Spy Pond a Diagnostic Study

7.1-E-2

SPY POND

A DIAGNOSTIC STUDY 1980-1981

Massachusetts Department of Environmental Quality Engineering \ Anthony D. Cortese, Commissioner

DIVISION of WATER POLLUTION CONTROL Thomas C. McMahon, Director SPY POND :

A DIAGNOSTIC STUDY

1980-1981

EBEN W. CHESEBROUGH SANITARY BIOLOGIST

and

CHRISTINE DUERRING. AQUATIC BIOLOGIST

MASSACHUSETTS DEPARTMENT OF ENVIRONMENTAL QUALITY ENGINEERING DIVISION OF WATER POLLUTION CONTROL TECHNICAL SERVICES BRANCH

WESTBOROUGH, MASSACHUSETTS

DECEMBER 1982

Cover View of Arlington Boat Club, early 1900's Drawing by Robert Kerrigan adapted from a photograph from Spy Pond Stories (Balazs, 1973).

Publication #13,2i2-125-75-5-83-C.R. Approved by John J. Manton, State Purchasing Agent ACKNOWLEDGMENTS

The Division of Water Pollution Control wishes to thank those whose efforts made this Diagnostic Study possible. The following groups and individuals have been particularly helpful:

- George Minasian and the staff of the Lawrence Experiment Station who performed the analyses on the chemical and bacteriological samples from lake surveys;

- Frank P. Wright, Director of the Department of Properties and Natural Resources for the town of Arlington, who provided background and historical information on Spy Pond;

- Members of the Spy Pond Study Committee, especially Herbert M. Kagan, Chairman, Kevin G. Barbera, and John Hill.

- Nancy Flynn of Arlington, Massachusetts whose efforts were important in initiating proceedings for this study.

- The following individuals assisted in the surveys of Spy Pond and the analysis of the chemical and biological samples:

Mike Ackerman Judith Morrison Joan Beskenis Barbara Notini Richard McVoy Gayle Whittaker TABLE OF CONTENTS

ITEM PAGE

ACKNOWLEDGMENTS 2 LIST OF TABLES 4 LIST OF FIGURES 5 FOREWORD 6 INTRODUCTION Purpose of Study Background and History 8 WATERSHED CHARACTERISTICS 11 Physical Description 11 Development 18 LAKE CHARACTERISTICS 23 LIMNOLOGICAL DATA 27 Methods 27 Results 32 Physical 32 Chemical 36 Biological 60 Storm Drains 73 CONCLUSIONS 85 REFERENCES 86 APPENDIX A Chlorophyll a. Procedures 90 APPENDIX B Water Quality Data 92 APPENDIX C Phytoplankton Data 102 APPENDIX D A Note on Limnology and Lake Restoration Projects 107 APPENDIX E Description of Terms 116 APPENDIX F Algal Assay Results 121 APPENDIX G Record of Daily Precipitation 124 LIST OF TABLES

