RZV-T-91-OOX C2 ; 9AN ',AFY it",I~ iston~ ~gds um~iLrTi~> air SeaGrant OeIjository Water Quality and Fisheries NarragansettBay Ahn Delbannetand VirginiaLee OO~~s P-12586 RIU-T-91-001 OPSY&M5OUIICj'L Cf'NItI CRP+ This publication is sponsoredby NOAA Office of SeaGrant, U,S. Departmentof Commerce,under Grant ¹NA89AA-D-SG-082, The U.S.Government is authorizedto produceand distribute reprints for governmentalpurposes notwithstanding any copyrightnotation that may appear heron. Additional copies of this publication are available from: Rhode Island Sea Grant Publications, University of Rhode Island Bay Campus,Narragansett, RI 02882-1197.Order P1258. National SeaGrant DepositoryPublication ¹RIU-T-91-001. Loan copies availablefrom the National SeaGrant Depository,Pell Li- braryBuilding, University of RhodeIsland Bay Campus, Narragansett, RI 02882-1197. Rhode Island Sea Grant, December 1991. Cover Photo: From GS. Goode. 1887. The fisheries and fishery industry of the United States. U.S. Dept. Interior, Washington, DC. SeaGrant is a nationalprogram dedicated to promoting the wise use and developmentof marine resourcesfor thepublic benefit. l,oANCOPY ONLY Historical Trends Water Quality and Fisheries Narragansett Bay A Reportto NationalOcean Pollution Program ONce NationalSea Grant ComegeR~im NationalOceanic and AtmosphericAdministration U.S. Departmentof Commerce %ashington,D.C. 2023$ Alan Desbonnetand Virginia Lee Coastal Resources Center GraduateSchool of Oceanography Universityof Rhodebland Narragansett,M 02882 Mapping: Neil K. Christerson URI Department of Marine Affairs Publishedby Rhode Bland Sea Grant December 1991 Printed on RecycledPaper ~ ts~j Table of Contents Acknowledgments ,...iv ChapterI. Profile of NarragansettBay .... ~ ~..........~ ..............,.........,.~........................ 1 The Physical Environment............,.......................................,........... 1 GeologicalOverview...,.... Climate.. Freshwater Inputs Circulation .....7 Major Uses. ..... 8 ShorelineDevelopment ... 8 Recreation. .....9 Fishing 10 Shipping 10 Industry ....................................... ....11 Chapter2. Bay Issuesand Management:An Overview ..13 Issues 13 ComprehensiveManagement 13 Pollution ................ 14 Risk from Contaminated Fish and Shellfish ............. 1 4 ShorelineDevelopment ,......... 1 4 Enforcement Issues. ............... 1 5 Dredging . ....... 1 5 Permitting Process. 15 Bay Managers The NarragansettBay Project A Major ResearchInitiative ... ...17 SaveThe Bay A PotentEnvironmental Advocacy Group ....17 Chapter 3. The Providence and Seekonk Rivers: Growth and Pollution .......,...... 19 Colonial NarragansettBay ...19 The Industrial Revolution .........................,...................,.. ...20 From 1900 to World War II. ....23 From the Postwar Era to 1970. ,...28 From 1970 to the Present. ....29 Chapter4. Trendsin WaterQuality in Upper Nanegansen Bay: Providenceand SeekonkRivers ~ $$~~ ~~ 33 Organic Carbonand DissolvedOxygen ....... 34 Sources of BOD . ,....,. 34 BOD Loading ......,. .....36 DissolvedOxygen Concentrations . ,...,38 Nutrients ...................... Sources of Nutrients . Nutrient Loading .. .....40 Toxics ......,........................,. ,....42 Sources of Metals ...... ,....42 Metals Loadings Sources of Organotoxins Organotoxin Loadings 46 Sourcesof PetroleumHydrocarbons. HydrocarbonLoadings. ....47 Pathogens ....48 Sourcesof Pathogens 48 Pathogen Loadings .,49 Chapter5. Trendsin LowerNarragansett Bay Water Quality....... 51 DissolvedOxygen, ............................. 51 Nutrients . 54 Nitrogen. ...,54 Phosphate ...56 Silica. ....56 Plankton ....57 Implications for Eutrophication ....58 Toxins. Metals Petroleum Hydrocarbons 63 PCBs. Waterborne Pathogens. , .....65 GeneralConclusions - Upper and Lower Bay .....66 Chapter6. Trendsin WaterQuality in Mount HopeB ay........ ~ ................,...............67 Water Quality Concerns . 69 Bacterial Contamination. ... ...... 69 Toxics Contamination .. 70 Trendsin PollutantLoadings ........... 70 CSOs ........... 70 Rivers ... 7 1 POTWs .....71 Physicaland Biological Trends ' ........... 73 Physical Trends .......... 73 Potentialfor Eutrophicationand Anoxia. .....76 Biological Trends ...77 General Conclusions . ........... 8 1 Chapter7. Trendsin NarragansettBay Fisheries .....83 Finfisheries .......84 Anadromous Fisheries .....84 Migratory Fisheries . ..85 Bay-Based Fisheries. ........... 87 Summary-Finfisheries . .....,. , 89 Shellftsheries............... The OysterIndustry. The Hard Clam Fishery ........... 