MICHIGAN SOURCE WATER ASSESSMENT PROGRAM Michigan Section AWWA Annual Conference September 15, 2000 Bradley B. Brogren, P.E. Michigan Department of Environmental Quality Michael J. Sweat, P.G. U.S. Geological Survey

1996 Amendments to the Federal SAFE DRINKING WATER ACT n Require States to: Identify the areas that supply public drinking water.Identify the areas that supply public drinking water. Inventory contaminants and assess water susceptibility to contamination.Inventory contaminants and assess water susceptibility to contamination. Inform the public of the results.Inform the public of the results.

STATE SOURCE WATER ASSESSMENT PROGRAM SCHEDULE n Final Guidance Published by US-EPA August 6, Requires Submittal of State SWAP by February Requires Submittal of State SWAP by February 1999 Michigan Submitted to USEPA on February 1, 1999 Michigan Submitted to USEPA on February 1, USEPA Approval of Programs by November USEPA Approval of Programs by November 1999 USEPA Approved on October 22, 1999 USEPA Approved on October 22, Allowable Extension to Complete by May Allowable Extension to Complete by May 2003 Extension Granted by USEPA Extension Granted by USEPA

MICHIGAN PUBLIC WATER SUPPLIES REQUIRING ASSESSMENTS n Noncommunity, Groundwater Supplies Nontransient =1720 Transient = 8930 Nontransient =1720 Transient = 8930 n Community, Groundwater Supplies =1250 n Community, Surface Water Supplies = n Community, Surface Water Supplies = 70 Total= Estimated Number of Sources to Assess is 18,000

MICHIGAN SOURCE WATER ASSESSMENT PROGRAM n Funded through Drinking Water Revolving Fund n Formed SWAP Advisory Committees to Implement Technical Advisory Subcommittee Public Advisory Subcommittee n Utilize Vulnerability Assessments, Sanitary Surveys, Existing Monitoring Data Existing Monitoring Data n Incorporate Wellhead Protection Program n Include State Pesticide Management Plan n Use Watershed Initiative Assessments n Reference Clean Water Act Assessments

MICHIGAN SWAP WATER SUPPLY ASSESSMENT CATEGORIES 1. Noncommunity, Groundwater Supply Assessments 1. Noncommunity, Groundwater Supply Assessments 2. Wellhead Protection Programs for Community, Groundwater Supplies 2. Wellhead Protection Programs for Community, Groundwater Supplies 3. Community, Surface Water Assessments 3. Community, Surface Water Assessments l Inland Lakes and Rivers l Great Lakes Sources 4. Karst Groundwater Assessments 4. Karst Groundwater Assessments 5. Assessments for Remaining Community, Groundwater Supplies 5. Assessments for Remaining Community, Groundwater Supplies

WELLHEAD PROTECTION PROGRAMS FOR COMMUNITY, GROUNDWATER SUPPLIES n 1986 amendments to Federal Safe Drinking Water Act established WHP programs. –MDEQ program approved by USEPA. n A MDEQ approved local WHP Program is a Source Water Assessment with Susceptibility Determination. n Current WHP Activities include: –Low Tritium Designated Communities –Delineated Wellheads –Approved Local Programs n WHP Grant Program: –State $$ Match local WHP expenditures.

COMMUNITY, SURFACE WATER ASSESSMENTS n Inland Lakes and Rivers –Local Utility Records –LHD, USGS and SWQD Monitoring Data –USGS Hydrologic Watershed Delineation n Great Lakes Sources –Utility Monitoring Results and Modeling Data –Great Lakes Protocol with Neighboring States –Connecting Channels Flow Model

ASSESSMENT PROTOCOL for GREAT LAKES SOURCES n Initial Survey Raw Water QualityRaw Water Quality Operational ExperiencesOperational Experiences Contaminant Sources of ConcernContaminant Sources of Concern n Completing Assessment Site Specific for Shoreline ImpactsSite Specific for Shoreline Impacts Analyze Intake SensitivityAnalyze Intake Sensitivity Defines Critical Assessment ZoneDefines Critical Assessment Zone Define SusceptibilityDefine Susceptibility n Spill Assessments n Potential Treatment Impacts

KARST GROUNDWATER ASSESSMENTS n Aquifers subject to surface or near surface contamination –Identify Karst Areas –Inventory Noncommunity and Community Water Supply Wells –Conventional Groundwater Modeling Not Applicable –USGS to Assist with Assessments

COMMUNITY, GROUNDWATER ASSESSMENTS n For community supplies not implementing WHP. –Another basis for requesting 18 month extension from US-EPA for SWAP completion. n Assessments will be based on fixed radius approach at wellhead similar to noncommunity scoring. –200’ Standard; 2000 Major Isolation. –Assessments to be conducted by DWRPD district staff. –Assessments not as thorough as WHP. –Monitoring Waivers Limited –No Long Term Resource Management

SOURCE WATER ASSESSMENTS INCLUDE: n Delineation n Contaminant Source Inventory n Abandon Well Survey Methodologies Sensitivity Analysis Sensitivity Analysis n Susceptibility Determination

