都市域の水資源として地下水が再評価されつつある。その地下水涵養の手法として,雨水浸透施設による雨天時排水の浸透が期待されている。そこで,本研究では,雨水浸透施設が設置されて以来19年以上経過した地域での雨天時流出挙動を,浸透施設の貯留能力と浸透能力を計算するサブモデルが組み込まれた分布型モデルを用いることで表現し,降雨特性ごとに各浸透施設からの浸透量を算出し,類型化した。その結果,浸透施設の機能を考慮しなかった場合と比較して,浸透施設の機能を考慮した場合の下水管渠への流出量は1/3まで削減されるという顕著な流出抑制効果があることが明らかとなった。浸透施設のなかでもとくに,浸透LU側溝からの浸透量が大きいことが定量的に示された。降雨特性ごとに,下水管渠への流出量および浸透量を評価したところ,降雨特性によらず,大降雨時でも浸透施設が雨水浸透に寄与することが明らかとなった。設置以来19年経過後においても,雨水浸透施設は大降雨時の流出抑制だけではなく,地下水涵養の観点からもきわめて有効に寄与していることが定量的に評価された。 Groundwater is being re-evaluated as water resources in urban areas. As a method of groundwater recharge, and infiltration of wastewater during wet weather is expected by rainwater infiltration facilities. In this study, we use a distributed model sub-model to calculate the penetration capability and storage capacity of infiltration facilities have been built, the behavior of runoff when it rains in the region that are older than 19 years since have been established facilities rainwater infiltration expressed by, and then calculate the amount of infiltration of rainfall for each characteristic from each infiltration facilities, and typology. As a result a significant inhibitory effect on runoff, runoff to sewer compared to the case as if you did not consider the functions of infiltration facilities, and consider the functions of infiltration facilities would be reduced to 1/3 became clear that there is. In particular, the amount of penetration from the ditch is greater penetration LU has been shown to quantitatively Among the infiltration facilities. Where the rainfall for each characteristic, we evaluated the amount of runoff and infiltration to the sewer, that regardless of the characteristics of rainfall, infiltration facilities will contribute to the infiltration of rain water, even when large rainfall was revealed. Even after 19 years since installation, rainwater infiltration facilities can not only suppress rainfall runoff when large, have contributed very effectively from the standpoint of groundwater recharge has been evaluated quantitatively.
