IPSWICH RIVER Watershed Action Plan Horsley & Witten, Inc. Sandwich, Massachusetts October 2003 The Commonwealth of Massachusetts Executive Office of Environmental Affairs 251 Causeway Street, Suite 900 Boston, MA 02114-2119 Mitt Romney GOVERNOR Kerry Healey LIEUTENANT GOVERNOR Tel: (617) 626-1000 Ellen Roy Herzfelder Fax: (617) 626-1181 SECRETARY http://www.mass.gov/envir October 29, 2003 Dear Friends of the Ipswich River Watershed: It is with great pleasure that I present the 5-Year Watershed Action Plan for the Ipswich River Watershed. Over the next five years the plan will be used to guide local and state environmental efforts within the Ipswich River Watershed, as well as implement the goals of the Executive Office of Environmental Affairs. Our goals include the improvement of water quality; restoring natural flows to rivers; protecting and restoring biodiversity and habitats; improving public access and balanced resource use; improving local capacity; and promoting a shared responsibility for watershed protection and management. The Ipswich River Watershed Action Plan was developed with input from a broad range of interests. This unique approach helps us focus on the problems and challenges that are identified with the stakeholders and community partners in each watershed, rather than being decided solely at the state level. The Ipswich River has faced extremely low flow periods and other environmental impacts. The action strategies in the plan as they relate to these issues address: • Water Conservation • Stormwater Management • Alternate Sources of Water Supply • Wastewater Alternatives • Land Planning I commend everyone that was involved in this endeavor. Thank you for your dedication, perseverance, and commitment. If you are not currently a participant, I strongly encourage you to become active in the Ipswich River Watershed restoration and protection efforts. Regards, Ellen Roy Herzfelder This Watershed Action Plan is a critical component of the efforts now occurring to understand the problems in the watershed. The Plan includes a variety of best management measures to help restore the Ipswich River and to improve conditions in the watershed. The Plan is the result of four years of collaboration between a broad representation of interests in the Ipswich River Watershed. It has formed the basis for the creation of the Ipswich River Watershed Management Council and it lays the framework for future activities for the Council. This plan is a working document. It should be viewed as a tool for municipalities, water supply boards, watershed advocates and state government to help achieve the goal of excellent water quality and suffi cient water quantity for drinking water, fi sheries, recreation and other uses. This project was funded through a grant made available from the Executive Offi ce of Environmental Affairs, the former Massachusetts Watershed Initiative. TABLE OF CONTENTS Page EXECUTIVE SUMMARY i 1.0 BACKGROUND 1-1 1.1 Introduction 1-1 1.2 The Watershed Approach 1-1 1.3 Outreach and Public Participation 1-4 1.4 Project Background 1-5 1.5 Goals and Objectives 1-6 2.0 THE IPSWICH RIVER WATERSHED 2-1 2.1 Watershed Values 2-1 2.2 Characteristics of the Ipswich River Watershed 2-2 2.3 Watershed Hydrology 2-5 2.4 Biota and Habitat 2-5 2.4.1 Aquatic Habitat 2-5 2.4.2 Fish and Shellfi sh 2-6 2.4.3 Vegetation 2-6 2.5 Recreational Use 2-7 3.0 IMPAIRMENT OF THE IPSWICH RIVER WATERSHED 3-1 3.1 Overview 3-1 3.2 Low-Flow Problem 3-2 3.3 Low Dissolved Oxygen 3-3 3.4 Loss of Habitat 3-4 3.5 Loss of Biodiversity 3-5 3.5.1 Invasive Species 3-7 3.6 Pollution 3-7 3.7 Loss of Open Space and Land Use Changes 3-8 3.8 Loss of Recreational Opportunities 3-8 3.9 Loss of Other Uses 3-9 4.0 THE WATER BUDGET 4-1 4.1 Components of a Water Budget 4-1 4.2 Factors That Can Affect the Water Budget 4-1 4.3 Water Withdrawals 4-1 4.4 The Importance of Groundwater Recharge in Maintaining River Basefl ow 4-5 4.4.1 Natural Groundwater Recharge 4-5 4.4.2 Reduced Groundwater Recharge Due to Groundwater Withdrawals 4-6 4.4.3 Effects of Surface Water Withdrawals 4-8 4.4.4 Transfer of Water Outside of the Watershed 4-9 Ipswich River Watershed Action Plan Horsley & Witten, Inc. 4.5 Effects of Impervious Areas 4-11 4.5.1 Reduced Recharge of Groundwater 4-11 4.5.2 Increased Runoff Rates 4-11 4.6 Dams 4-13 4.7 Summary 4-14 5.0 SUMMARY OF ANALYSIS 5-1 5.1 Summary of Ipswich River Flow Modeling by the USGS 5-1 5.1.1 Summary of the USGS Model (USGS, 2000) 5-1 5.1.2 Summary of the Effects of Alternative Water Management Options on Streamfl ow in the Ipswich River (USGS, Draft, 2001) 5-4 5.2 Aquatic Habitat Studies in the Ipswich River 5-6 5.2.1 Aquatic Habitat Minimum Streamfl ow Study 5-7 5.2.2 