NUMBER TITLE PAGE

1 ARLINGTON, MASSACHUSETTS POPULATION INFORMATION 21

2 SPY POND MORPHOMETRIC DATA 25

3 SPY POND WATER QUALITY SAMPLING PROGRAM 28

4 SECCHI DISC READINGS - TIME, WEATHER, AND WATER 34 CONDITIONS

5 RESULTS OF CHEMICAL ANALYSES - STATION 1 41

6 RESULTS OF CHEMICAL ANALYSES - STATION 2 47

7 COMPARISON OF CONDUCTIVITY, CHLORIDE, AND TOTAL 52 SOLIDS IN FOUR LAKES

8 COMPARISON OF HISTORICAL DATA 61

9 RESULTS OF BACTERIOLOGICAL TESTING 63

10 SANITARY SURVEY DATA 67

11 STORM DRAIN DATA 74

12 STORM DRAINS - BRIEF DESCRIPTION 79

13 STORM DRAIN WET WEATHER SURVEY DATA 81

14 ALGAL ASSAY DATA FROM SPY POND 123 LIST OF FIGURES

NUMBER TITLE PAGE

1 SPY POND - GENERAL WATERSHED MAP 12 2 SPY - GENERAL SOILS MAP 14 3 LOCATION OF STORM DRAINS AND DRAIN SAMPLING STATIONS 16 3A WATERSHED STORM DRAIN SYSTEM AREAS 17 4 SPY POND - GENERAL LAND USE MAP 19 5 ' SPY POND BATHYMETRIC MAP AND LOCATION OF SAMPLING 24 STATIONS 6 SANITARY SURVEY STATION LOCATIONS ' 29 7 DEPTH-TIME DIAGRAM OF ISOTHERMS - STATION 1 33 8 SECCHI DISC TRANSPARENCY - STATIONS 1 AND 2 35 9 COMPARISON OF SUSPENDED SOLIDS DATA AT SURFACE WITH 37 SECCHI DISC TRANSPARENCY - STATION 1 9A SECCHI DISC vs. PHYTOPLANKTON COUNTS - STATION 1 38 10 DIAGRAM OF ISOPLETHS OF DISSOLVED OXYGEN - STATION 1 39 11 TOTAL IRON - STATION 1 54 12 TOTAL MANGANESE - STATION 1 ' 55 13 SURFACE CONCENTRATIONS OF AMMONIA NITROGEN, NITRATE 57 NITROGEN AND TOTAL PHOSPHORUS - STATION 1 14 HYPOLIMNION CONCENTRATIONS OF AMMONIA- NITROGEN 58 NITRATE NITROGEN AND TOTAL PHOSPHORUS - STATION 1 15 TOTAL LIVE PHYTOPLANKTON - STATIONS 1 AND 2 68 16 SEASONAL VARIATIONS IN PHYTOPLANKTON - STATION 1 69 17 CHLOROPHYLL a. DATA - STATIONS 1 AND 2 70 18 DISTRIBUTION OF AQUATIC VEGETATION - JULY-AUGUST 1980 72 19 STORM DRAIN SYSTEM . " 78 A EUTROPHICATION - THE PROCESS OF AGING BY ECOLOGICAL SUCCESSION , • B DIAGRAMMATIC SKETCH SHOWING THERMAL CHARACTERISTICS OF 113 TEMPERATE LAKES C PREDICTED AND ACTUAL YIELDS OF SELENASTRUM CAPRICORNUTUM 122 GROWN IN SPY POND FOREWORD

The following report is a presentation and discussion of the water quality in Spy Pond. This report does not present or discuss any data pertaining to the nutrient budget, hydrologic budget, retention time or flushing rate. These areas will be covered in the feasibility portion of the study done by Environmental Design and Planning, Inc. This report, under a separate cover, is entitled "Feasibility Study of Lake Restoration in Spy Pond, Arlington." The diagnostic portion of the study as set forth here is basically comprised of background information and a current limnological description of the lake. "A lake is a landscape's most beautiful and expressive feature; it is earth?s eye on looking into which the beholder measures the depth of his own nature."

Henry David Thoreau "Walden" 1854 INTRODUCTION

Purpose of Study

This report summarizes the information obtained during a diagnostic study of Spy Pond in Arlington, Massachusetts, conducted by the Commonwealth of Massachusetts, Department of Environmental Quality Engineering, Division of Water Pollution Control from March 1980 to April 1981. The purpose of the diagnostic study was to estimate and characterize the pond's current limnological condition by examining both the lake and its watershed. The survey provided data for the state's lake classification and restoration/ preservation program and fulfilled the requirements of Section 314 of the 1977 Amendments to the Federal Water Pollution Control Act (PL95-217).

A report of the feasibility study of Spy Pond, conducted under contract with the Division of Water Pollution Control by Environmental Design and Planning, Inc., of Allston, Massachusetts from October 1981 to September 1982, is presented under a separate cover.* This report presents and discusses data pertaining to stormwater runoff, and nutrient and hydrologic budgets that were closely examined as a result of the diagnostic study. It also discusses cost- effective solutions for permanently improving and enhancing water quality in Spy Pond. Background and History

Spy Pond (42° 24' 30"N, 71° 9* 19" W) is a 41.3 hectare (102 acres) lake located in the southern end of the town of Arlington, about 12.9 kilometers (8 miles) northwest of Boston. The 350 hectare (864 acres) watershed is divided between the towns of Arlington and Belmont, which contain 73% and 27% of the area, respectively. State Route 2 borders the southwest shore of Spy Pond and forms the division between Arlington and Belmont.

There are a total of forty-three known drains which empty into Spy Pond. All but two or possibly three of these deliver urban storm water to the lake whenever it rains. Such urban storm water carries a rich supply of pollutants derived from urban litter. The nature of this material has been described by Lazaro (1979) as follows:

"Litter includes remnants resulting from careless public and private waste collection operations, animal and bird droppings, soil washed or eroded from land surfaces, construction debris, road surfacing materials ravelled by travel, impact, frost action or other causes, air pollution dust falls, windblown dirt from open areas and a host of subsidiary materials."

* Final Report: Environmental Design and Planning, Inc. December 1982. Feasibility Study of Lake Restoration in Spy Pond, Arlington. Stonnwater problems develop and expand with the urbanization of an area. Thus the slow degradation of Spy Pond's water quality no doubt paralleled the slow but steady development of the Arlington and Belmont communities. For this reason, a brief historical sketch of the area surrounding Spy Pond is included in this report.*

Originally part of Cambridge, the area comprising Arlington was first set off as a distinct precinct in 1732. In 1762 this second parish of Cambridge was incorporated into a district known as Menotomy, because it was located on the western side of the Menotomy River (now known as Alewife Brook). In 1807 an act was passed by the state legislature to divide the town of Cambridge and incorporate the westerly parish (Menotomy) as West Cambridge. The name was again changed in 1867 to Arlington by the State Legislature.

In the 1870's, the chief industry in Arlington was apparently gardening. The north and east shores of Spy Pond and many acres along Pleasant Street were used extensively for vegetable gardens. By 1907 it is said that Arlington was the number one market garden town in the country. All of this land used for gardening adjacent to the lake was apparently heavily fertilized because the original soil was not suitable for farming (Common- wealth of Massachusetts, 1953).

