Water Supply/Demand Status Report for the Delaware River Basin September 2005 EXECUTIVE SUMMARY................................................................................................................IV PURPOSE STATEMENT .................................................................................................................. V STUDY LIMITATIONS..................................................................................................................... V REPORT OVERVIEW......................................................................................................................VI I. INTRODUCTION TO THE DELAWARE RIVER BASIN........................................................1 1.1 OVERVIEW OF THE DELAWARE RIVER BASIN ..............................................................................1 II. WATER SUPPLY BACKGROUND AND THE DELAWARE RIVER BASIN COMMISSION (DRBC)......................................................................................................................3 2.1 DEFINITION OF “WATER SUPPLY” ................................................................................................3 2.2 DELAWARE RIVER BASIN COMMISSION .......................................................................................3 2.2.1 The Delaware River Basin Compact....................................................................................3 2.2.2 Rules of Practice and Procedure..........................................................................................3 2.2.3 Water Code............................................................................................................................3 2.2.4 Comprehensive Water Resources Plan for the Delaware River Basin...............................4 2.3 THE U.S. SUPREME COURT DECREE OF 1954 ...............................................................................4 2.4 “GOOD-FAITH”RECOMMENDATIONS/DROUGHT OPERATING PLANS ..........................................5 III. STUDY PURPOSE, METHODOLOGY AND DATA SOURCES ...........................................7 3.1 STUDY PURPOSE ...........................................................................................................................7 3.2 METHODOLOGY ............................................................................................................................7 3.2.1 Demand Forecasting Model.................................................................................................8 3.2.2 Delineation of Delaware River Basin into Sub-basins........................................................8 3.2.3 Alternative Climate Conditions............................................................................................8 3.2.4 Basis for Water Use Assessment and Demand Projections.................................................8 IV. WATER AVAILABILITY..........................................................................................................11 4.1 SURFACE WATER SUPPLY...........................................................................................................11 4.1.1 Reservoir Storage in the Basin...........................................................................................11 4.1.2 Consumptive Use Replacement ..........................................................................................11 4.1.3 Surface Water Storage and Availability Calculations.......................................................13 4.2 GROUND WATER STORAGE ........................................................................................................14 4.2.1 Physiographic provinces/generalized geology...................................................................14 4.2.2 “Safe yield”.........................................................................................................................14 4.2.2.1 Base flow Recurrence Intervals....................................................................................14 4.2.2.2 Percentage of Average Annual Recharge.....................................................................14 4.2.3 Critical/Protected Areas .....................................................................................................15 4.2.3.1 Potomac-Raritan-Magothy (PRM) Aquifer: Critical Area No. 2 .................................15 4.2.3.2 Ground Water Protected Area (GWPA).......................................................................15 4.2.4 Contaminated Aquifers.......................................................................................................15 4.2.5 Ground Water Storage/Yield..............................................................................................17 4.2.6 Surface Water Storage and Availability Calculations.......................................................17 V. ANALYSIS OF CURRENT AND PROJECTED WATER DEMANDS..................................18 5.1 EXISTING SURFACE AND GROUND WATER DEMANDS ...............................................................18 5.1.1 Uses by Sector .....................................................................................................................18 5.2 EFFECTS OF CLIMATE AND PEAKING FACTORS ON DEMAND .....................................................18 DRBC Water Supply/Demand Status Report for the Delaware River Basin i 5.3 USES BY SUB-BASIN....................................................................................................................19 5.4 TOTAL WITHDRAWALS CONSUMPTIVE USE &DELAWARE RIVER BASIN EXPORTS .................20 5.5 CONSUMPTIVE USE AND EQUIVALENT IMPACT FACTOR............................................................22 5.6 SENSITIVITY TESTING OF CONSUMPTIVE USE ESTIMATES.........................................................24 5.7 CURRENT AND FORECAST WATER USE BY SECTOR ...................................................................25 VI. RESOURCE ASSESSMENT......................................................................................................30 6.1 DELAWARE RIVER BASIN ...........................................................................................................30 6.1.1 Surface Water Assessment .................................................................................................30 6.1.2 Ground Water Assessment .................................................................................................30 6.2 INDIVIDUAL SUB-BASINS ............................................................................................................33 6.1.1 Surface Water Assessment .................................................................................................33 6.1.2 Ground Water Assessment .................................................................................................34 VII. RECOMMENDATIONS ...........................................................................................................35 7.1 IMPROVE THE COLLECTION AND MANAGEMENT OF WATER USE DATA ...................................35 7.2 ADDRESS KEY AREAS OF UNCERTAINTY ...................................................................................35 7.3 FOCUS ON MOST STRESSED SUB-BASINS....................................................................................35 7.4 MITIGATE CONSUMPTIVE USE IMPACTS.....................................................................................36 7.5 IMPROVE DEMAND PROJECTIONS FOR THE POWER SECTOR ......................................................36 7.6 DEVELOP AND INTEGRATE INSTREAM FLOW CRITERIA .............................................................36 APPENDICES ....................................................................................................................................38 DRBC Water Supply/Demand Status Report for the Delaware River Basin ii LIST OF FIGURES: FIGURE 1.1 THE DELAWARE RIVER BASIN (DRB) ..................................................................................................2 FIGURE 3.1 DELAWARE RIVER BASIN (DRB) SUB-BASIN DELINEATIONS ................................................................9 FIGURE 4.1 GENERALIZED GEOLOGIC PROVINCES IN THE DELAWARE RIVER BASIN .............................................16 FIGURE 5.1 WITHDRAWALS,CONSUMPTIVE USE AND MAJOR EXPORTS FROM THE DELAWARE RIVER BASIN .....21 FIGURE 5.2 LOCATION OF POWER GENERATING FACILITIES IN THE DELAWARE RIVER BASIN ...............................23 FIGURE 5.3 TOTAL WATER USE (DRY YEAR) - 1995, 2020 AND 2040 PROJECTED WATER DEMAND BY SECTOR....26 FIGURE 5.4 CONSUMPTIVE WATER USE (DRY YEAR) - 1995, 2020 AND 2040 PROJECTED WATER DEMAND BY SECTOR.........................................................................................................................................................27 FIGURE 6.1 CONSUMPTIVE SURFACE WATER WITHDRAWALS (DRY YEAR): AVERAGE AND PEAK MONTH (JULY) VALUES.........................................................................................................................................................31 FIGURE 6.2 GROUND WATER WITHDRAWALS (DRY YEAR): AVERAGE AND PEAK MONTH (JULY) VALUES ..........32 LIST OF TABLES: TABLE 2.1 INTERSTATE OPERATION FORMULAS DURING PERIODS OF DROUGHT....................................................5 TABLE 3.1 PRECIPITATION STATISTICS FOR 1995 AND 1996 IN THE DELAWARE RIVER BASIN................................8 TABLE 4.1 RESERVOIRS IN THE DELAWARE RIVER BASIN: CAPACITY, LOCATION AND PURPOSE. .........................12 TABLE