Measuring of the stratification in the Latian dam reservoir

Water stratification occurs when water masses with different properties – salinity, oxygenation, density, temperature – form layers that act as barriers to water mixing. The boundary between the warmer and cold waters is called the thermocline. Lake stratification is the separation of lakes into three layers:

  1. Epilimnion- top of the lake.
  2. Metalimnion (or thermocline) – middle layer that may change depth throughout the day.
  3. Hypolimnion- the bottom layer.

The thermal stratification of lakes refers to a change in the temperature at different depths in the lake, and is due to the change in water’s density with temperature. Natural resource and environmental managers are often challenged by problems caused by lake and pond thermal stratification. Fish die-offs have been directly associated with thermal gradients, stagnation, and ice cover. Excessive growth of plankton may limit the recreational use of lakes and the commercial use of lake water. With severe thermal stratification in a lake, the quality of drinking water also can be adversely affected. One commonly used tool to reduce the severity of these lake management problems is to eliminate or lesson thermal stratification through aeration. Tehran Regional water authority hired BAB to provide a solution for measuring the temperature and salinity in different layers of the Latian Lake. This Dam is a dam located less than 25km from Tehran in the south of city of Lavasan. It is one of the main sources of water for Tehran metropolitan region. For this project BAB used one of the world most practical and ragged systems names DST designed by Star-Oddi.

DST CTD is the smallest salinity logger on the market that measures and records salinity (conductivity), temperature and depth. Recorded data is stored in the logger‘s internal memory with a real-time clock reference for each measurement. The DST CTD is supported by the SeaStar software and the communication Box which serves as an interface between the logger and a PC. Communication between the logger and the Communication Box is wireless. a plastic protective housing  has been used  under harsh environmental conditions and for mounting to deployment lines or moorings.