Conducted in locations across the Americas, the paper “Too Many Streams and Not Enough Time or Money? Analytical Depletion Functions for Streamflow Depletion Estimates” synthesizes results from extensive experiments around the effectiveness of analytical depletion functions for estimating the streamflow depletion that results from pumping groundwater. For many people there’s…


Forest disturbance has significant effects on B.C. ecosystems that last for decades. The effects of forest disturbance are cumulative over space and time, and have implications for ecological functions, hydrological responses, and public safety. These facts serve as evidence for the importance of equivalent clearcut area (ECA), a unit of…


Where it all Began.

Foundry Spatial began operations in 2009 as a consulting practice. Come 2012, however, the idea of collecting data, analyzing it, and providing clients PDFs and some data files that would quickly become out of date didn’t seem like the most efficient way to build a business and deliver value. Instead…


This 2020 study, Comparing Streamflow Depletion Estimation Approaches in a Heavily Stressed, Conjunctively Managed Aquifer, offers a comparison of analytical depletion functions (ADFs) against a validated numerical model created for estimating streamflow depletion. This numerical model was developed as part of an interstate compact, and as such had substantially greater effort put into its development and calibration compared to models used for comparison studies elsewhere. Authors Samuel C. Zipper, Tom Gleeson, Qiang Li, and Ben Kerr conducted the study in the highly stressed aquifer of the Republican River (Colorado/Kansas, USA) with funding from NSERC, Kansas Geological Survey, the University of Victoria, and Foundry Spatial. Overall, the ADF produced comparable results to the validated numerical model at a fraction of the cost and time.


With funding from the Province of BC, NSERC, UVic, and Foundry Spatial, this 2020 study, Streamflow depletion from groundwater pumping in contrasting hydrogeological landscapes: Evaluation and sensitivity of a new management tool, provides the first comparison of analytical depletion functions (ADFs) against calibrated numerical models. Conducted in various hydrologic settings…


In this 2019 study, Cannabis and residential groundwater pumping impacts on streamflow and ecosystems in Northern California, authors Samuel C Zipper, Jennifer K Carah, Christopher Dillis, Tom Gleeson, Ben Kerr, Melissa M Rohde, Jeanette K Howard, and Julie K H Zimmerman demonstrate the application of analytical depletion functions for evaluating impacts of groundwater pumping from different water uses.

This study was made possible with funding from the Natural Sciences and Engineering Resources Council of Canada, SD Bechtel, Jr. Foundation, University of Victoria, The Nature Conservancy — California, and Foundry Spatial. With their help, authors quantified the impact of an emerging agricultural frontier, Cannabis cultivation, on water resources, using the Navarro River (Coastal Range) in Northern California as a case study.


Conducted in 2019 at the Navarro River (Coastal Range) in Northern California, the Rapid and Accurate Estimates of Streamflow Depletion Caused by Groundwater Pumping Using Analytical Depletion Functions study tested 50 combinations of analytical depletion functions against an ‘archetypal’ numerical model.

Overall, authors Samuel C. Zipper, Tom Gleeson, Ben Kerr, Jeanette K. Howard, Melissa M. Rohde, Jennifer Carah, and Julie Zimmerman found that the performance of analytical depletion functions was comparable to archetypal numerical models. With the help of funding from the Natural Sciences and Engineering Resources Council of Canada, S.D. Bechtel, Jr. Foundation, University of Victoria, The Nature Conservancy — California, and Foundry Spatial, researchers also identified that the new approach works best in flatter terrain, with wells close to streams.


Published in May 2018, this study, Groundwater Pumping Impacts on Real Stream Networks: Testing the Performance of Simple Management Tools, defined three components of the analytical model approach: analytical model, apportionment method, and area of influence. Funded by the Government of Canada (NSERC) and the University of Victoria, this study provides the first test against numerical models using the groundwater flow system around Nanaimo on Vancouver Island, B.C. as the exemplar.

Overall, authors Samuel C. Zipper, Tom Dallemange, Tom Gleeson, Thomas C. Boerman and Andreas Hartmann identified the significance of stream geometry and drainage network for calculating estimates.


This 2018 study, Streamflow Depletion Modeling: Methods for an Adaptable and Conjunctive Water Management Decision Support Tool, was the initial investigation into the viability of bringing the impacts on streamflow from pumping groundwater into web-based decision support tools. Conducted in British Columbia’s Central Interior in the Bulkley Valley, the study acts as a proof of concept for analysis and decision-support.

With funding from the Government of Canada (NSERC), the University of Victoria, and Foundry Spatial, this study tested analytical models and methods for estimating depletion on real-world stream networks. Authors Xander Huggins, Tom Gleeson, Hailey Eckstrand, and Ben Kerr provide the first response to the question: “can we incorporate groundwater impacts on surface water in our water technology framework?”


The California Overdraft Crisis

California currently extracts about 14.2 million acre-feet of groundwater every year, and about 80% of Californians rely on groundwater for their daily needs. Long seen as a safe and reliable source of water, resilient to drought and scarcity, California now finds itself in an extreme water crisis with frightening environmental…

Foundry Spatial

Empowering decisions to shape the future of watersheds and aquifers.

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