4 - Well Field Exploration - 2024

January 9, 2024 - City Engineer Bob Veenstra reviewed the process of well field exploration.  A resolution was passed approving engineering agreement with Veenstra & Kimm to develop and oversee a Well Field Exploration Program (engineering and geotechnical services) in an amount not to exceed $30,000.

December, 2023 - Since the early 1980s, the City of Dallas Center has conducted a series of well field exploration programs.  The purpose of a well field exploration program is to identify one or two sites where the City could construct a new shallow well.  With the construction of Well No. 11, the City utilized the last preferred site identified in the 2014 Well Field Exploration program.

Based on the age of the existing wells, it would not appear the City would need to replace any of the existing wells prior to 2030. However, with the ongoing drought conditions, the City should be prepared to construct an additional well should the capacity of one or more of the existing wells decline due to the ongoing dry weather conditions. 

The primary reason a well field exploration program is necessary is the variability of the alluvial sand and gravel aquifer along the Raccoon River Valley. As evidenced by previous well field exploration programs, the thickness of the sand and gravel formation in some areas is greater than 40-feet.  In areas not more than a few hundred feet away, there is literally no sand and gravel formation.  The location of the thicker sand and gravel formations cannot be readily ascertained from the ground surface.  The preferred locations for future wells can only be determined by the information collected from well field exploration programs and information from the existing wells.

The goal of the well field exploration program is to allow the City to construct a future well at the best possible location. The goal of the well field exploration program would be to identify sites the City could utilize for a future well. Well Field Exploration program does not necessitate the City constructing a well. Rather, the well field exploration program is viewed as preparedness in the event a well becomes necessary.  By knowing the location of the next well, the City can more quickly move through the design and construction phase if conditions require the City construct an additional or replacement well.