Conceptual and numerical groundwater flow model of the Cedar River alluvial aquifer system with simulation of drought stress on groundwater availability near Cedar Rapids, Iowa, for 2011 through 2013

Abstract

assisted with the collection, processing, and analysis of geological, hydrogeological, and geophysical data. Additionally, Kyle Davis provided insightful guidance for approaches to groundwater model construction.

One Ranney Well Can Make a Difference: The Impacts of a Radial Collector Well on Groundwater Level and Quality in the Cedar River Alluvial Aquifer

“…Boyd (1998) used deuterium and sulfate tracers as evidence of a strong connection between the SEM10 production well and the Cedar River. Groundwater flow models (Schulmeyer 1995; Schulmeyer and Schnoebelen 1998; Turco and Buchmiller 2004; Haj et al 2021) were used and estimated that most water pumped from SEM10 originated from storage in the aquifer (49%) and the Cedar River (46%). During this study, pumping rates from RCW5 were up to 10 times greater than previously observed in nearby vertical production well SEM10, and SC and water temperature data from SEM10 and RCW5 indicated that much of the water pumped from RCW5 was likely induced recharge from the Cedar River.…”

“…Collected data and results from this study can be used to design additional, tailored stress tests of the aquifer to better understand and quantify the interactions of the RCWs and the Cedar River. Data and results will also be used in additional calibration of an existing groundwater flow model for simulating the interactions of the RCWs, the Cedar River, and the aquifer to improve forecasting the effects of pumping from RCWs on the quantity and quality of groundwater during drought or low-flow conditions (Haj et al 2021).…”

“…The aquifer near the Seminole wellfield is generally composed of 42‐72 feet (ft) of sand and gravel and eolian sand deposits (Schulmeyer and Schnoebelen 1998; Iowa Department of Natural Resources 1998a). Although the aquifer is considered hydraulically connected to the underlying Silurian, carbonate bedrock (Iowa Department of Natural Resources 1998b; Turco and Buchmiller 2004; Iowa Geological and Water Survey 2010; Gannon et al 2011; Haj et al 2021), the connection may be limited due to the presence of shale at the bedrock contact (Boyd 1998; Johnson et al 2020; Kalkhoff 2021). During low flows in the Cedar River, vertical and horizontal groundwater flows in the aquifer near areas unaffected by municipal pumping are toward the river channel (Squillace 1996).…”

“…During high flows, flow directions near the channel are reversed and water from the Cedar River infiltrates the aquifer. Flow direction may also be reversed near production wells (Schulmeyer and Schnoebelen 1998; Haj et al 2021). Production wells in the Seminole wellfield were screened in sand and gravel overlying the bedrock surface (Schulmeyer and Schnoebelen 1998; Turco and Buchmiller 2004; Haj et al 2021).…”

“…Flow direction may also be reversed near production wells (Schulmeyer and Schnoebelen 1998; Haj et al 2021). Production wells in the Seminole wellfield were screened in sand and gravel overlying the bedrock surface (Schulmeyer and Schnoebelen 1998; Turco and Buchmiller 2004; Haj et al 2021). The mean pumping rates from vertical wells range from 0.97 to 1.42 MGD (Turco and Buchmiller 2004), and pumping from a RCW ranges from 3.0 to 11.0 MGD (Ha and Haj 2021; Haj et al 2021).…”