University of Victoria Aquifer Stress Evaluation

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Published by the Ministry of Environment and Climate Change Strategy - Water Protection and Sustainability
Licensed under Access Only

The scope of this project is to derive aquifer-scale estimates of annual volumes for groundwater withdrawal, recharge, and groundwater’s contribution to environmental flows as a means to provide screening level estimates of aquifer-scale stress using the groundwater footprint. The groundwater footprint (GF) is calculated for unconfined aquifers from aquifer-scale, steady-state estimates. For more information see:

Forstner, T., Gleeson, T., Borrett, L., Allen, D.M., Wei, M., and Baye, A. 2018. Mapping aquifer stress, groundwater recharge, groundwater use, and the contribution of groundwater to environmental flows for unconfined aquifers across British Columbia. Water Science Series, WSS2018-04. Prov. B.C., Victoria B.C.

Data and Resources

Additional Information

Purpose

The BC Aquifer Stress evaluation is a decision-support level analysis rather than decision-making level analysis. Screening-level values are provided to assist water managers in understanding relative levels of aquifer stress and identifying areas where detailed scientific assessments are needed.

Data Quality

Major limitations include:

  • The analysis is aquifer scale, which can mask local-scale groundwater stress.
  • The analysis is steady state (not varying with time), which cannot include long-term trends, seasonal variation or drought impacts.
  • Subsurface flow between aquifers is not considered.
  • The methods have not been applied to confined aquifers or aquifers where results suggest E > R (due to uncertainty to input parameters). Assessing aquifer stress in these aquifers requires additional studies.
  • The input parameters, described below, are uncertain and not based on local-scale data.
Lineage Statement

Withdrawal (W) is estimated based on national, provincial,and municipal scale statistical data, generally following previous methods and then distributed to individual aquifers. Withdrawal is considered a conservative over-estimate that will be replaced by licensed or reported groundwater volumes as this information becomes available. Recharge (R) is estimated from

  1. a simple water balance model, HELP , that has been previously used in BC as well as
  2. a global hydrologic model, PCR-GLOBWB . HELP modeling used characteristic climatic conditions, hydrogeological properties and water table depths for each aquifer.

These estimates are considered suitable for province wide aquifer scale recharge estimation but do not account for local variations in hydrology, geology or topography, neglects three-dimensional processes and time-varying properties. The global hydrologic model includes MODFLOW, has a 10 km grid resolution and is calibrated to global streamflow data and compared to BC streamflow data, but does not use local data.
Groundwater contribution to environmental flow needs (E) is estimated from PCR-GLOBWB results using two methods:

  1. modeled baseflow and the groundwater presumptive standard and
  2. modeled streamflow and the BC EFN policy.

The first method appropriately uses hydrogeologic processes such as groundwater discharge as baseflow, but not explicitly consistent with the BC EFN policy . The second method is consistent with the BC EFN policy but does not consider hydrogeologic processes.

More Information

Contact Information

NameChristine Bieber (businessExpert)
Emailchristine.bieber@gov.bc.ca
OrganizationMinistry of Environment and Climate Change Strategy
Sub-OrganizationWater Protection and Sustainability
NameAndarge Baye (businessExpert)
Emailandarge.baye@gov.bc.ca
OrganizationMinistry of Environment and Climate Change Strategy
Sub-OrganizationWater Protection and Sustainability

Access & Security

Who can view this dataset? Public
Who can download this dataset?Public

Metadata Information

Record Published 2018-09-10
Record Last Modified 2018-09-10
Resource Status completed

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