Any impact of this agricultural activity on the water quality of Spy Pond was not reported in the available literature. All descriptions of Spy Pond compliment the beauty of the waterbody. It is likely that during the long period of intensive garden fanning (a span of about 100-150 years) sediment and nutrients were steadily increasing in Spy Pond and that only beginning in the late 1800's and early 1900's'did weed growth become noticeable. The photographs from this period in Spy Pond Stories (Balazs, 1973) show thick weed growth around Elizabeth Island.

Another major activity which occurred on Spy Pond in the mid 1800's was ice harvesting. It was this business as well as the demand for Arlington's garden produce that brought the railroad up from Fresh Pond to Spy Pond and then on to Lexington.

Both the produce farms and ice business declined around the late 1800's. Extensive development of Spy Pond's watershed began during this period. The larger farms surrounding the pond were broken up into building lots and access roads were constructed.

Spy Pond was apparently never used as a drinking water source for any length of time. Chapter 13 of the Acts of 1855 showed that the Spy Pond Water Company was incorporated for the purpose of providing water to the people of Arlington. However, by 1898 problems forced the town to abandon its

* The following historical sketch, except where specifically noted, is based on Cutter, Benjamin and William R., History of the Town of Arling- _tp_n,__Massachusetts. David Clapp and Son, Boston, 1880, and also Parker, Charles S. Town of Arlington - Past and Present. C.S. Parker and Son, Arlington, Massachusetts, 1907. attempts to implement a local water works system and they joined the Metropolitan Distric Commission.

The above review of Arlington's history shows clearly that the lake was once the focal point for the town's activities, both recreational and economical. There is no doubt that public use and enjoyment of Spy Pond has dramatically declined in recent years. With the recent sharp increase in the cost of fuel and travelj public use of local resources is likely to increase. Should the water quality of Spy Pond be successfully restored, the popularity of the lake for recreation may return.

Spy Pond has been the subject of several water quality studies in its recent past. Most of these studies were authorized and funded by the State Legis- lature. Such studies, carried out by the Metropolitan District Commission, occurred in 1950, 1952, 1953, 1954, 1955, and 1957. The 1952 investigation into the sanitary condition of Spy Pond was a thorough water quality study. The results of this particular project were printed as House Document No. 2208 in 1953 and offer an excellent basis for comparison with the present diagnostic study. A data comparison will be described later in this publication.

Other investigations into the water quality of Spy Pond include those of Habitat (1972) and Cortell (1973). The Cortell report contains historical data on the phytoplankton, macrophyton, and the various algicides and herbi- cides used for their control.

10 WATERSHED CHARACTERISTICS

Physical Description

Location and Topography

The Spy Pond watershed lies in a southwestern section of the Mystic River Basin within the towns of Arlington and Belmont (See Figure 1). It covers a total area of 350 hectares (864 acres), 254 hectares (627) acres of which lie in Arlington and 96 hectares (237 acres) of which are located in Belmont. Despite the small size of the watershed it is contrasted by rather steep hillsides to the west-northwest (Arlington Heights) and somewhat flat terrain to the east and southeast. The highest elevation of 370 feet above mean sea level (MSL) (Boston base) is in the northwest corner where a Metropolitan Distric Commission water tower is located. The eastern and southern areas of the watershed average only about ten feet above MSL while the lake itself is four feet above MSL.

The western elevation has a fairly steep rise but is nevertheless almost completely developed. It is on this hillside that the .only undeveloped area is located - the Menotomy Rocks Park. There is a small pond located within this park which drains into Spy Pond via the nearby state Route 2 drainage system. As a consequence of the fairly steep grade on the western side the stormwater runoff occurs very rapidly, especially along the Route 2 drainage system.

In the seventeenth century most of the area to the south of Spy Pond was wetland. The so-called "Great Swamp" stretched along the banks ofMenotomy River (Alewife Brook) and south of the lake. It has taken many generations to turn this area into usable land, but enough of the swamp remains to help one envisage what it must have been like several hundred years ago.

Geology*

Spy Pond is located within an area known as the "Fresh Pond Buried Valley." This is a deep sediment-filled bedrock valley that extends from the town of Wilmington southeastward to Boston Harbor. It underlies Mishawum Lake, Woburn; Wedge Pond, Winchester; the Mystic Lakes, Winchester and Arlington; Spy Pond and Fresh Pond, Cambridge; and the Aberjona River. A thin, dis- continuous layer of till covers the highlands bordering Che buried valley while stratified deposits predominate in the valley itself. Spy Pond is located just west of the central axis of the buried valley. Rock outcrops

* Largely based upon Chute, Newton, E. Glacial Geology of the Mystic Lakes - Fresh Pond Area, Massachusetts. Geological Survey Bulletin 1061-F, United States Printing Office, Washington, D.C., 1959.

11 IS)

200

Watershed Boundary Menotomy Rocks Park Boundary Municipal Boundary Elevation in Feet 60 DEQE/DWPC T.ehilctl Strvlcn Branch J C FIGURE 1 GENERAL WATERSHED MAP occur only along its margins. Igneous outcrops are common to the northwest of the lake, especially on the side of the steep gradient and within Menotomy Rocks Park.

