Improvement and Application to Dilution Ratio Calculating Method

In order to make the traditional dilution ratio more scientifically and reasonably, the ratio of the admitting water contamination concentration to the concentration guide of III level water (RACG), the ratio of the sewage discharge contamination concentration to the concentration guide of III level water (RSDG) , and the harm coefficient are introduced to improve the traditional dilution ratio. Then, taking Dong liao River as demonstration, the new dilution ratio was tested. The results indicates that the new dilution ratio not only can be considered as the eco-environment water evaluation index and get the calculation results be consistent with the results got by Wang xi-qin (2006), but also can measure quantitatively the water resources functional capacity surplus and water resources functional capacity deficit of the river. The new dilution ratio can be applied to the studies of water quality evaluation, calculating the region water resources sustainable capacity, the sustainable development of region, and so on.