Water Quality Test Report1

Janaury to March 2005
(Collaborative program between FRC/PSMC-PLEACB)

Introduction

The main objective of water quality monitoring programs is to improve conservation management of Phewa Lake (particularly water quality) by enabling local communities and institutions for letting take initiatives on environmental awareness, capacity building and conservation programs. In connection with this, Phewa Lake Environment Awareness and Capacity building Project of Pokhara Sub-Metropolitan City (PLEACBP-PSMC) and Fisheries research Center, Pokhara signed a Minute of Understanding (MOU) on 1st March 2005 in order to evaluate water qualities and assist in promoting awareness program for the benefit of target group. Although the MOU was signed in March a detailed water quality-monitoring program have been prepared and implemented since January 2005.

General overview of limnological condition and its effect

It is acclaimed that eutrophication of water resources of Phewa lake is a serious problem. Different water quality parameters were monitored in past showed the lake is currently characterized by high nutrient level due to high rate of material discharge and as the flooded terrestrial vegetation decays. The decomposition of these large quantities of organic matter in the water produces inorganic nutrients such as ammonia, nitrate and phosphorus. This increased productivity caused by excessive organic loads resulting in decline in water quality; and these symptoms of overproduction are called eutophication. Water hyacinth tends to flourish under such eutrophic conditions.

The eutrophication process of lakes is characterized by increased nutrient concentration, more specifically phosphorous condition, due to input, for example, of human sweage or fertilizer run-off from agricultural areas. The eutrophication process leads to considerable changes in the structure of the lake ecosystem, which in turn reduces the possibilities of using the lake for recreation, fishing, and other uses of lake water. Eutrophication process, with respect to Phewa Lake, is in increasing trend as evidenced by past limnological studies. For example, Jones et al. (1989) described the lake as obligoeutrophic while after a decade the lake was characterized as meso-eutrophic (FRC,1999). Such an increased trend of eutrophication of water resources of Phewa Lake has been believed to be caused by several catastrophic activities which includes, intensive agricultural practices in catchments area, municipal swerage disposal, excessive siltation due to deforestation and agronomic practices, and unhealthy water use by urban people (use of phosphorous containing detergent for washing clothes, disposing house garbage directly in the lake).

The project PSMC/PLEACBP in partnerships with Fisheries Research Center, Pokhara has undertaken water quality monitoring program in order to evaluate water qualities monitoring program in order to evaluate water qualities, assist in promoting environmental awareness program and capacity building of local people on Phewa lake conservation for the benefit of target group. The water quality monitoring of Phewa Lake was started from January 2005 and the monitoring scheme followed was as described in project proposal.