Published: December 09, 2008 07:29 pm      

Lake level, boat ramps could be victims of drought

Going below 678 feet could cause problems into next tourism season

Unless there is significant rainfall this month in the Upper Cumberland River Basin the lingering drought may drop the level of Lake Cumberland low enough to put several popular boat-launching ramps out of the water.

“We hope to hold the level where it is now through December,” said Tom Hale, operations manager for the U.S. Army Corps of Engineers in Eastern Kentucky. He said the problem may develop after the first of the year and could extend into next summer’s tourist season.

“It’s the drought. It has absolutely nothing to do with work at the dam,” said Hale. However, Allison Jarrett, public affairs specialist with the Corps, said the situation is compounded by the existing low lake level necessitated by rehabilitation of Wolf Creek Dam.

On a more positive note, Jarrett remarked: “I wouldn’t predict that the lake level will be lower next summer,” noting the possibility of a rainy winter and spring.

Lake Cumberland on Tuesday was 679.62 feet above sea level, about a third of a foot below the target level of 680 feet. The lake has been about 43 feet below normal since January 2007 to ease pressure on seepage-plagued Wolf Creek Dam. Work is under way to install a concrete barrier wall through the earthen section of the dam and deep into the bedrock below the dam.

Hale said if the lake goes below 678 feet –– 1.62 feet below the current level –– “we will be looking at closing (ramps) or posting notices (of possible launching difficulties).” Hale said the Corps already has signs ready to post.

If the drought continues into next summer and the lake level is forced lower, Hale said the Corps “ ... would look at extending some ramps.”

Jarrett emphasized that every effort is being made to keep the lake level at 680 feet. She concedes, however, that if the drought lingers through the winter, the lake level is likely to go down. The Corps is not predicting how low the lake might get “ ... because we don’t know,” Hale said.

An approaching low-pressure system with potential to drop between 2 and 3 inches of rain in the Cumberland River Basin wouldn’t have an immediate effect on the lake level, according to Jarrett. “Runoff raises the lake level, not the amount of rainfall,” Jarrett pointed out. She noted that exceedingly low water tables due to two years of drought cause the ground to absorb rainfall, limiting runoff.

Lake Cumberland has been awfully low a couple of times during its 58-year history. The all-time low level was 673.01 feet on January 1, 1954, following a severe drought. The level dropped to 677.80 on February 9, 1977 during work to correct a serious leak discovered during the late 1960s. The lowest the lake has been during the current work at the dam is 678.61 at 9 a.m. October 22.

Jarrett said none of the water-intake systems on Lake Cumberland is in jeopardy because cities using water out of the lake have extended intake pipes, mostly to the 650 level.

Optimism is clouded by a Corps news release with a somber tone. It says the Cumberland River system appears headed for lake levels at some projects that have not been observed since 1956. If the Cumberland River Basin does not receive signif-icant rainfall runoff by the end of the year the system could be faced with some very difficult operational decisions regarding river and lake levels.

Extremely dry weather conditions coupled with lake level drawdowns ass-ociated with ongoing repair work at Wolf Creek and Center Hill dams have resulted in low lake levels at several area lakes. Lake Cumberland, impounded by Wolf Creek Dam; Dale Hollow Lake, and Center Hill Lake are the projects most affected by the low water conditions, the Corps said.

Corps of Engineers water managers are operating the Cumberland River Basin reservoir system in accordance with the interim operating plan developed prior to the onset of construction work at Wolf Creek Dam. At the same time, the lake level restrictions set for Wolf Creek Dam and Center Hill Dam have severely reduced the volume of water available to Corps of Engineers water manag-ers, the news released pointed out.

“We started out the summer season with only about one-fourth the nor-mal volume of water in the reservoir system. This limitation is far more ext-reme than any drought that we have experienced since the reservoir system was completed,” reveal-ed Bob Sneed, who oversees water manage-ment activities for the Cumberland River Basin projects.

The Cumberland reservoir system is designed to store a large volume of cold water in the late winter and spring and then release that water from storage during the summer and fall when natural stream flows will not meet the water demands placed on the system.

“In 2007 and 2008 we have operated the system according to the priorities established in the interim operating plan,” Sneed said. The system priorities detailed in the plan are 1) water supply, 2) water quality, 3) navigation, 4) hydropower, and 5) recreation. The reservoir system continues to be available for flood damage reduction operations as needed, he noted.

Corps of Engineers water managers continue to work closely with representatives from federal, state, and local agencies, and various water users to reduce or eliminate the impacts from this limited supply of water in order to conserve and stretch resources. The basic approach has been to route the minimum volume of water through the reservoir system needed to maintain an uninterrupted water supply to water intakes, avoid serious environ-mental consequences, and keep commercial navig-ation traffic moving. Hydropower production and certain forms of recreation have been the areas most impacted by this operational plan, the news release said.

Dry conditions through-out the Cumberland Basin this summer and fall have meant lake levels in the large tributary projects have continued to fall.

The lake level at Dale Hollow is now at elevation 634.3. This is approximately 0.7 feet lower than it was on this date one year ago. The current lake level is the lowest it has been since November 1983 when it reached elevation 632.8. The record low lake level for Dale Hollow of 631.1 was observed in January 1956. Current projections, based on no significant rainfall, call for the Dale Hollow elevation to continue to fall to around elevation 633 by the end of the year.

Water flowing through the main-stem navigation projects -- Cordell Hull, Old Hickory, Cheatham, and Barkley -- along the Cumberland River will continue to be very low, but lake levels at these projects are not expected to fall to critical levels, the Corps’ news release said.

Lake visitors are being asked to use caution and be aware there may be unmarked structures underwater that could damage vessels. Visitors should also be mindful of wakes, tie-ups and prop washout when launching or near the bank. These courtesies will help ensure that current conditions do not add to the problem of shoreline erosion, the Corps said.

At each of the affected lakes, boaters planning to use ramps located within marina lease areas are encouraged to contact that marina to obtain the stat-us of individual ramps. Corps of Engineers ramps may be used at the boater’s discretion, but during this period of low water, it is best to always check the condition of the ramp prior to launching.