I have written a couple of blog entries now concerning the two small recreational parks that are located close to Forsyth Missouri in southwest Missouri. In what has now turned out to be a wetter than normal year, both of these areas are once again submerged beneath the waves.
The reason has been a much wetter than normal year for precipitation. The chart here shows the thirty year average rainfall per month in Springfield Missouri with the actual, so far, for 2009. Some of this excess water has ended up in one of three area reservoirs; Beaver Lake, Table Rock Lake or Bull Shoals each of which is serviced by a dam to regulate the flow. The amount of water they can hold is really tremendous in scope. Beaver Lake covers over 3000 acres while Table Rock and Bull Shoals are 43,000 and 45,000 respectively. Each dam measures the water level based on the mean sea level and each has a level it strives to maintain. The absolute level that none of these dams can be allowed to go over is termed the ‘top flood pool’ which is the level above which water must be released to prevent the flooding of nearby properties. In the case of Table Rock dam, when the reservoir is above the maximum flood pool, excess water goes over the auxiliary overflow spillway at the north end of the dam.
In normal times with average rainfall, each is maintained at some level well below this top flood mark. For Beaver dam the average over the last five years has been 1115.7 feet msl (mean sea level), while Table Rock and Bull Shoals are 911.1 and 652.0 feet respectively. Keeping water at the ‘correct or desired’ levels is a bit of a balancing act that is dependant on rainfall, the season and conditions that might be in effect downstream. The Core of Engineers and other authorities do a fantastic job 99% of the time and are stymied only when we experience years that fall outside what would be considered normal. That was the case this year and as a result, we have bodies of water behind each dam that are exceptionally high. So high, in fact that this area would be ill prepared if we getting large amounts of rain anytime in the next quarter of year or so. As of this writing, the current levels of the three dams are as follows:
Beaver 1128.81 feet msl or 13.11 feet over the five year average
Table Rock 915.52 feet msl or 4.42 feet over the five year average
Bull Shoals 679.57 feet msl or 27.57 feet over the five year average
Each dam has been releasing water as fast as is prudent but right now, with so much that is needed to be drawn down form the two dams upstream, the Bull Shoals Lake are will no doubt get even more flooded in the weeks to come, this assuming we get little or no more rain.