2020 Commonwealth of the Northern Mariana Islands 305(b) and 303(d) Water Quality Assessment Integrated Report Photo: Scott Eck - Bird Island in Saipan’s Northeastern Coastal waters Bureau of Environmental and Coastal Quality September 2020 Editor & Contributing Author: Kathy Yuknavage Contributing Authors: Jonathan Arriola, David Benavente, Rodney Camacho, Erin Derrington, Malcolm Johnson, Larry Maurin, Denise Perez, and Travis Spaeth Maps: Rodney Camacho, Robbie Greene, and Kathy Yuknavage CONTENTS EXECUTIVE SUMMARY .................................................................................................................... 1 PART A. INTRODUCTION .......................................................................................................... 14 PART B. BACKGROUND INFORMATION ................................................................................... 15 B.1. ALL CNMI SURFACE WATERS .......................................................................................... 15 B.1.1. Monitoring Water Quality of Saipan and Mañagaha ............................................. 17 B.1.2. Monitoring Water Quality of Rota and Tinian ........................................................ 17 B.1.3. Monitoring Water Quality of Northern Islands ...................................................... 18 B.1.4. CNMI Classification of Marine Coastal Water Uses ................................................ 18 B.1.4.1. Class AA Coastal Waterbodies .................................................................................... 18 B.1.4.2. Class A Coastal Waterbodies ....................................................................................... 21 B.1.5. CNMI Classification of Fresh Surface Waterbodies (Streams, Wetlands and Lakes) Uses 24 B.2. WATER POLLUTION CONTROL PROGRAM ..................................................................... 26 B.2.1. Water Quality Surveillance/Nonpoint Source Program ......................................... 26 B.2.1.1. CNMI Water Quality Standards ................................................................................... 26 B.2.1.2. Water Quality Monitoring and Notification ................................................................ 27 B.2.1.3. Section 401 Water Quality Certification Program ...................................................... 28 B.2.2. Marine Biological Monitoring Program .................................................................. 28 B.2.3. Wastewater, Earthmoving, and Erosion Control Program ..................................... 29 B.2.3.1. Wastewater Treatment Disposal Regulations ............................................................ 29 B.2.3.2. Earthmoving and Erosion Control Regulations ........................................................... 30 B.2.4. Safe Drinking Water and Ground water Management Program ............................ 31 B.2.4.1. Safe Drinking Water Regulations ................................................................................ 31 B.2.4.2. Well Drilling and Well Operation Regulations ............................................................ 31 B.2.4.3. Underground Injection Control Regulations ............................................................... 31 B.3. COST/BENEFIT ASSESSMENT .......................................................................................... 31 B.3.1. Costs ........................................................................................................................ 32 B.3.2. Benefits ................................................................................................................... 32 B.4. SPECIAL STATE CONCERNS AND RECOMMENDATIONS ................................................. 33 B.4.1. Erosion and Sedimentation ..................................................................................... 33 B.4.2. Failing Septic Systems, and Illicit, and Permitted Wastewater Discharges ............ 34 B.4.3. Feral and Domesticated Animal Fecal Contamination ........................................... 36 B.4.4. Toxins and Heavy Metal Contamination of Fish and Other Biota .......................... 37 B.4.5. Climate Related Severe Storm Event Impacts ........................................................ 37 PART C. SURFACE WATER MONITORING ASSESSMENT ........................................................... 39 C.1. MONITORING PROGRAMS ............................................................................................. 39 C.1.1. Coastal Marine Water Quality Monitoring and Notification .................................. 39 C.1.2. Marine Biological Criteria Monitoring Program ..................................................... 40 C.1.3. Surface Water Quality Monitoring Program ........................................................... 41 C.1.4. Other Outside Information and Data Used for Assessment Purposes ................... 42 C.1.4.1. WERI Fish Tissue and Biota Contaminant Studies ....................................................... 42 C.1.4.2. UOG and NOAA-CRED Studies .................................................................................... 43 C.1.4.3. qPCR-MST Study of Saipan Coastal Waters ................................................................ 44 C.1.4.4. LaoLao Bay Watershed Restoration Project ............................................................... 44 C.1.4.5. CNMI Division of Fish & Wildlife Fresh Aquatic Survey .............................................. 44 C.2. ASSESSMENT METHODOLOGY ....................................................................................... 45 C.2.1. Waterbody Segmentation - Watershed Approach ................................................. 45 C.2.2. CNMI Designated Uses ............................................................................................ 48 C.2.3. Criteria Used to Assess Coastal Marine Waterbodies’ Designated Uses ............... 51 C.2.3.1. Coastal Marine Waters Propagation of Aquatic Life Criteria ...................................... 52 C.2.3.2. Coastal Marine Water Fish and Shellfish Consumption Criteria ................................. 56 C.2.3.3. Coastal Marine Waters Recreational Use Criteria ...................................................... 56 C.2.3.4. Coastal Marine Waters Aesthetic Enjoyment and Other Uses Criteria ...................... 57 C.2.4 Criteria Used to Assess Fresh Surface Waterbodies’ Designated Uses .................. 61 C.2.4.1. Fresh Surface Water Propagation of Aquatic Life Criteria .......................................... 62 C.2.4.2. Fresh Surface Water Fish/Shellfish Consumption Criteria .......................................... 63 C.2.4.3. Fresh Surface Water Recreational Use Criteria .......................................................... 63 C.2.4.4. Potable Freshwater Supply Criteria ............................................................................ 64 C.2.4.5. Fresh Surface Water Aesthetic Enjoyment and Other Uses Criteria .......................... 64 C.2.5. Five-Part Consolidated Assessment and Listing Method Categories ..................... 64 C.2.5.1. CALM Category 1 ......................................................................................................... 65 C.2.5.2. CALM Category 2 ......................................................................................................... 65 C.2.5.3. CALM Category 3 ......................................................................................................... 66 C.2.5.4. CALM Category 4 ......................................................................................................... 66 C.2.5.5. CALM Category 5 ......................................................................................................... 67 C.3 ASSESSMENT RESULTS ................................................................................................... 68 C.3.1. Five-Part Categorization All CNMI Surface Waters ................................................. 68 C.3.2. Section 303(d) List and TMDL Development Status ............................................... 68 C.3.2.1. Criteria for Removal of Water Segment/Pollutant Combinations from the 303(d) List 77 C.3.2.2. CNMI Waters Removed from the 303(d) List .............................................................. 78 C.3.3. CNMI Summaries of Designated Use Support ........................................................ 83 C.3.4. Section 314 (Clean Lakes Program) ........................................................................ 91 C.3.5. Five-Part Categorization of Saipan’s and Mañagaha’s Surface Waters .................. 95 C.3.5.1. KALABERA - Waterbody Segment 12 ........................................................................ 102 C.3.5.2. TALOFOFO - Waterbody Segment 13 ........................................................................ 105 C.3.5.3. KAGMAN - Waterbody Segment 14 .......................................................................... 109 C.3.5.4. LAOLAO - Waterbody Segment 15 ............................................................................ 113 C.3.5.5. DANDAN - Waterbody Segment 16........................................................................... 116 C.3.5.6. ISLEY - Waterbody Segments 17A and 17B ............................................................... 118 C-3.5.7. SUSUPE - Waterbody Segment 18 ............................................................................ 126 C.3.5.8. WEST TAKPOCHAU – Waterbody Segments 19A, 19B, and 19C ..............................