As the glacial ice recreated, advanced, and retreated again, sand, gravel, and clay were deposited in varying proportions throughout the valley. A large lowland area between the Mystic Lakes and Fresh Pond (which is located in Cambridge about one mile south of Spy Pond) was at one time during this sequence, a lake or possibly a marine embayment. During the time of this lake's existence clay was deposited over the area. Then, with further retreat of the glacial ice northward, an alluvial fan of outwash material (chiefly sand and gravel) was deposited over the area. It was during this period that ice blocks occupied the present lake basins, including Spy Pond. Late glacial streams then eroded the valleys in which the present streams exist. The ice blocks were probably still present at this time, otherwise these basins would have been filled in by the post-glacial streams. Thus Spy Pond, as well as the other ponds in the valley, can be classified as kettle holes, which is the term given to those lakes formed by the melting of giant ice blocks.

Soils*

The soils within the Spy Pond watershed were formed from materials influenced by glaciation. There are two basic soil associations in the watershed (see Figure 2). The steep hills and uplands to the west are composed predominately of the Paxton-Hollis-Canton association. These are well drained soils developed in stony glacial till derived largely from schist, gneiss, or closely related granitic material. The surface soil, subsoil, and substratum are generally a fine sandy loam. The Paxton soils, making up to 50% of the association have a loamy, slowly permeable substrata; the shallow to bedrock Hollis soils constitute about 15%; and Canton soils with their sandy permeable substrata make up about 10% of this association; the remaining 25% consists of numerous minor soils.

The depth to bedrock or hardpan is generally within two or more feet of the surface. Bedrock outcrops are frequent and these soils are stony below the surface. The Paxton-Hollis-Canton association soils are well drained. However, the shallow bedrock that exists on the western slopes of the watershed must have caused some sub-surface disposal problems prior to installation of the area-wide sewerage system in 1895 (U.S. EPA, 1978).

The soil of the eastern and southern section of the lakes' watershed is composed primarily of sand and gravel, and possesses good drainage characteristics. This soil was deposited by the glacial stream as outwash material. The depth to bedrock along the eastern shore of Spy Pond is about 150 feet

* Based on U.S. Dept. of Agriculture, Water and^_Rela/ted_ Land Resources of the Coastal Region - Massachusetts- 1978; and Chute, Newton E., Glacial geology of the Mystic Lakes - Fresh Pond Area. Geological Survey Bulletin 1061-F, United States Government Printing Office, Washington, D.C., 1959.

13 •J < V if X ."...'-..' ,.'. ' . ' -.'..•-. • > X • • '•

>^v<-C>X'->v\'-Xv<\'.-vv.'-.-,;.,V>6'x"X^.v

WVVP'.VVW » - - - ", " » • «. -. -v/x,"^ ^_ - VWA ' * w A *, v, • ,\ •, v^XvwX

v ^SMM'ft^ *• y *. .* " ,*s • " *. . . ^ .- . s MA- h , v v w

Paxton-Hollis-Canton Association Muck and Swamp Deposits

Sand and Gravel Artificial Fill K/ Watershed Boundary —

DEQE/DWPC Ticbnfeil Sirvfcts Brcneli

FIGURE 2 GENERAL SOILS MAP faelow mean sea level (Boston base).

There is also a small area of muck (swamp deposits) located along the southern shore of Spy Pond, This area is easily found since it is colonized by a large stand of Phragmites sp. (reed grass).

Climatology*

The climate of the Spy Pond watershed is typical of the coastal region of Massachusetts, The average annual temperature is approximately 10 C (50 F) with an average in January of about -1.1 C (30 F) and a July average of about 21.7 C (71 F) , Mean annual precipitation is about 11.2 cm (44 inches). The average snowfall is about 1.3 m (50 inches). The average annual runoff is over 50% of the average annual precipitation. Historically, major storms and floods have occurred during nearly every month of the year.

Hydrology

The total area of Spy Pond's watershed encompasses 350 hectares (964 acres) with Spy Pond occupying 41.3 hectares (102 acres) of that area. The entire watershed of the lake, with the partial exclusion of Menotomy Rocks Park, is serviced by a stormwater collection system which empties into the lake. There are a total of 43 pipes emptying into Spy Pond (see Figure 3). _ Forty of these have been identified as municipal storm drains.

The storm drain system, divided into four areas for descriptive purposes, can be described as follows: (also see Figure 3A)

1) The largest single area is the Route 2 drainage area. This system includes Route 2, the Belmont section of the watershed, Menotomy Rocks Park, and all of that area above and immediately below the park. All of this area enters the Route 2 drainage system through lateral pipes and enters the southwest corner of Spy Pond by way of a 13.7 cm (54 inches) pipe. This concrete culvert, considered the inlet for Spy Pond, was the only source in the lake with a constant base flow. During major storms the volume and rate of flow has been very great, and for this reason several stone pillars were placed in front of the culvert during recon- struction of Route 2 to serve as energy dissipators.

2) A second drainage collection system is located along the northwest side of the lake. This system includes the drainage area above and below Pleasant Street and enters the lake through several storm drains located at the ends of the side streets. It also includes the area surrounding the Arlington Boy's Club.

3) The third area includes the Massachusetts Avenue corridor and all of.its side streets within the watershed. This system drains the eastern area and enters the lake predominantly through a drain located at the end of Pond Lane and several drains located in the corner of the eastern bay.

