Despite study, One Lake hurts sturgeon, turtlesBy ANDREW WHITEHURST,
Recent newspaper articles about the Biological Opinion from the U.S. Fish and Wildlife Service (USFWS) on the effects of the One Lake project would have readers believe that the document exonerates the Rankin-Hinds Flood Control and Drainage District (levee board) for the damage that their dredging and damming project would do to two threatened species (one turtle, one fish) found in the Pearl River. The USFWS Biological Opinion doesn’t absolve the levee board of the project’s damage to the river. To the contrary, page 14 of the document’s “hydrology” section has the following statement:
“Overall the Pearl River Basin has undergone alterations due to changes in the landscape (e.g. land clearing, navigation, flood control) that impact the ecological functions of the area. These ongoing impacts have led to the reduction and/or loss of habitat which has resulted in the listing of species under the Endangered Species Act.”
In other words, the reason the levee board and the USFWS must protect these species has everything to do with the accumulated impacts to the Pearl River from earlier alterations to the river’s hydrology and habitats. The creation of the Ross Barnett Reservoir in 1963 was the largest single disruption to the Pearl, as all major dams are, but the lower river also has sills that block it, for the now decommissioned Pearl River navigation canal below Bogalusa. The levee board’s lake project will add to the historic damage.
What the Biological Opinion provides is an estimated “body count” of the proportions of the existing populations of the ringed sawback turtle and gulf sturgeon that will be affected by the One Lake project. The project will displace an estimated 20 sturgeon. Dredging the channel and removing streamside trees and vegetation will displace or kill an estimated 1,306 turtles in the 10 miles of the river in the project’s footprint.
In both cases, these numbers represent less than five percent of either animal’s estimated population. That is judged by the USFWS as not enough to place either species in jeopardy of becoming extinct.
A fish passage canal or sluice around the lake’s low head dam is proposed as a way to allow adult sturgeon to migrate and utilize any spawning habitat they may have been restricted from using in the urban section of the Pearl River.
The creation of managed, protected sand islands in the 1,900-acre lake itself is proposed as a way to give any remaining turtles in the dredged section the habitat they need for digging nests, basking and feeding. Also, 10 miles of protected riverbanks will be purchased outside the project area in other Pearl River reaches to give the turtle’s additional habitat.
How unarmored sand islands will persist in this dredged lake is anybody’s guess in a section of river 500-2,000 feet wide receiving flow velocities of four to six feet per second during large spillway releases. Policing the islands and riverbanks will be required by some law enforcement agency. The islands must also be kept free of invasive tree and plant species, which would cover the sandbars the turtles require to nest. Nobody can say if any of this will work to accommodate these animals’ needs, so expensive long-term monitoring of these will be required.
Overall, the lake dredging alternative is still the most environmentally-disruptive plan and remains quite unpopular outside of Rankin and Hinds counties. Fourteen government entities downstream in both Mississippi and Louisiana oppose it, including the combined Louisiana House and Senate. A levees-only plan that expanded the floodplain on the Rankin County side of the Pearl is also feasible and would not disrupt the habitats to the same degree as dredging a lake into the river’s channel.
The overall question is why the most environmentally-damaging alternative for flood control should be chosen for a river that already has so many impacts and disruptions. The Pearl River needs restoration in many ways, but dredging and impounding it further cannot, by any stretch of the imagination, be considered restoration.
Andrew Whitehurst is Water Program Director for Healthy Gulf, a non-profit environmental group. He has a masters degree in Wildlife Ecology from