Maryland and Delaware - Climate Response - Water Table Wells
Groundwater levels for the monthly water conditions include a combination of real-time continuous (2 of the 26 wells) and discrete or hand-held (24 of the 26 wells) water levels. Discrete measurements include one measurement during the month and the date is indicated on the hydrograph. For the real-time wells, discrete measurements were used up until June 2010. From July 2010 onward, the last data entry of the month is used for the water summary calculations.
Criteria for selecting a groundwater site for assessing climatic conditions:
- Located in an unconfined (water-table) aquifer;
- Open to a single, known hydrogeologic unit/aquifer;
- Groundwater hydrograph reflects changes in climatic conditions;
- No indicated nearby pumpage and likely to remain uninfluenced by pumpage, regulated streamflow or changes related to human activities;
- Minimum period of record is 10 years of continuous/monthly records;
- Minimally affected by irrigation, canals, drains, pipelines, and other potential sources of artificial recharge;
- Well has casing--dug wells not used;
- Water levels show no apparent hydrologic connection to nearby streams;
- Well has never gone dry; and
- Long-term accessibility likely.