Palouse Ground Water Basin Framework Project Final Report Prepared by: 121 S. Jackson St. Moscow, ID 83843 Web Site: www.terragraphics.com And Ralston Hydrologic Services 1122 E. B St. Moscow, ID 83843 January 31, 2011 Palouse Ground Water Basin Framework Project FINAL report ii Palouse Ground Water Basin Framework Project Final Report Prepared for: 1300 NE Henley Ct., #6 Pullman, WA 99163 Grant G1000293 between the Washington Department of Ecology and the Palouse Conservation District Prepared by: TerraGraphics Environmental Engineering, Inc. 121 S. Jackson St. Moscow, ID 83843 www.terragraphics.com and Ralston Hydrologic Services 1122 E. B St. Moscow, ID 83843 January 31, 2011 Palouse Ground Water Basin Framework Project FINAL report Table of Contents Executive Summary..................................................................................................................... xiv Section 1.0 Introduction ................................................................................................................. 1 1.1 Purpose and Objectives......................................................................................................... 1 Section 2.0 Task 2 – Compilation .................................................................................................. 5 2.1 Collection.............................................................................................................................. 5 2.1.1 Documents Included ...................................................................................................... 5 2.1.2 Documents Excluded ..................................................................................................... 5 2.1.3 Search Locations............................................................................................................ 5 2.1.4 Related Documents Not Found...................................................................................... 6 2.2 Compilation .......................................................................................................................... 6 2.2.1 Electronic Copies of Documents.................................................................................... 6 2.2.2 Collection of Information .............................................................................................. 7 2.3 Database Organization........................................................................................................ 10 2.3.1 Database - Tables......................................................................................................... 11 2.3.2 Database - Forms ......................................................................................................... 11 2.3.3 Database - Queries ....................................................................................................... 11 2.3.4 Database - Reports ....................................................................................................... 12 2.3.5 Database User .............................................................................................................. 12 2.4 Quality Assurance/Quality Control .................................................................................... 12 Section 3.0 Task 3 – Synthesis..................................................................................................... 17 3.1 Introduction......................................................................................................................... 17 3.2 Geologic Framework .......................................................................................................... 17 3.2.1 Introduction.................................................................................................................. 17 3.2.2 Geologic Nomenclature ............................................................................................... 18 3.2.3 Regional Geologic Characteristics............................................................................... 18 3.2.4 Palouse Basin Geologic Characteristics....................................................................... 19 3.2.4.1 Pullman-Moscow Subarea .................................................................................... 19 3.2.4.2 Northern Subarea .................................................................................................. 21 3.2.4.3 Western Subarea ................................................................................................... 22 3.2.5 Description of Stratigraphic and Structural Features................................................... 22 3.2.5.1 Crystalline Basement Rocks ................................................................................. 22 3.2.5.2 Imnaha Formation................................................................................................. 24 3.2.5.3 Grande Ronde Formation...................................................................................... 24 3.2.5.4 Wanapum Formation ............................................................................................ 26 3.2.5.5 Saddle Mountains Formation................................................................................ 26 3.2.5.6 Structural Features ................................................................................................ 27 3.3 Hydrogeologic Framework................................................................................................. 28 3.3.1 Introduction.................................................................................................................. 28 3.3.2 Aquifer Identification and Temporal Growth of Knowledge ...................................... 28 3.3.2.1 Aquifer Identification............................................................................................ 28 3.3.2.2 Temporal Growth of Knowledge of the Aquifers................................................. 30 ii Palouse Ground Water Basin Framework Project FINAL report 3.3.3 Characteristics of the Lower Aquifer........................................................................... 33 3.3.3.1 Water-Producing Zones ........................................................................................ 34 3.3.3.2 Hydraulic Characteristics...................................................................................... 35 3.3.3.3 Aquifer Boundaries............................................................................................... 38 3.3.3.4 Horizontal and Vertical Hydraulic Gradients ....................................................... 40 3.3.3.5 Temporal Water-Level Changes........................................................................... 40 3.3.4 Characteristics of the Upper Aquifer ........................................................................... 42 3.3.4.1 Water Producing Zones......................................................................................... 42 3.3.4.2 Hydraulic Characteristics...................................................................................... 42 3.3.4.3 Aquifer Boundaries............................................................................................... 43 3.3.4.4 Horizontal and Vertical Hydraulic Gradients ....................................................... 43 3.3.4.5 Temporal Water-Level Changes........................................................................... 43 3.3.5 Ground-Water Flow Systems....................................................................................... 43 3.3.5.1 General Flow System Theory ............................................................................... 43 3.3.5.2 Ground-Water Flow Systems in the Palouse Basin .............................................. 44 3.4 Water Balance..................................................................................................................... 45 3.4.1 Introduction.................................................................................................................. 45 3.4.2 Surface Water Gain/Loss ............................................................................................. 46 3.4.3 Surface Sediment Water Balance................................................................................. 49 3.4.3.1 Ground-Water Recharge ....................................................................................... 49 3.4.3.2 Ground-water Discharge....................................................................................... 54 3.4.3.3 Change in Storage................................................................................................. 54 3.4.4 Upper Aquifer Water Balance...................................................................................... 54 3.4.4.1 Ground-Water Recharge ....................................................................................... 55 3.4.4.2 Ground-Water Discharge...................................................................................... 56 3.4.4.3 Change in Storage................................................................................................. 57 3.4.5 Lower Aquifer Water Balance ..................................................................................... 58 3.4.5.1 Ground-Water Recharge ....................................................................................... 58 3.4.5.2 Ground-Water Discharge...................................................................................... 59 3.4.5.3