Topeka State officials are warning that Kansas reservoirs and lakes are quickly filling with sediment, which could lead to severe water shortages.
“Certainly in the lives of our children and grandchildren, this is one of the more significant issues that the Legislature will have to get our hands around,” said state Rep. Tom Sloan, R-Lawrence.
Sloan, chairman of the newly formed Vision 2020 Committee, has been conducting hearings on the issue.
The amount of money necessary to address the problem of reservoirs filling with sediment is staggering, and the consequences of letting it go unattended are unacceptable, officials say. Alarms are being sounded, as state officials face a current budget crisis because of the national recession.
“These numbers get very big and scary in a hurry,” said Earl Lewis, assistant director of the Kansas Water Office. “We have ignored a growing problem over the past 50 years.”
Officials say the state needs to take action now because of the sometimes decades-long lead time needed to plan and build new reservoirs.
“How long do we really have to take care of this problem — that may well be dependent on the occurrence of a major drought,” said Ed Martinko, state biologist and director of the Kansas Biological Survey. “But time is running out, and we have to make some decisions that have long-term consequences on the future of Kansas.”
At stake is a $6 billion investment in the reservoirs that provide drinking water to two-thirds of Kansans, including those in nearly all of eastern Kansas. In addition, the reservoirs are used for flood control and recreation.
The highest areas of sedimentation are in eastern Kansas.
Since 1974, Lake Perry has lost 18 percent of its capacity to 92 million cubic yards of sediment. Six lakes have lost more than 20 percent of their capacity, including Fall River, Tuttle Creek, Kanopolis, Toronto and John Redmond Reservoir, which has lost approximately 45 percent of its capacity.
The culprit is runoff and bank erosion.
Natural lakes last for thousands of years. But man-made reservoirs, such as the ones in Kansas, have short life expectancies: 50 years to 100 years. The 93 reservoirs in Kansas used for drinking water have an average age of 51 years, according to the Kansas Water Office.
“Many of our reservoirs are silting in much faster than anticipated, than their designed life,” Martinko said.
This sedimentation results in greater costs to treat water for drinking, reduced recreational capabilities, and the prospect that certain watersheds could be facing shortages in the near future.
Ed Carney, with the Kansas Department of Health and Environment Bureau of Environmental Field Services, said there are things that can be done to address the problem, such as dredging, building secondary dams and constructing new reservoirs.
Of the current reservoirs, he said, “That’s too big an investment, I would think, to walk away from.”
But the options are expensive.
Building a new dam the size of Clinton Lake’s would easily cost $500 million, Lewis said. Simply to keep up with maintenance of the current dams, the state needs $75 million, he added.
A legislator asked Lewis whether that would be for just one year.
Lewis answered that it would take $75 million every year “forever.”