The Idaho Conservation League welcomes news that the Idaho Department of Water Resources has rejected two commercial dredge mining proposals that would have threatened Red River, near Elk City in north-central Idaho.

Red River is an important tributary that forms the headwaters of the South Fork Clearwater River. Red River provides habitat for Chinook salmon, steelhead, bull trout, Pacific lamprey, westslope cutthroat trout and other sensitive and threatened fisheries.

The miners proposed using suction dredges for up to four months per year in areas where extensive salmon spawning has been documented. In fact, taxpayers have funded restoration in Red River to the tune of millions of dollars over the past 10+ years to repair damage caused by overgrazing and historic dredge mining.

Comments from the Idaho Department of Fish and Game, Nez Perce Tribe, NOAA-Fisheries, ICL and others emphasized the importance of Red River, and asserted that dredge mining in these areas would adversely affect sensitive habitat, and could undermine tribal treaty rights as well as harm culturally and spiritually significant areas.

What Else Is Happening With Dredging?

The rejection of the Red River mining proposal comes on the heels of an abbreviated public comment period on rules governing dredge mining downstream, in the South Fork Clearwater River. There, the Idaho Department of Water Resources, working with the U.S. Forest Service, Bureau of Land Management, Environmental Protection Agency and others, allows limited dredge mining during a one-month season, under controlled conditions.

Despite the fact that the mining season opened on July 15, the IDWR made several last-minute changes to the rules on July 10. While the revisions resulted in some minor changes to the IDWR rules, other requirements from the Forest Service and BLM ensure protections of threatened and endangered fisheries. Hundreds of comments were submitted from Idahoans who advocated for protection of clean water and habitat. Those comments made a difference.  

The most significant change dealt with refilling holes left after dredge mining. Prior IDWR rules required existing holes to be filled before excavating a new hole. The IDWR made a change that requires miners to only refill holes at the end of the dredge season. Despite the change at the state level, though, federal rules still require holes to be filled prior to excavating new ones, rendering the IDWR change moot.

In the Salmon River, the Idaho Department of Lands offered a 10-year riverbed mineral lease to a Riggins-based miner who has proposed a commercial dredge mining operation, despite the fact that he has not applied for or received the required federal permits. After a two year-long review, IDL submitted a lease to the applicant in May 2017, but as yet he hasn’t signed it. IDL has indicated that he has until mid-August to do so. Even with a lease in hand, additional federal permits are required, otherwise the miner could face Clean Water Act violation penalties of up to $51,570 per day.

In other areas of the state, under the EPA’s general permit for small-scale mining, some dredge mining can occur outside of endangered species habitat and other sensitive areas.

What is Suction Dredge Mining, Anyway?

Imagine a high-powered vacuum floating on pontoons. The miner dives to the bottom of the stream and sucks up gravel and sediment with a large hose, excavating down to the bedrock. The dredged material (sediment, gravels, rock and water) is discharged through a sluice box on the back of the floating dredge, capturing the gold, and spewing the sediment and gravel back into the water. Piles of discharged sediment can restrict the flow of rivers, change hydrology and leave unstable  holes that can persist in the streambed.

The practice can wreak havoc on fish habitat and stream water quality:

  • Sediment discharged by the dredges can smother fish eggs, affect overall fish health and further threaten endangered and sensitive fish species.
  • Gravel deposited behind the dredges can create unstable spawning beds, which can be attractive to fish yet fail to provide the stable substrate the eggs need to survive.
  • Holes created by dredging can persist, altering river flow, leading to downstream erosion and creating dangerous wading conditions for boaters and anglers.
  • Mercury, embedded in the gravels and river sediment,  can be released into the water column, threatening public health, aquatic species and downstream users.
  • Fisheries biologists, hydrologists and others agree that the impact from suction dredge mining is harmful to fish and threatens water quality. That’s why restrictions, limitations or statewide bans have been put in place in Idaho, Oregon, California, and other western states.
  • Dredges can harm stream banks and streamside vegetation as the equipment is hauled in and out of the water or used to dredge beneath the banks.