*Information from U.S. Dept. of Agriculture, Water and Related Land Resources of the Coastal Region - Massachusetts, 1978.

15 LEGEND

• Storm Drain

© Storm Drain Sample Site

* Wet Weather Sample Site GEGE- QwPC- Technical Services

FIGURE 3 LOCATION OF STORM DRAINS Suli-Urninaye An;a Boundary Elevation in Feet

Slnrm Drains Watershed Boundary

DEQE/DWPC Technical Servlcvi Branch

WATERSHED STORM DRAIN SYSTEM AREAS 4) The fourth area of drainage includes the land north of Lake Street and west of the railroad tracks in the southern portion of the watershed. The stormwater draining from this zone enters the lake mainly via two pipes found in or near the southernmost corner of the lake.

The outlet from Spy Pond is a concrete rectangular standpipe located in the southeastern corner. From the standpipe, Spy Pond's overflow enters a large culvert and flows about 300-325 m underground beneath state Route 2 where it enters Little Pond. From here the water flows east and then north as Alewife Brook, joining the Mystic River at the junction of the Arlington, Medford, and Somerville town lines.

Development

Land Use

The entire watershed of Spy Pond is densely developed except for 11.9 hectares (29.5 acres) within Menotomy Rocks Park. The major land use is residential single family housing. Figure 4 shows the distribution of land use within the watershed. Apartment houses are found along portions of Pleasant Street, Massachusetts Avenue, and adjacent to the lake next to park property. Pleasant Street and Massachusetts Avenue are also zoned for commercial use. The Plea- sant Street businesses are restricted to small neighborhood offices, whereas Massachusetts Avenue, historically, has acted as the commercial strip for the town of Arlington,

The land use pattern within the Spy Pond watershed is not likely to change significantly in the future. The potential for increases in apartment housing and office space appears to be confined to the main streets of Massachusetts Avenue and Pleasant Street.

There is no significant industrial water use within the Spy Pond watershed. The town landfill, which was closed in 1969, was located outside the watershed. Road salt is stored by Arlington's Department of Public Works at the town yard on Gove Street, but this is also outside of the watershed. There is no longer any agricultural activity in the watershed, nor any area of intensive development or construction.

No known individual subsurface disposal systems operate within the pond's watershed. The entire area is serviced by the Metropolitan Sewer District (MSD) with treatment provided by the Deer Island Facility. According to a report by the Metropolitan Area Planning Council (MAPC) (Area Wide Waste Treatment Management Plan, 208 Report, Part I, Volume II, 1978) (Draft), there are no known overflows or bypasses from the Arlington sewer system.

The Arlington Department of Public Works is responsible for maintenance of Arlington's stormwater collection system. The catch basins are currently cleaned twice a year (Metropolitan Area Planning Council Report, 1977), but the town is considering a change to one cleaning per year for all catch basins except drains in problem areas. Considering the character of land use and the extensive drainage system entering into Spy Pond it is apparent that the pond's water quality is adversely influenced primarily by nonpoint sources of pollution from urban stormwater runoff.

18 CO

Boston & Milne Railrcad Private Open Public Open

Single Family Predominant I Public Building

Two Family Predominant Watershed Boundary DEQE/OWPC Technical Strvlcti Branch

FIGURE 4 GENERAL LAND USE A study of urban runoff by Mance and Herman (1978) presented the following conclusions:

1. Run-off from a purely residential area is of poor quality and carries a significant pollutant load; particularly note- worthy are the mean concentration of suspended solids and the maximum concentrations observed for ammoniacal nitrogen, chloride, and heavy metals.

2. Snow-melt run-off is of much poorer quality than rainfall run-off because of road-salting operations, less efficient performance of the internal combustion engine 'in the cold at low speeds, and contamination of the snow by direct contact with the underside of vehicles.

3. A "first flush" (i.e. occurrence of the peak concentration within the first 40 minutes of discharge) was observed in 80 percent of the events studied.

4. The flow-weighted mean concentrations of pollutants in the run-off decreased with the increasing duration of discharge but had not decreased by more than 40 percent even after 100 minutes of discharge.

5. The length of the antecedent dry period and the magnitude of the previous run-off event have little effect on the quantity of pollutants discharged.

6. Most of the particulate solids in run-off originate on roads and paved areas.

7. Roof run-off makes a negligible contribution to the pollutant load of run-off and has a diluting effect on road run-off.

8. Road drain catchpits represent a significant reservoir of poor quality water, the behavior of which is difficult to predict.

9. Flushing of road drain catchpits during rainfall can contribute significantly to the pollutant load of run-off.

After a rain, the first flush of water into Spy Pond through the storm drain pipes contains v isable concentrations of suspended and dissolved solids. Large' sand deltas that built up in front of most of the storm drain outlets also attest the severity of urban runoff into Spy Pond.

20 Population

Table 1 illustrates changes and projections for the population of the town of Arlington: TABLE 1

PERCENT YEAR. POPULATION CHANGE

1950J 44,353 1960J 49,953 12.6 1965" 52,482 5.1 19701 53,524 2.1 19752 50,223 -6.3 19801 48,219 -4.0 19902 49,500 (projected) 2.6 (proj ected) 20002 51,000 (projected) 3.0 (projected)

U.S. Census of Population, 1970, 1980 2 State Census, Department of Commerce and Development, 1978.

