MUNICIPAL IMPACTS

Municipal Impacts

  The municipal impacts of removing the dams along the Lower Snake River would be minimal.  Within a 20-mile wide strip centered along the river from the mouth to the state line a total 14 cities would be impacted, including Lewiston, Idaho. The major cities impacted are Burbank, Asotin, Clarkston in Washington, and Lewiston, Idaho.  The total population of the towns that have public water distribution systems is 36,500.  The anticipated affect that would occur if the dams were removed is the potential lowering of the water table.  It is expected that with the river continually flowing, the water would not infiltrate into the ground water at levels currently experienced.  This effect was noticed back in the late 60s and 70s when the dams were first completed, as water table increased in the area.  The effect that lowering the water table would have for these municipalities is potential modifications to the water wells and increased pumping cost of the water.  The potential modifications to the wells would be to extend the well and lower the pumping apparatus deeper into the well.  These improvements would only be necessary of the current wells are not low enough to screen an adequate amount of water.  Estimates of the lowering of the water table are about 50 feet caused by the removal of the dams.  This does not include the effects that would be realized if the population significantly increased.  The cost of this modification is about $10,000 per well.  There are 14 municipal wells in the area.  Assuming that 70% of the wells would require modification (this is a very conservative estimate) then 10 wells would be modified at a cost of $100,000.  The other modification that would be realized is increased pumping because of the lower water table.  The pumping of the well system would increase just to make up for the lowering of the water level.  Assuming an average day use of 100 gallons per day per person, 90% efficiency the transfer of power, and a 50-foot lowering of the water table, then the average increase cost of pumping would be about 80 cents per person per year at electricity cost of $.10 per kilowatt-hour.  This would amount to a small financial impact for removing the dams.