New Asian Carp Deterrent: Sound, Bubbles and Light

By KBJR News 1

Water samples from the St. Croix River have tested positive for genetic material from silver carp, suggesting the invasive, leaping Asian species may be present in the river as far north as the dam at St. Croix Falls, according to the Minnesota Department of Natural Resources.

January 3, 2013 Updated Jan 3, 2013 at 4:17 PM CDT

St. Paul, MN (NNCNOW.com) --- The Minnesota Department of Natural Resources is hoping a new deterrent will stop the invasion of Asian Carp in the the state's waterways.

In a report released today, the DNR has concluded that an Asian Carp barrier using sound, bubbles and lights is the most viable option to deter the invasive fish from moving past the Lock and Dam #1 in Minneapolis.

The chief advantage of a lock barrier is that it does not need to block fish passage across the entire river, but to deflect fish away from the smaller opening at the lock.

The goal is to prevent the fish from using the lock chamber to gain access to the upper reaches of the river, which connects to other rivers and lakes.

While an electric barrier inserted into the water would be the most effective technology for carp deterrence, the report concluded it is not a feasible option due to significant public safety risks and corrosion to metal components of the lock.

The estimated construction cost for such a system is $12 million, though due to uncertainties in the final design and construction, the cost could be as high as $19 million. The estimated annual operation and maintenance cost is up to $250,000.

The Minnesota Legislature approved a $7.5 million appropriation from the Outdoor Heritage Fund to design and construct Asian carp barriers, of which $5.6 million is allocated to design and construct the barrier at Lock & Dam #1.

Of that amount, DNR anticipates needing about $1 million for the design, leaving $4.6 million for construction.

Based on the range of cost estimates and schedule, an additional $8 million to $15 million will be needed to complete the barrier and operate it through the next biennium.

Asian carp have been found in Minnesota waters of the Mississippi River, but there is no evidence yet that they are reproducing here. The DNR is concerned about the voracious-eating fish moving upstream beyond the Twin Cities to lakes and smaller rivers.

The fish are capable of eating 5 to 20 percent of their body weight each day. Asian carp feed on algae and other microscopic organisms, often outcompeting for food with native fish.

Posted to the web by Krista Burns