PITTSBURGH – The Pennsylvania Department of Environmental Protection has issued permits to four companies for commercial sand and gravel dredging on portions of a 100-mile stretch of the Allegheny and Ohio rivers.
According to Regional Director Charles A. Duritsa, the permits include special restrictions to protect aquatic life and groundwater supplies.
“We built in additional protections to dredging permits to prevent any immediate impact on threatened and endangered aquatic life and public drinking water supplies,” Duritsa said.
“In addition, we are working on a new computer model to help us determine dredging’s future impact on water supply wells. Until the model is done, we have broad dredging restrictions in place for areas near a public water supply.”
The permits allow Glacial Sand and Gravel, Hanson Aggregates (formerly Pioneer Mid-Atlantic), Tri-State River Products, and The Lane Construction Co. to dredge in approved areas from the state line on the Ohio River up to Lock and Dam No. 9 on the Allegheny River.
“These companies can dredge only in areas where diving surveys have been conducted or where dredging was conducted in the last five years,” Duritsa said. “If they want to dredge in a new area covered under this permit, they must first conduct all of the proper surveys to ensure that no threatened or endangered aquatic life would be impacted.”
The companies must conduct comprehensive mussel surveys in any new area they plan to dredge, prior to requesting approval to dredge in those areas. If the surveys show significant freshwater mussel populations, those areas will be excluded from dredging.
If threatened or endangered species are found, dredging is prohibited.
The protocol to conduct these surveys was revised based on input from mussel experts from the Army Corps of Engineers.
The approved dredging areas avoid groundwater-well capture zones for a number of public drinking water supplies; areas identified by the Pennsylvania Fish and Boat Commission as areas where fish species of special concern are found; and locations having significant freshwater mussel resources or where threatened or endangered mussel species exist.
Fish species of special concern include the endangered silver chub and black bullhead; the threatened small mouth buffalo and mooneye; and the river redhorse, a candidate for protection.
Dredging continues to be prohibited in areas around dams, islands, bridge piers, pipelines, public water supply surface water intakes, shallow-shoreline areas and in Allegheny River Pool 6 near Kittanning. Additional restrictions have been placed on dredging in Allegheny River Pool 8 because of the Northern riffleshell mussel, a federally endangered species found there.
The permits are valid for five years. The previous permits had expired. Dredgers have operated on the rivers in and around Pittsburgh for the more than 100 years.