Lakes and High Water Conditions Frequently Asked Questions
5/17/2008 - The Carolinas are currently experiencing extreme drought conditions that have greatly reduced lake levels in the Catawba-Wateree lake system. While most of the information on this page primarily pertains to high-water issues, some information presented below is valid at any time.- What does "full pond" mean?
- What does “crested” mean?
- How are lake levels measured?
- What does “moving water” mean?
- Why are some lakes above full pond while others are below?
- Weren't the lakes and dams built for flood control?
- How often are the dams inspected for safety?
- Why can’t you just lower the lake level at my lake to prevent flooding later?
- Why can’t you lower all the lakes prior to rainfall?
- How does Duke Energy communicate to the public about high water?
- How do I go about replacing my dock that was damaged by high water?
- What do I do if I see docks or other large debris floating in the lake?
- Will Duke Energy reimburse me for property that was damaged or lost because of high water levels?
- Will Duke Energy disconnect power to those in lower lying areas once flooded?
- Does Duke Energy have a flood easement along the Catawba lakes?
- Why can't you predict how high the lakes will be based on the forecast?
- Hurricane predictions are made in days and sometime weeks in advance of the storm reaching the Duke Energy service area. Can't Duke Energy lower the reservoirs to a level that would hold the rain we receive?
Q. What does "full pond" mean?
A. Full pond means that the lake is full or at mean sea level elevation (msl) for that particular lake. This level is measured at the hydro station dam. Levels upstream of the dam will be higher due to topography and elevation. For example: Lake Norman is at 760 msl which is equal to 100.0. If the lake level is said to be 101.0 then it is at 761 msl or one foot above full pond.
Q. What does “crested” mean?
A. Crested means that the lake level has reached its peak for that particular event.
Q. How are lake levels measured?
A. Lake levels are measured on the lake side of hydrostation dams.
Q. What does “moving water” mean?
A. Duke Energy moves water by every means available to lower lake levels on the Catawba River system without creating any additional damage. This includes moving water through our hydro generating units, over open spillways or by opening designated floodgates - or a combination of these methods.
Q. Why are some lakes above full pond while others are below?
A. In an event such as flooding we experienced after Hurricane Frances, more water can be moved over the spillway than we can move through generating units -- with minimal impact downstream.
Q. Weren't the lakes and dams built for flood control?
A. Although they do help lessen the impact of heavy rainfall and run-off, the dams along the Catawba River were not built for flood control. They were built for the production of electricity and have limited ability to mitigate the effects of large quantities of storm water.
Q. How often are the dams inspected for safety?
A. Duke Energy dams are safe and inspected daily by hydro station personnel (more often after heavy rainfall), routinely by Duke Energy personnel, annually by the Federal Energy Regulatory Commission, and every five years by an independent engineering consultant.
Q. Why can’t you just lower the lake level at my lake to prevent flooding later?
A. The Catawba River chain of lakes is operated as a system. What is done on one lake impacts the next. Therefore, Duke Energy moves water through the system at the benefit of the whole basin - not individual lakes.
Q. Why can’t you lower all the lakes prior to rainfall?
A. Lakes James and Norman comprise about 80% of the storage capacity of the Catawba-Wateree. Over 90% of this storage is above Lake Wateree. The other smaller lakes have no storage capacity and could fill up in just a small amount of time. Our objective is to make as much storage room as possible in areas we can.
Q. Why are some lakes above full pond while others are below?
A. In an event such as flooding we experienced after Hurricane Frances, more water can be moved over the spillway than we can move through generating units -- with minimal impact downstream.
Q. Why can’t you just lower the lake level at my lake to prevent flooding later?
A. The Catawba River chain of lakes is operated as a system. What is done on one lake impacts the next. Therefore, Duke Energy moves water through the system at the benefit of the whole basin - not individual lakes.
Q. Why can’t you lower all the lakes prior to rainfall?
A. Lakes James and Norman comprise about 80% of the storage capacity of the Catawba-Wateree. Over 90% of this storage is above Lake Wateree. The other smaller lakes have no storage capacity and could fill up in just a small amount of time. Our objective is to make as much storage room as possible in areas we can.
Q. How does Duke Energy communicate to the public about high water?
A. Duke Energy uses a variety of communications vehicles including the local media and phone calls to local emergency management and local volunteer fire departments depending on the needs of the particular area.
The primary means for the public to get existing and projected lake levels during high water conditions are Duke Energy's web site - www.duke-energy.com and the toll free Lake Neighbor Information Line (1-800-829-5253). In addition, there are call trees to identified groups that share this information broadly.
Q. How do I go about replacing my dock that was damaged by high water?
A. All parties desiring to reconstruct a dock or other facilities due to weather damage must receive written authorization from Duke Energy's Lake Management prior to beginning the activity/construction within the project boundary of a Duke Energy lake. Fees will be waived for facilities damaged by high water that are built as previously approved and that comply with the current guidelines. Any expansion of the previously approved facility will require an application including fees. Applicants have six months from the day of the event to request to reconstruct the facility as a result of weather damage.
Q. What do I do if I see docks or other large debris floating in the lake?
A. Duke Energy encourages your assistance with debris that may become navigational hazards (large trees, docks, etc.). If you if are in a position where you can safely secure the debris (i.e., tie to dock or a tree), please do so and call Duke Energy at 1-800-443-5193. Please leave your name and a phone number where we can reach you along with as much detail as you can provide regarding the location of the debris.
Q. Will Duke Energy reimburse me for property that was damaged or lost because of high water levels?
A. Unfortunately, Duke Energy cannot take responsibility for losses that occur as a result of an act of nature. As with all natural disasters, losses caused by severe weather are typically handled through an individual's insurance company.
Q. Will Duke Energy disconnect power to those in lower lying areas once flooded?
A. To ensure public safety, local officials may ask Duke Energy to disconnect electric power to those neighborhoods affected by flooding. Duke Energy will attempt to notify customers in advance of disconnecting power, if possible. We will continue to monitor conditions and re-connect power for these customers when local officials indicate that it is safe to do so. We appreciate our customers’ patience and cooperation during this time. (In some cases, disconnections are made to prevent damage to electrical equipment.)
Q. Does Duke Energy have a flood easement along the Catawba lakes?
A. Yes, generally Duke Energy has a ten foot flood easement. This is ten feet above full pond (vertical feet).
Q. Why can't you predict how high the lakes will be based on the forecast?
A. We can predict which lakes will get above full pond but until it begins to rain and we see the impacts on stream gages and inflows to the river - we can't predict how high the levels will reach.
Q. Hurricane predictions are made in days and sometime weeks in advance of the storm reaching the Duke Energy service area. Can't Duke Energy lower the reservoirs to a level that would hold the rain we receive?
A. In preparing for high water events, Duke Energy must consider many other factors in determining the movement of water out of the system so that the impact is minimized. In the early stages of preparation these factors include but are not limited to the following: (Note: as the storm track changes, so will some of these considerations)
- Public impact and property damage.
- Operational constraints of power plants - maintain the ability to continue to operate the steam plants associated with individual lakes (Marshall, McGuire, Riverbend, etc.)
- Water supply intake levels for municipalities and their customers.
- Environmental impacts of significant lowering of lakes.
Our preparation in advance of storms, and our river management, allows Duke Energy to reduce river and lake flooding.
