| Title | Hydraulic tomography analysis of municipal well operation sata with geology-based groundwater models at the Mannheim Wellfield in Kitchener, Ontario, Canada |
| Download | Download (whole publication) |
| |
| Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
| Author | Tong, X; Illman, W A; Berg, S J; Luo, N |
| Source | Regional-Scale Groundwater Geoscience in Southern Ontario: An Ontario Geological Survey, Geological Survey of Canada, and Conservation Ontario Geoscientists Open House; by Russell, H A J ; Ford, D; Holysh, S; Priebe, E H; Geological Survey of Canada, Open File 8528,
2019 p. 28, https://doi.org/10.4095/313602  Open
Access |
| Year | 2019 |
| Alt Series | Ontario Geological Survey, Open File Report 6349 |
| Publisher | Natural Resources Canada |
| Publisher | Government of Ontario |
| Meeting | Regional-Scale Groundwater Geoscience in Southern Ontario: Open House; Guelph; CA; February 27-28, 2019 |
| Document | open file |
| Lang. | English |
| Media | on-line; digital |
| Related | This publication is contained in Regional-Scale Groundwater
Geoscience in Southern Ontario: An Ontario Geological Survey, Geological Survey of Canada, and Conservation Ontario Geoscientists Open House |
| File format | pdf |
| Province | Ontario |
| NTS | 40P/08 |
| Area | Southern Ontario; Kitchener |
| Lat/Long WENS | -80.5000 -80.0000 43.5000 43.2500 |
| Subjects | hydrogeology; mathematical and computational geology; groundwater; aquifers; groundwater resources; resource management; water wells; models; hydraulic analyses; hydraulic conductivity; groundwater
levels; groundwater flow; geostatistics; modelling; Mannheim Wellfield; HydroGeoSphere; Methodology |
| Released | 2019 02 08 |
| Abstract | The sustainable management of groundwater resources is essential to municipalities worldwide due to the increasing water demand from dramatic population growth. Planning for the optimized use of
groundwater resources requires a sound understanding of hydrogeology and reliable estimation of hydraulic parameters such as hydraulic conductivity (K) and specific storage (Ss). Traditionally, K estimates are obtained through the application of
empirical formulae to representative grain sizes, laboratory analysis of core samples, slug/bail tests and pumping tests. Reliable estimates of Ss are difficult to obtain and are typically obtained through the analysis of pumping tests. The
interpretation of pumping tests with analytical solutions with various simplifying assumptions has become the de facto standard in the consulting industry; however, research has shown that in non-idealized real-world applications, biased K and Ss
estimates may be obtained which can lead to poor predictions of independent stress events. Thus, there is a critical need for more robust methods to estimate hydraulic parameters.
A new approach using hydraulic tomography (HT) to estimate K and Ss
has been applied at the Mannheim East wellfield in Kitchener, Ontario. In particular, four different geological models with homogeneous geological layers are calibrated by coupling HydroGeoSphere (HGS) (Aquanty, 2018) and the parameter estimation
code PEST (Doherty, 2005) using water-level variation records in observation wells collected during municipal well operations. The four geological models are well calibrated and yield reliable estimates that are consistent with previously estimated
values for the shallower layers where most data points are collected. However, K and Ss estimates for deeper layers with fewer observation points vary more significantly among the models. The comparison of simulated and observed draw down for both
model calibration and validation reveals that all four groundwater flow models with varying geology can capture the water-level fluctuation pattern quite well. However, rapid water-level variations at some wells are not captured very well, which
could be due to the presence of high K pathways and heterogeneity not captured by these geological models. Currently, we are developing a HT approach based on geostatistics to handle this issue for both unconsolidated and fractured geologic
media.
Overall, our research reveals that: 1) the HT analysis of municipal well records is feasible and yields reliable K and Ss estimates of individual geological units where drawdown records are available; 2) these estimates are obtained at the
scale of its intended use of municipal well operations, unlike small-scale estimates typically obtained; 3) characterization and estimation can be conducted using existing data, thus removing the need for dedicated pumping tests which leads to
substantial cost savings; and 4) data collected during municipal well operations can be used for parameter estimation and groundwater modeling, thus they are critical and should be archived. |
| Summary | (Plain Language Summary, not published)
Volume of abstracts for Ontario Geological Survey and Geological Survey of Canada groundwater geoscience Open house with Conservation Ontario. |
| GEOSCAN ID | 313602 |
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