Water Quality Determination And Evaluation Of Jin Wei Lake In BaoJi

Man-made lake has many functions such as improving city ecological environment, regulating range microclimate,strengthening the hydrology adjustment ability,and providing recreation,traveling and so on for people.A long-term water quality monitoring,analyzing and evaluating has been done to Jin Wei Lake of Baoji—a man-made lake,to investigate factors which affecting the water quality in the lake,and to put.forward methods for pollution control and operational guidance.The conclusions are as follows:(1)Monitoring results shows that:Besides TKN,monitoring values of other target basically achieve IV kind water quality of《Surface water environment quality standard(GB3838-2002)》,monitoring value of DO achieves I kind of water quality, besides the individual spot,monitoring value of TP achievesⅢkind of water quality, monitoring value of TKN exceeds relative seriously,the maximum monitor value is 3.36mg/L,exceeds 1.68 times(compare with V kind of water quality).(2)Using method of comprehensive weighting to evaluate water quality,results shows that:water quality of Jin Wei Lake changes between IV kind and exceedingⅤkind.Man-made lake is a closing water substance of poor liquidity,opposite to reservoir and river,it is easy to pollute,and it has small area,small water environmental capacity and poor ability self-purification of water body,so it is very easy to change its water quality by external factors.(3)Factors such as time of water cumulation,water coming from upper reaches,raining,substrate sludge and so on has been discussed.The pollutant density will increases with time of water cumulation;affects of water coming from upper reaches is mainly decided to water quality;when raining,because of the poor water quality of rainwater,lake water will be polluted;during water cumulation,bottom of the Jin Wei Lake has silted up much silt,and the pollutant in substrate sludge will release in the lake again,causes secondary pollution to lake.(4)Aimed to the water quality condition and all kinds of pollution factor of Jin Wei Lake,corresponding control measures has been proposed.Such as:reasonably controls the movement of sluice gate,strengthens the control and management of water quality monitor to branch and the discharge outlet of peripheral pollution source,takes some.corresponding measure like vegetation control or percolation to control the surface runoff and CSO pollution,reduces silting up of substrate sludge as far as possible,so that secondary pollution to lake can be reduced.