Prineville Wellhead Protection Pilot

Contact Information

Project Manager:	David Anderson
Phone:	541-633-2012
E-mail:	David Anderson, Hydrogeologist

Site Summary

DEQ is working to enhance the existing geologic and hydrogeologic conceptual framework in Central Oregon. The pilot will allow the City of Prineville to fully evaluate, develop, and plan for current and future drinking water resources. It would also enable DEQ to improve its overall management and decision-making within a critical groundwater area with regard to potential contamination sites, for drinking water based assessments of critical groundwater areas, and evaluation of the significance underground injection control (UIC) wells in the area. As part of this pilot, DEQ is developing a more robust hydrogeologic conceptual model for the Prineville sub-basin, developing a numerical groundwater flow model for the sub-basin, and looking to enhance the delineation of wellhead protection areas (WHPAs) of city and public water supply systems.

Phase 1 activities were completed in June 2009 and Phase 2 activities were completed in June 2011. 

Phase 1 activities included:

• Gathering and obtaining existing datasets from several state agencies and from individual DEQ sites;
• Development of a conceptual geologic and hydrogeologic model using existing data to establish the framework for groundwater flow in the Prineville sub-basin;
• Forming partnerships with City of Prineville, Crook County, private property owners, other DEQ programs, and state, federal, and local agencies (e.g., Oregon Health Division, Oregon Department of Geology and Mineral Industries, United States Geological Survey, and Bureau of Land Management) for the pilot;
• Modifying and creating geographic information system (GIS) base data layers and a database system for the pilot, including existing land use, stream, well, cleanup site and other coverages;
• Construction of a rough numerical model, GIS, and database for future development and refinement of the model and provide a visual reference point for the pilot. Deliverables included a GIS-based model, database, figures, and establishment of a web site for dissemination of information; and
• Accompanying GIS layers and databases to be used for future work in the area and as a prototype for additional enhancement of critical drinking water areas at other locations in Oregon.

Phase 2 activities included:

• Collection and incorporation of new data into the current conceptual geologic and hydrogeologic site model (CSM) which is used to evaluate groundwater flow in the Prineville sub-basin;
• Continued construction of a working numerical groundwater model, GIS, and database for current and future management in the development and refinement of the area's groundwater resources; and
• Continued work with the City of Prineville, Oregon Water Resources Department (WRD), Oregon Health Division (OHD), and other agencies, to help DEQ in the management of critical groundwater resources and decision-making with regard to potential contamination sites.

Reports

Phase 2

• Final Groundwater Model
• Tables 1-8
• Figures (click here to dowload all figures)
• Figure 1 - Project Study Area
• Figure 2 - Cross Section Location Map
• Figure 3a - Cross Section A-A'
• Figure 3b - Cross Section B-B'
• Figure 3c - Cross Section C-C'
• Figure 3d - Cross Section D-D'
• Figure 3e - Cross Section E-E'
• Figure 3f - Cross Section F-F'
• Figure 3g - Cross Section G-G'
• Figure 4 - Ancestral Channel Locations
• Figure 5 - Top of Basement Unit Contour Map
• Figure 6 - Top of QTs3 Unit Contour Map
• Figure 7 - Top of QTs2 Unit Contour Map
• Figure 8 - Land Surface Contour Map
• Figure 9 - Thickness of QTs3 Unit
• Figure 10 - Thickness of QTs2 Unit
• Figure 11 - Aquifer Permeability Plateau Area
• Figure 12 - Model Grid
• Figure 13 - Conceptual Model Layers
• Figure 14 - General Groundwater Flow Contours
• Figure 15 - Simulated vs Observed Water Levels Summer Model
• Figure 16 - Simulated vs Observed Water Levels Winter Model

Phase 1

• Preliminary Groundwater Model
• Figures (Click here to download all figures)
• Figure 1 - Model Boundary Map
• Figure 2 - Cross Section Location Map
• Figure 3a - Cross Section A-A'
• Figure 3b - Cross Section B-B'
• Figure 3c - Cross Section C-C'
• Figure 3d - Cross Section D-D'
• Figure 3e - Cross Section E-E'
• Figure 3f - Cross Section F-F'
• Figure 3g - Cross Section G-G'
• Figure 4 - Ancestral Channel Locations
• Figure 5 - Top of Basement Unit Contour Map
• Figure 6 - Top of QTs3 Contour Map
• Figure 7 - Top QTs2 Contour Map
• Figure 8 - Land Surface Contour Map
• Figure 9 - Thickness of QTs3
• Figure 10 - Thickness of QTs2
• Figure 11 - Conceptual Model Layers

[print version]