Ground Water Level and Land Subsidence in Ishikari Bay Area, Hokkaido, Japan

The main purpose of these observations is to monitor the effects of usage of groundwater so that bad effects on the underground water and the land (such as subsidence) are avoided. In the north region of Sapporo City - Ishikari, an underground water level of unconfined and confined aquifers, and ground subsidence of two confining beds have been measured by eleven observation stations trough 1992. Observations started in February 1966. Measurement data is composed of daily and monthly averages for ground water and subsidence levels, and is recorded in pamphlets, using tables and graphs.