92 References 95 This document should be referenced as: Desbonnet,A. andV. Lee. 1991. HistoricalTrends: Water Quality and Fisheries,Narragansett Say. The Universityof RhodeIsland Coastal ResourcesCenter Contribution No. 100and NationalSea Grant Publication ¹RIU-T-91-001.Graduate School oF Oceanography, Narragansett, RI. 101 pp. Chapter 1 %gute 1.1 Narragansett8ay. Datapmvded by R/QlS t 990!, Profile of Narragansett Bay Geologlcaf Overview sediments. The scarpis often unvegetated and steeply sloping. The most erosion The bay bottom is composed of resistant shorelines are bedrock. In sheltered glacially derived sedimentscovered with up waters where sediments accumulate, salt to 15 m of silt and sand eroded from land over marshes flourish and overlie the rock, sand, the past8,000-12,000 years. In general,the or silt; however,salt marshesmake up only sediments tend to be sand toward the mouth approximately3% of the total open-water of the bay, grading to mud and silt in the area of the bay Halvorsen and Gardiner, upper reaches which receive most of the 1976!,Compel toestuarieslike Chesapeake riverineand wastewater loadings McMaster, Bay and Indian RiverLagoon, Narragansett 1960!. Because the watershed was scoured Bay supports relatively little vegetation, during the most recent glaciation event, Eelgrassbeds are limited to patches.A 1978 sedimentloads arriving to the bayfrom rivers shorelinesurvey by Boothroydand Al-Saud are generallysmall, and the quantityof total 978! revealed that one-fourth of the natural suspended matter in the bay is minor. shorelinehad been replacedby man-made Suspendedsediment concentrations average structures such as piers, bulkheads, wharves, 4 mg/1,but va1uesas high as 100 mg/I have and pilings. Boothroyd is currently beenrecorded occasionally in theProvidence conducting a similar study ta updatethese River and may be attributed to sewage results. treatment plant inputs. Santschi et al. 984! determined that, on average,Narragansett Climate Bay presently accumulatessediment at a rate of 0.3 mrn per year. Narragansett Bay is situated in a The bay's shoreline is indented and temperate climate zone which imparts a generallysteeply sloping, affording sweeping marked seasonality to air and water views of the bay. Becauseof the many temperatures. Annual air temperature islandsand small coves, the shorelineis quite averages10'C, rangingfrom temperaturesof long relative to the size of the bay, The 1.7'C for January February the coldest shoreline is varied, ranging from rocky months!to 22.0'C for July thehottest! Figure headlands at the southernmost wave-washed 1.2!. Freezingtemperatures typically occur tips of the mainland and islands, to quiet 120 days per year, betweenNovember and covesfringed with salt marshscatteredaround March. Interestingly,annual air temperature the bay, to bulkheads in the urban hasincreased slightly since the early 1960s environmentsof themany smaH ports around Figure 1.2!. Surface water temperatures the bay and the city waterfrontat its head. also exhibit a warming trend from 1967to Thereare a few sandybeaches along 1985 Figure 1.2!, Surfacewatertemperature the bay in placeswhere longshorecurrents variesseasonally, from an averageof -0.5'C havebuilt small barrier spits acrossshallow in Decemberto 24'C in August Figure 1.2!. embaymentsor formedcuspate beaches such Annual water temperature averages9.9- as Conimicut Point. The most common 11.6'C Figure 1,2!. Ice coverduring winter shorelinealong the bay is a narrowbeach of months is generally limited to surfacewaters gravel,cobble, and boulders backed by a in the upper parts of the bay and adjacent scarp or bluff of unconsolidated glacial shallow coves. Chapter 1 25 190 20 170 I 150 10 130 O 5 49110 8 90 70 1996 1916 1936 1956 1976 Rgure1.8 Long-termtime weighted average annual precjpitationin theProvidence, Rl region,showing a gradual increase since 1915. Data taken from Pilson 989!, 10 is 115.3crn. Someseasonality in cloudcover is evident,with November December being themost cloudy period and July theleast. 9 188$1888 1873 1878 18N 1988 Figure 1.4 showsan averageannual WhaleRock - - - Alr Temp rise in relativesea level at Newport sincethe Fmtkaaoo early 1930s. This apparentsea level rise is due to a combination of local coastal Figure 1.2 Time weightedmonthly and average subsidence and eustatic sea level rise due to annualsea surface Jeffneset al., 1988!and air temperature Pilson, 1989! along Narragansett Bay, global warming trends. Hicks et al. 983! showingincreasesin air and watertemperature since determinedfrom 50 years of data that at least the mid-190Qs. Rir temperaturescollected NarragansettBay experiencesa relativerise southof Providence,Ri at T,F.Green State airport. SeeFigure 1.1 for bcationsof seasurface sampling in sealevel of approxitnately1,8 2.6cm per sites. decade. Rainfallaverages 106 cm per year, with little seasonalchange exhibited in Rgure 1A Long-termchanges in relativesea level heightat Newport,Rl showingan averageincrease