Since 1960 the population of the area has not drastically changed, nor is it projected to change much by the year 2000.

The median income for an Arlington family in 1970 was $12,247. Those below the poverty level constituted 4.1% of the families while those earning $15,000 or more made up 32.6% of the families.

A report by the town of Arlington (Arlington Redevelopment Board, 1973) found the economic climate of the area in a state of flux and not very encouraging. They found "strong indications of underlying stagnation" which they believed was directly linked to the land use in the town.

There are very few fresh water-based recreational sites available in this area. The Mystic lakes, less than two miles to the north, have severely degraded water quality. Despite this the MDC maintains a public beach on Upper Mystic Lake. Fresh Pond is about one and one-half miles to the south in Cambridge but is protected as a drinking water supply. There is also a small body of water known as the Arlington Reservoir located on the town line in the northeast corner of Arlington. The water quality of this pond is degraded but the town is currently studying means of improving the wa'ter quality for recreation. Although a swimming area for town residents is maintained at this pond, it has recently experienced reduced use due to water quality problems.

For the residents of this area there is no lake within easy commuting distance which offers clean water quality and a full range of water-based recreation.

21 The census data indicates that a potentially large lake user population exists in Arlington and the surrounding communities. The five neighboring communities of Arlington, Medford, Somerville, Cambridge and Belmont had a 1980 population of 305,089 (U.S. Census Bureau, 1980). However, present use of the area is only moderate due to the degraded water quality of Spy Pond.

22 LAKE CHARACTERISTICS

Morphemetry

A bathymetric map of Spy Pond (Figure 5) was provided by the Massachusetts Division of Fisheries and Wildlife and confirmed in the field on November 25, 1980 using a fathometer (Ray Jefferson Fish Flasher 6006). Configuration, shore line development, and area of the lake were determined from a United States Geological Survey topographic map (Lexington, Massachusetts, 1971 quadrangle, 7.5 minute series) utilizing a planimeter and a rotometer according to Hutchinson (1957) and Welch (1948). The morphometric data presented in Table 2 were derived from these maps.

The southwest basin is considerably shallower than the northwest basin. On the western side of the southern basin a pile of rocks, just below the surface, poses a hazard to motor boaters.

Lake Uses

The Arlington's Boys Club, located on the northern shore, is the only organized group that uses Spy Pond on a regular basis during the summer. The club maintains several small sail boats, but sailing activities are restricted to the northeast basin due to dense aquatic weed growth in the shallow southwest basin,

Swimming, once popular in Spy Pond, is minimal even on hot days. Recently, a pool was constructed within the Boys Club grounds to avoid using the lake for swimming.

Fishing at Spy Pond is minimal. Historically, the Massachusetts Division of Fisheries and Wildlife has stocked the lake with warm water fish species.* In 1957 the pond was reclaimed and stocked with largemouth black bass (Micropte- _rus salmo_id_es Lacepede), brown bullhead (Ictalurus nebulosus LaSueur), and yellow perch (Perca flavescens Mitchill). A 1980 survey by the Division of Fisheries and Wildlife found the following species of fish present in Spy Pond(listed in order of abundance) white perch (Roccus americanus Graelin), largemouth black bass, golden shiner (NotemigQnus crysoleucas Mitchill) yellow perch, bluegill (Lepomis macrochirus Rafinesque), alewife (Alosa pseudoharengus Wilson), american eel (Anguilla rcasjtrajia LeSueur), brown bullhead, pumpkinseed (L,e£oinis gibbosus Linnaeus), and gold fish (Carrassius auratus Linnaeus). In September of 1980 the Division stocked the pond with 700 tiger muskies (Esox liicius_ X Esox masq^uinongy hybrid) in an attempt to control the forage fish populations.**

Public access to Spy Pond is available from Linwood Street off Route 2A or Pond Lane on the northwestern side of the lake. A public park with parking facilities accessed via Pond Lane borders the northeastern shore of Spy Pond.

* Massachusetts Division of Fisheries and Wildlife, Westborough, Massachusetts. Files on Spy Pond, Arlington A*Personal communication, Nov. 3, 1982, Peter Jackson, Massachusetts Division of Fisheries and Wildlife, Northeast District, Acton, Massachusetts.

23 mile 1/4

Inlet

Depth in Meters

Outlet I\ Sampling Station

SPY POND BATHYMETRY and FIGURE 5 LOCATION OF SAMPLING STATIONS

24 TABLE 2 SPY POND MORPHOMETRIC DATA

Maximum Length 1,128 meters (3,700 feet) Maximum Effective Length 1,128 meters (3,700 feet) Maximum Width 792 meters (2,600 feet) Maximum Effective Width 792 meters (2,600 feet) Maximum Depth 11.5 meters (38 feet) Mean Depth 4.4 meters (14 feet) Mean Width 366 meters (1,200 feet) Area 41.3 hectares (102 acres) Volume 1,795 x 103 meters3 (6,339X104ft3) Shoreline 3,505 meters (2.2 miles) Development of Shoreline 1.54 Development of Volume 1.1 Mean to Maximum Depth Ratio 0.38 Drainage Area 349.R hectares (864 acres) Elizabeth Island 1.05 hectares (2-6 acres)

25 The park, is equipped with playground facilities, a ball field, and a swimming area.

There is no formal boat launch ramp or dock for public use on the lake, but small boats can be launched from the shore near the swimming area. A strip of public land borders the southern shore along State Route 2 and provides access to the lake only by foot.

