by John Gates
Osoyoos Lake Water Quality Society has been testing lake water quality since 1993, the results from which are forwarded to the BC MoE (now ENV) for their database. Water testing in 2017 follows a procedure established with MoE in earlier years, and is captured in this relatively short Powerpoint presentation. Testing time frames are dependent on spring run-off as well as weather and other environmental factors.
Tests were carried out at five lake locations weekly from early July to late September using the OLWQS purpose built pontoon boat. Measured parameters are dissolved oxygen, temperature, specific conductivity, and pH at various depths, and secchi depth.
Data is presented as tables and charts for ENV, the OLWQS website, and presentation. OLWQS observes the data and compares it with the objectives set by ENV for secchi depth and dissolved oxygen.
Of particular interest are the thermoclines and the dissolved oxygen declines in the lake that narrow the pathway for fish sensitive to water that is either too warm (>17C) or has too little oxygen (<4 mg/l).