Information page for lakes

Lake Water Level Assessment

Each lake in the Dobson Ranch chain of lakes has a normal water level for which weekly measurements are made at specific locations; see tabulation below. These measurements are then compared to their normal values and posted. A zero value would mean the water level, at the time of the measurement, was at the normal water level for that lake. Positive values would indicate higher than normal water levels while negative values would indicate a less than normal water level.

The graph posted on the website shows the water levels of the individual lakes against their normal values. The elevation of the water in Lakes 1, 2 & 3 (the first three lakes are directly connected) is higher than the elevation of the water in Lake 4 and is the same from Lake 4 on down to Lake 8. The normal water level is taken to be the water level when the water is just at the edge of the lake end standbox ready to spill over into the next lower Lake.

The plot thus shows how each lake differs from its normal water level, not how each lake compares to the next.

The usual setup for the lakes is to have each lake slightly higher than a normal water level allowing water to flow downstream to maintain a positive water level in each lake.

A positive water level is not always achieved. The main cause for the fluctuations is the daily variation in weather conditions. On some days the evaporation is high; a function sunshine, wind and air temperature. To gain water, the water draw from the SRP canal can be increased to add more water to the lake system. There is, however, no outlet for the water taken into the lake. Water cannot be drained from the lakes if there is too much water. The SRP draw can be curtailed or stopped, but only evaporation and seepage will cause the water levels to drop. In some instances the water levels in the lakes is allowed to drop below their normal water levels in anticipation of rain, such as during the monsoon season. During the annual SRP dry-up the water level will fall several feet until the end of the dry-up and flow is re-established; beginning in November and lasting into March.