Pandin Lake is located in Barangay San Lorenzo in San Pablo City. It has an area of 240,000 sq. m. (24 hectares) and a maximum depth of 61.75 meters.

As of 2007, only 5,825 sq. m. (0.58 hectare) is occupied by aquaculture structures (3 %).

Water Quality Monitoring Program

The Laguna Lake Development Authority (LLDA), by virtue of RA 4850, as amended, has the primary responsibility to promote the development of the Laguna de Bay region, while providing for environmental management and control, preservation of the quality of life and ecological systems, and the prevention of undue ecological disturbance, deterioration and pollution.

The LLDA has been conducting regular water quality monitoring with the following objectives:

• To accurately assess the suitability of the lake for all its present and intended beneficial uses;

• To evaluate the impacts of development activities on the lake’s waterquality that will serve as important criteria for environmental planning and management; and

• To provide sound technical basis for water resources management policies and programs for the lake.

Routine monitoring programs conducted by LLDA include the Laguna de Bay and its tributaries as well as the Seven Lakes of San Pablo City and Tadlac Lake in Los Banos.

One water quality monitoring station was established for Pandin lake. During the conduct of the sampling activity, water temperature and dissolved oxygen concentration are measured at the surface and at 2,3,4,5,6,10,15,20, 25,30 and 35 meters depth. A gallon of composite water from surface to 5-meter depth is also collected for chemical analysis. The chemical parameters analyzed at the laboratory include pH, total suspended solids (TSS), total dissolved solids (TDS), turbidity, chloride, nitrate, ammonia, inorganic phosphate, biochemical oxygen demand (BOD) and chemical oxygen demand (COD). Zooplankton sample is collected by passing five pails of surface lakewater through a 35-micron meshsized plankton net. Zooplankton sample is preserved in a 10% formalin solution. On the other hand, phytoplankton sample is taken from a gallon of composite sample, placed in small plastic container and preserved with Lugol’s solution. Water transparency is likewise measured and all the physical observations including weather condition are noted and recorded.

At present, monitoring is conducted during the first (January, February, March) and last quarters (October, November and December) and in June and September.