Groundwater potentiometric-surface contours and well numbers used to map groundwater potentiometric-surface altitude in 2022 and groundwater-level changes between 1968, 1991, and 2022 in the alluvial aquifer in the Big Lost River Valley, south-central Idaho

Groundwater potentiometric-surface contours for spring 2022 (April 4 to 8, 2022) and autumn 2022 (October 30 to November 4, 2022) were created for the alluvial aquifer in Big Lost River Valley. The well numbers and station names used to create the potentiometric-surface contours and groundwater-level change maps are provided in this data release. The location, depth to water, and potentiometric-surface altitude for these wells can be accessed on USGS National Water Information System (NWIS) or Idaho Department of Water Resources (IDWR) groundwater portal. The interpreted 20-foot contours of the potentiometric-surface are also provided in this data release. The contours are referenced to the North American Vertical Datum of 1988 (NAVD 88). The potentiometric-surface contours are divided into three water-bearing units - shallow, intermediate, and deep - based on well depth, potentiometric-surface altitude, and hydrogeologic unit. The intermediate and deep units were only identified in the southern portion of the valley near Arco, Idaho. The potentiometric-surface contours ranged from 4,900 to 6,660 feet above NAVD 88. The groundwater-level change at well sites from spring to autumn 2022, spring to autumn 1968, spring 1968 to spring 2022, spring 1991 to spring 2022, and spring 1968 to spring 1991 were calculated and are provided in a shapefile.

本数据集针对大洛斯特河谷（Big Lost River Valley）的冲积含水层（alluvial aquifer），生成了2022年春季（2022年4月4日至8日）与2022年秋季（2022年10月30日至11月4日）的地下水测压水面等值线。本次数据发布中提供了用于绘制该测压水面等值线与地下水位变化图的监测井井号及测站名称。上述监测井的位置、地下水埋深及测压水面高程，可通过美国地质调查局（USGS）国家水信息系统（National Water Information System, NWIS）或爱达荷州水资源部（Idaho Department of Water Resources, IDWR）的地下水门户网站查询获取。本次数据发布同时提供了经解译的20英尺间隔测压水面等值线数据，该等值线以1988北美垂直基准面（North American Vertical Datum of 1988, NAVD 88）为垂直基准。根据监测井深度、测压水面高程及水文地质单元，本次生成的测压水面等值线被划分为浅层、中层与深层三类含水单元，其中中层与深层含水单元仅在爱达荷州阿科（Arco）附近的河谷南部区域被识别。本次生成的测压水面等值线的高程范围为相对于NAVD 88的4900至6660英尺。本次数据发布还计算并提供了多个时段内各监测井点位的地下水位变化数据，包括2022年春季至秋季、1968年春季至秋季、1968年春季至2022年春季、1991年春季至2022年春季以及1968年春季至1991年春季，相关成果以形状文件（shapefile）格式存储。