Historically, Spy Pond was a popular area for recreation, but is now largely ignored. If the water quality in the pond were sufficiently improved to allow public swimming the lake would once again become an asset to the community.

26 LIMNOLOGICAL DATA

Methods

Sampling Stations

The sampling program for collection of water quality data for Spy Pond was conducted from March 1980 to April 1981. Survey dates, together with the stations sampled at each time are presented in Table 3.

The locations of the sampling stations can be found.on the bathymetric map (Figure 5). There were two in-lake water quality stations established on Spy Pond. Station 1 was located in the northern basin over the deepest (11 m) portion of the lake. Station 2 was established as the deep hole (6 m), open water station in the southern basin.

Station 3 in the southwest corner of the lake was located at what was considered the inlet for Spy Pond. This inlet, described previously, was the only source into Spy Pond with a constant base flow.

Station 4 was established at the outlet of Spy Pond approximately 250 m southeast of the inlet culvert (Station 3).

Physical, Chemical and Bacteriological Methods

Temperature profiles were made at the lake using a Tele-Thermometer (YS1 model 42 Sc). Transparency measurements were made with a 20 cm Secchi disc following standard procedures described in Hutchinson (1957). Field pH readings were taken with a Hach Model 17N Wide Range pH test kit.

Chemical and bacteriological analysis were performed in samples from the inlets, the outlets and the two open water stations. The deep water samples were collected with a standard brass Kemmerer water sampler. The inlet and outlet surface samples were collected by hand after thoroughly rinsing the sample bottles. Bacteriological samples were collected at the surface by hand in sterilized, screw-capped glass bottles. In addition to the four regularly sampled stations, 21 samples for bacteriological analysis were collected on four days during August, September,and October of 1980, This additional sampling was performed to monitor the sanitary condition of the water in areas likely to be frequented by the public or impacted by the storm drains. The locations of the 14 sampling stations are shown in Figure 6. Stations A and E were located in swimming areas. Station N was sampled near the Boy's Club dock and Station G was located in front of the inlet. The remaining stations were located a few meters in front of storm drain outlets.

All samples for chemical and bacteriological analyses,were packed in ice and transported the same day to the Lawrence Experiment Station of the Department of Environmental Quality Engineering, Division of Laboratories, and analyzed according to Standard Methods for the.Examination o_fWater arid Was^ewater .(APHA, 1976);and Methods for Chemical Analysis of Water and Wastes (U.S. EPA, 1979).

27 TABLE 3 SPY POND WATER QUALITY SAMPLING PROGRAM

SAMPLING STATION 1 STATION 2 RT.2 INLET OUTLET DATE D.O./TEMP. CHEM. D.O./TEMP. CHEM. CHEM. CHEM.

3/12/80 X X 3/20/80 X X X X X 3/24/80 X X X X X 4/1/80 X X X X 4/9/80 X X X X X 4/14/80 X X 4/22/80 X X 4/28/80 X X 5/8/80 • X X 5/12/80 X X X X X 5/19/80 X X 5/27/80 X X X X X 6/3/80 X X 7/1/80 X X X X X 7/7/80 X X X X X 7/14/80 X X X X X 7/21/80 X X X X X 7/28/80 X X X X X 8/4/80 X X X X X 8/11/80 X X X X X 8/18/80 X X X X X 8/25/80 X X X X X 9/22/80 X X X X X 10/23/80 X X X X X 10/29/80 X X X ' X X 11/13/80 X .X X X X 1/13/81 X X X 2/11/81 X 2/18/81 X X 2/25/81 X X X X X 3/19/81 X X X X X 4/6/81 X

X = data collected 28 LEGEND

• Storm Drain

A. Sanitary Survey Station

1OEQE • DWPC- Technical Services Branch

FIGURE 6 LOCATION OF SANITARY SURVEY STATIONS

29 The following analyses were conducted on the samples: pH, total alkalinity, total hardness, specific conductance, chloride, suspended solids, total solids, total Kjeldahl-nitrogen, ammonia-nitrogen, nitrate-nitrogen, total phosphorus, total iron, total manganese, total and fecal coliform and fecal streptococcus bacteria

Dissolved oxygen samples were collected according to Welch (1948). Samples were fixed in the field with manganese sulfate and alkali-azide-iodide reagents and titrated soon afterwards. Sulfuric acid was added just prior to the titrations in the laboratory. Dissolved oxygen concentrations were determined by the azide modification of the Winkler technique.