Existing Habitat Conditions Survey 5-7 5.2.3 Target Fish Community and Streamfl ow Recommendations 5-9 5.3 Future Community Growth 5-10 6.0 MANAGEMENT OPTIONS FOR IPSWICH RIVER BASIN 6-1 6.1 Water Conservation 6-3 6.2 Stormwater Management 6-6 6.3 Alternative Sources of Water Supply 6-10 6.3.1 Importing Water From Out-of-Basin Sources 6-10 6.3.2 Increased Water Storage 6-13 6.3.3 Other Water Sources 6-16 6.4 Wastewater Alternatives 6-16 6.5 Summary of Benefi ts from Proposed Management Strategy 6-20 6.6 Land Planning 6-20 7.0 REFERENCES LIST OF TABLES Table 1. Water Withdrawals and Interbasin Transfers in the Ipswich Watershed Table 2. Summary of Buildout Analysis for Towns within the Ipswich Watershed Table 3. Population Forecasts for Permitting Withdrawals Table 4. Summary of Streamfl ow Targets and Defi cits by Watershed Table 5. Potential Benefi ts of the 150% Stormwater Infi ltration Policy Table 6. Stormwater Management Goals Table 7. Benefi ts of Proposed Management Strategies Table 8. Impacts of Potential Water Demands Ipswich River Watershed Action Plan Horsley & Witten, Inc. LIST OF FIGURES Figure 1 Ipswich River Basin Figure 2 Ipswich River Watershed Figure 3 Land Use in the Ipswich River Watershed Figure 4 Total Water Withdrawals 1999 Figure 5 Groundwater Withdrawals 1999 Figure 6 Surface Water Withdrawals 1999 Figure 7 Water Transfer Out of Ipswich Watershed 1999 Figure 8 Flow as 50% Frequency Occurrence at South Middleton Station Figure 9 Flow as 99.8% Frequency Occurrence at South Middleton Station Figure 10 Percentage of Time With No Flow in the Ipswich River Would Occur Under Alternative Management Scenarios at Reach 8 Figure 11 Existing Ipswich River Fish Community Figure 12 Ipswich River Target Fish Community Figure 13 Ipswich River Basin with Potential Recharge Areas APPENDICES APPENDIX A Ipswich River Watershed Action Plan Preliminary Action Strategies Ipswich River Watershed Action Plan Horsley & Witten, Inc. EXECUTIVE SUMMARY The Ipswich River is an important economic and ecological asset to northeastern Massachusetts. This small coastal plain river, which fl ows about 45 meandering miles from source to sea, provides drinking water to over 330,000 residents and thousands of businesses in fi fteen northeastern Massachusetts communities. Since pre-colonial times, the Ipswich River supported productive and diverse fi sheries, including anadromous species such as smelt, alewives, shad and salmon, and fl ow-dependent resident freshwater species such as brook trout and fallfi sh. These bountiful fi sheries, along with the extensive shellfi sh beds of the Ipswich River estuary, were a mainstay of the regional economy for centuries. During the early industrial era, the river provided “free” power to shipbuilders, tanneries, paper and textile mills. Today, the river is also an important recreational resource and a key part of the region’s burgeoning eco-tourism industry. The estuary is part of the Great Marsh ecosystem, and the river hosts important regional bio-reserves including the Ipswich River Wildlife Sanctuary and many privately- and publicly-owned forests, parks and reservations. The Ipswich River Watershed experienced less development and industrialization than nearby watersheds to the north and south, and thus was spared some of the pollution problems which affl icted rivers such as the Merrimack, Nashua and Charles. Since the Ipswich River was less polluted than others in the area, it became an important source of drinking water, not only for communities within the watershed but even more so for neighboring communities along the southern boundary and outside of the watershed. Today, much of the river’s water is pumped for municipal water supply and is being consumed at a rate which has left the river signifi cantly impaired. Approximately 80% is exported from the watershed, resulting in a signifi cant net loss of water to the river system. The impacts are evident in extremely low fl ows and periods of no fl ow that occur chronically during the summer months, and occasionally at other times of year when droughts coincide with seasonal water diversions to fi ll reservoirs. Fish kills and modifi cations to the species composition within the river ecosystem have been documented. Other adverse impacts, including extremely low dissolved oxygen in the upper watershed during the summer period, further degrade the river’s ecology. Other issues of concern include frequent hazardous waste contamination, which has affected a number of water supply sources, as well as general pollutant loading from several non-point sources. Concerns have been raised about the loss of function of some vegetated wetland areas due to desiccation and other factors.