Pipestone MN - Well Field Optimization and Well Performance Evaluation

LRE Water was retained by the City of Pipestone, Minnesota (City) to conduct a well-field optimization and well performance evaluation (Evaluation). The objective of this Evaluation was to review existing data including historical water levels, specific capacity data, and pumping test data, and provide graphical representation and evaluation of the data that could be used to track well performance and minimize well interference currently and in the future. The Evaluation provided information and guidance for managing the City’s well and well-field data, and specifically for optimizing the operation of the wells and well field to maximize long-term capacity. These can be achieved by adopting sound well and well-field management practices.

 

WELL FIELD OPTIMIZATION AND WELL PERFORMANCE EVALUATION

After reviewing the available specific capacity data for each well, well performance trends over time were not able to be established for several reasons.  The available specific capacity test data were not completed at the same pumping rate and for the same duration; which is critical since specific capacity decreases with time and higher pumping rates.  Further, the wells were not allowed to return to static conditions prior to commencing the specific capacity tests.  Lastly, data were not available for other wells in the area that may have been pumping and causing well interference on the City wells during their specific capacity tests. Because of these limitations, the temporal trends of specific capacity data for each well are inconclusive and were not good indicators of when well rehabilitation should occur.  LRE provided recommendations to removed these data limitations to ensure accurate well field optimization and well performance analysis in the future.