日本是个水资源比较缺乏的国家,目前全国水资源利用率已达到20%左右,新辟水源所需的投入越来越大。为此,日本政府除了采取开源措施和提高水的利用率、鼓励全社会利用循环水外,还十分重视对雨水的利用。早在1980年,日本建设省就开始推行雨水贮留渗透计划。采用雨水贮留渗透计划,可以有效地补充涵养地下水,复活泉水,恢复河川基流,改善环境生态条件。利用雨水贮留渗透的场所一般为公园、绿地、庭院、停车场、建筑物、运动场和道路等。采用的渗透设施有渗透池、渗透管、渗透井、透水性铺盖、浸透侧沟、调节池和绿地等。 Japan is a country that lacks water resources. At present, the utilization rate of water resources in the country has reached about 20%, and the investment required for the development of new water resources is getting bigger and bigger. To this end, apart from taking measures to increase revenue and improve water utilization, the Japanese government encourages the whole society to make use of recycled water and attaches great importance to the utilization of rainwater. As early as 1980, Japan’s Ministry of Construction began to promote rainwater retention infiltration plan. The rainwater retention and infiltration plan can effectively supplement and conserve groundwater, revive spring water, restore river base flow and improve environmental and ecological conditions. The use of rainwater storage and infiltration sites are generally parks, green spaces, courtyards, parking lots, buildings, playgrounds and roads. The infiltration facilities used are infiltration tank, permeate pipe, permeate well, permeable cover, drench ditch, regulating pool and green space.