“By plugging, planting and seeding around newly exposed soil that appeared as the water level dropped, we are able to colonize the area with native plant species,” he said, adding that he’s seen a greater diversity of animals make use of the area.

Federal regulators will inspect the pond this month and make a decision on the final water level. If they approve of the current pond elevation, EWEB will cease pumping, and the water level will remain high during the wet months and drop about 12 inches during the summer – much like a natural wetland, according to utility spokesman Joe Harwood.

Image: Photo Courtesy EWEB. Workers have been busy conducting reseeding at the Walterville Pond.