St. Mary’s River Watershed Characterization Spring 2016 Prepared by the St. Mary’s River Watershed Association, Inc. in partnership with St. Mary’s County Government, Maryland Department of Natural Resources, St. Mary’s College of Maryland, and local agencies and businesses. 1 BLANK PAGE 2 St. Mary’s River Watershed Characterization Spring 2016 a supporting document to the Watershed Restoration Action Strategy for the St. Mary’s River St. Mary’s River Watershed Association, Inc. in partnership with St. Mary’s County Government, Maryland Department of Natural Resources, St. Mary’s College of Maryland, and local agencies and businesses. For more information, please contact Bob Lewis, St. Mary’s River Watershed Association, 301-737-2903 or
[email protected]. 3 BLANK PAGE 4 TABLE OF CONTENTS GLOSSARY viii EXECUTIVE SUMMARY 1-1 CONTRIBUTORS TO THE WATERSHED CHARACTERIZATION 2-1 INTRODUCTION 3-1 Background 3-1 Location 3-2 Purpose of Characterization 3-2 HERITAGE: History of Human Interactions with the Watershed 4-1 Prehistoric Peoples 4-1 Colonial to Present Days (ca. 1630-2008) 4-2 Human Usage of the St. Mary’s River Drainage in History 4-3 Vegetation Changes in the St. Mary’s River Drainage 4-5 Historic Sedimentation Rates in the St. Mary’s River 4-6 Determining Historical Ecological Change to the River 4-7 WATER QUALITY 5-1 Water Quality Standards and Designated Uses 5-1 Use Impairments (Non-supporting Uses) 5-2 Impaired Waters in St. Mary’s River Watershed St. Mary’s River St. Mary’s Lake What Causes Water Quality Impairment? [Text Box] 5-5 Use Restrictions and Advisories 5-6 What Are the Effects of Nutrient Over-Enrichment? [Text Box] 5-7 Antidegradation 5-9 Water Quality Indicators – Setting Priority for Restoration and Protection 5-11 Water Quality Monitoring 5-13 St.