DELINEATION OF SOURCE WATER PROTECTION AREAS n For Ground Water  -Determined by Modeling Ten Year Time of Travel for WHPA  -Defined by Fixed Radius Approach for Noncommunity/Community Water Supplies  For Surface Water -Defined by Watershed Boundaries  -Defined by Flow Model  -Includes Critical Assessment Zone

ST. CLAIR RIVER - LAKE ST. CLAIR - DETROIT RIVER FLOW MODEL l Partnership - MDEQ, USGS, DWSD, USACE, NOAA l Phase I - Hydrodynamic Model –Define Grid Geometry, Bathymetry l Phase II - Water Quality Monitoring –Input Contaminant Sources –Hydraulic Loadings l Phase III - Particle Tracking –Spill Analyses, Contingency Planning

CONTAMINANT SOURCE INVENTORY n Identify and Inventory Contaminant Sources n Describe Contaminant Sources within Source Water Protection Area n Target Sources for Further Investigation n Collect and Interpret New Information n Verify Accuracy and Reliability of Information

SENSITIVITY ANALYSIS n Relative ease at which a contaminant can migrate to water supply source. n Measures inability of natural materials or hydrology conditions to protect source. n A function of intrinsic characteristics of the geologic materials that compose the land surface, and the saturated and unsaturated zones. n Independent of land use or contaminant characteristics. n Considers Well or Intake Construction

SUSCEPTIBILITY DETERMINATION n Required by USEPA for all Public Water Supply Sources n Determined using sensitivity analysis, source water protection area and contaminant inventory. n Describes potential for a contaminant to impact a source of drinking water. n Evaluates if contaminant could reach source at concentrations that could affect system’s ability to meet all regulatory requirements. n Also includes consideration of abandoned wells.

RESULTS OF SOURCE WATER ASSESSMENTS n Used by DWRPD and LHD’s to determine future monitoring waivers. n To Inform Public n To Initiate Source Water Protection Activities n Develop Contingency Planning

INFORMING THE PUBLIC n Reports Readily Available and Understandable –From Local Utility/Water Supplier Utilities required to notify customers of availability in Consumer Confidence Reports. Utilities required to notify customers of availability in Consumer Confidence Reports. –From MDEQ/LHD’s n Use of the Internet –MDEQ currently has SWAP and wellhead delineations/community status on department web site (

1999 SWAP ACCOMPLISHMENTS n Program Approved by USEPA n Over 3000 Noncommunity Assessments Compiled n More than 200 Communities Pursuing WHP n Initiated 4 Community Water Supply Pilot Assessments on the River Raisin n Initiated 3 Pilot Assessments on Great Lakes Sources n Developed Procedures and Completed 6 Pilot Assessments on Community, Groundwater Sources n Defined Grid Geometry and Conducted Preliminary Model Run for the St. Clair River

2000 SWAP WORKPLAN n Initiate 3000 More Noncommunity Assessments n Pursue Additional WHP Program Approvals n Complete Preliminary River Raisin Assessments n Complete Preliminary Great Lakes Assessments n Complete St. Clair - Detroit Rivers Connecting Channel Hydraulic Flow Model n Complete Karst Mapping and Inventory Sources n Finalize Community Groundwater Assessment Procedure and Initiate Assessments with FOS Staff n Initiate County Vulnerability Mapping Effort through MSU-IWR, GEM Centers and LHD’s MSU-IWR, GEM Centers and LHD’s n Meet with SWAP Committees, LHD’s, MSU, GEM Centers and Communities involved in SWAP

Michigan Surface Water Intakes

n SENSITIVITY -- DETERMINED FROM THE NATURAL SETTING OF THE SOURCE WATER AND THE CONSTRUCTION AND LOCATION OF THE INTAKE n SUSCEPTIBILITY -- IDENTIFIES FACTORS THAT MAY POSE A RISK WITHIN THE COMMUNITY’S SOURCE WATER AREA -- PROVIDES INFORMATION WITH RESPECT TO LISTED FACILITIES AND/OR LAND USES WITHIN THE SOURCE WATER AREA THAT SHOULD BE GIVEN GREATER PRIORITY AND OVERSIGHT IN IMPLEMENTING A SOURCE WATER PROTECTION PROGRAM

SENSITIVITY ANALYSIS AND SUSCEPTIBILITY DETERMINATION INLAND CONNECTING CHANNELS AND RIVERS GREAT LAKES SOURCES SENSITIVITY VERY HIGHHIGH MODERATE CONTAMINANT INVENTORY SUSCEPTIBILITY DETERMINATION LISTEDNON-LISTED VERY HIGH HIGH MOD. HIGH MOD.

Critical Critical Sensitivity Assessment Value Zone Value Zone Sensitivity Value is determined<25,0003,000 foot radius by the length of by the length of the intake times25, ,0002,000 foot radius the depth of the intake >125,0001,000 foot radius

Results of a CONTAMINANT SOURCE INVENTORY