Tradable Discharge Permit System for Water Pollution: Case of the Upper Nanpan River of China

A discharge permit system for water pollution of theupper Nanpan River has been tested since 1992. Thispaper proposed the shift of the current non-tradablepermits to tradable permits to attain the samepollution reduction targets at a lower cost. It wasfound that this river appeared good for trading. Apilot trading program for point sources was thenrecommended to a smaller trading zone. There would beten potential trades for chemical oxygen demanddischarge, gaining an annual cost-saving of ChineseYuan 2.4 million, or saving 18.4% of the total annualcost to attain the reduction target without trading.The marginal pollution reduction cost was estimated atChinese Yuan 959 for one kilogram chemical oxygendemand per day. Meanwhile, `without trading' and `withtrading' scenarios would bring about 900.9 kg/day and51.5 kg/day of redundant reduction respectively. Thenet annual benefit arising from trading, about ChineseYuan 1.6 million, would still be significant. At last,the study recommended that compliance monitoring andexecuting institution requirements be kept in mindwhile designing the program. An information systemneeds to be established to provide potentialparticipants relevant information. The method ofpermit allocation and lifespan of permits should alsobe addressed later.