Fracture flow

A significant portion of groundwater exists within open fractures in bedrock aquifers. These aquifers tend to be much more complex than the basin-fill or alluvial aquifers where the groundwater exists in pore spaces between clasts. Some fractured aquifers have a high enough degree of fracturing that they will have flow characteristics that are very similar to unconsolidated sedimentary aquifers due to the high percentage of open fracture space. However, most fractured bedrock aquifers, have limited fracturing intensity and direction that creates an anisotropic groundwater flow regime. Groundwater modeling of anisotropic fractured bedrock aquifers requires additional data to determine preferential flow direction and potential limiting factors for groundwater flow in the aquifer. GGI conducts geologic mapping and detailed fracture analyses to determine dominant fracture orientations controlling groundwater movement. In addition, we conduct long-term (96 hour to 14-day) pumping tests on water wells and monitors observation points to determine groundwater flow characteristics. These data can then be used to create a groundwater model of the subject area that accurately represents the real world system.

Selected Projects

1. Red River Pass Water Availability
2. Rancho San Lucas Water Availability

Spring emerging from fractures bedding planes in a fractured sedimentary bedrock aquifer

Red River Pass model grid for stream connected fractured bed rock aquifer