Sewerage financial system for Lake Biwa environmental conservation

Author(s): Naoko Hirayama
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Institution or organization of origin: The University of Shiga Prefecture
Country: Japan


The sewerage systems can play a very important role in reducing pollution loads from households and other point sources of pollution for lake environmental conservation. The Ministry of Land, Infrastructure, Transport and Tourism (MLITT) categorizes the sewerage system broadly into two groups, one being the “Public Sewerage System (PSS)” and another being the “Regional Sewerage System (RSS)”. In the Lake Biwa case of Shiga Prefecture, the wastewater from commercial establishments, public buildings, small industries and general households has been one of the major sources of lake pollution. There are 39 sewerage enterprises in 19 municipalities in the Lake Biwa basin. The earliest suppling started was the Otsu City PSS in 1969, eight businesses started in 1982, and the development progressed from 1986 to 2000. About the finance of the sewerage system, sewerage costs are divided into “capital costs” such as construction costs and “maintenance costs”. Although 40% is covered by the user fee, in reality, the user fee alone cannot cover it, and many local governments transfer it from the general account. In Shiga prefecture, as for the coverage rate by the user fee out of the overall incurred costs for managing the sewerage system by each of the municipalities, the rate is less than 50% for 60% of sewerage enterprises. The sewerage systems have to be economically possible. It is necessary to carefully consider the finances for future sewage treatment, taking into account the decrease in revenue water and the prospect of usage income.

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