Phytoplankton and Chlorophyll £

Samples were collected from Stations 1 and 2 following a standard procedure described by the Maine Department of Environmental Protection, Division of Lakes and Biological Studies (1974). During unstratified periods the samples were collected just under the surface of the water. If the lake was stratified a composite core sample of the epilimnion was taken with a 0.63 cm I.D. plastic tube. All samples were collected in clean, rinsed glass sample bottlest

Samples were analyzed for phytoplankton soon after collection using a Whipple micrometer and Sedgewick-Rafter counting cell. Counts were reported as cells of algae per ml (Prescott, 1954;and Smith, 1950).

Chlorophyll a. analysis (Appendix A) was based on methodology from a modified U.S. EPA" fluorometric procedure developed by the Division of Water Pollution Control at Westborough (Kimball, 1979).

Aquatic Macrophyton

During early April of 1980 before macrophyte growth, a visual survey of Spy Pond's littoral zone was conducted by boat to assess substrate characteristics. During July and August of 1980 a careful visual inspection of the littoral zone of the lake was conducted to locate and map the aquatic vegetation. In deep water,plants were collected by dragging a grappling hook over the substrate; otherwise representative macrophytes were collected by hand. Identification was made in the field or if necessary, entire plants were taken back to the lab for analysis. Identification of the plant speci- mens were made using a stereoscopic microscope and several taxonomic keys (Fassett, 1957; Hotchkiss, 1972; and Prescott, 1969).

Storm Drainage Sampling

The storm drains emptying into Spy Pond were visually inspected;and their size, type, and condition recorded. The storm drainage systems in the watershed were determined from a United States Geological Survey topographical map (Lexington, Massachusetts, 1971 Quadrangle, 7.5 minute series), a description of the stormwater discharges to Spy Pond prepared by a Department of Environ- mental Quality Engineering student intern in 1980 and maps of che storm sewers for the towns of Belmont and Arlington.

During the sampling period from March, 1980 to February, 1981 the discharges into Spy Pond from 20 storm drains were sampled occasionally. The locations of the storm drains around Spy Pond are shown in Figure 3 and the storm drains that were sampled are noted.

30 A wet weather survey of the drains marked with an asterisk on Figure 3 was conducted on July 23, 1980. Sampling took place during the period of initial discharge through the pipes. These drains were sampled because they served a large drainage area and previous observations had noted substantial flows during wet weather. Chemical and bacteriological analysis were performed on these samples as previously described.

The storm drain sampling was performed to quantitatively assess the storm drain discharges and to identify those drains that contribute the largest pollution load to the lake.

31 Results

Physical

Temperature

Temperature profiles at Spy Pond were characteristic of temperate dimictic lakes. A depth-time diagram of isotherms compiled from.temperature data taken at Station 1 from March, 1980 - April, 1981 shows that thermal stratification at Spy Pond began in early April, 1980 and was well established by early May. The thermocline began to erode in August and by the end of October the pond'had undergone fall turnover (see Figure 7).

The period of winter ice cover on Spy Pond during the 1980-1981 season was relatively short. A continual ice cover was maintained from mid-December to mid-February. Ice out, which usually occurs in March, took place in early February. During the January, 1981 survey there was 30.5 cm (12 inches) of ice on the lake. At this time the lake was inversely stratified with water temperatures of 4.0 C to 4.5 C. Following ice out in February, the temperature of the water column was nearly identical with that of the January survey. By the mid-March survey the lake was undergoing complete circulation. Water temperatures were one degree colder than those during ice cover and reflected the cold weather experienced in late February and early March.

The water column at Station 2 was also thermally stratified with the thermocline located at three to four meters during the summer. Fall turnover occurred about one week earlier at Station 2 than Station 1 due to the shallow- ness of the basin.

A complete record of temperature data collected for Stations 1 and 2 is presented, together with dissolved oxygen and percent saturation data, in Appendix B, Tables I and II.

Secchi _D_is_c_transparency

Secchi disc measurements quickly assess the transparency of water, and are influenced by weather conditions, wave action, time of day, plankton densities, suspended materials, and water color. The Secchi disc readings for Stations 1 and 2 are presented in Table 4 with time of measurement, weather and surface water conditions.

Figure 8 compares the readings from Stations 1 and. 2. From mid-June to mid- August and again in October and November, the Secchi disc transparency of the water was below the state's minimum value recommended for public bathing of 1.2 m (Department of Public Health, Article 7, Regulation 10.213 of the Massachusetts Sanitary Code, 1969). The lowest reading of 0.7 m occurred on consecutive surveys in July at Station 2. The lowest reading at Station 1

32 1-

2- 10

3- •

4- • FIGURE 7

DEPTH/TIME 5" ISOTHERMS (°C) AT STATION 1

7- •

10 HH-H- 41 9 12 27' 14 28 II 25 22 231' 13 13 25' 19 7 21 4 18 29 Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Jan. Fell. Mar. Apr. 7980 1981 . TABLE 4 SPY POND SECCHI DISC TRANSPARENCIES (meters)

TIME* WATER DATE STATION 1 STATION 2 (hr) WEATHER CONDITIONS 3/20/80 2.1 1307; hazy sun choppy — 3/24/80 2.1 1.8 0930; 1100 sunny ripples 4/1/80 1.7 1.5 1230; 1200 sunny ripples 4/9/80 1.6 1.5 1045; 1130 cloudy choppy- 4/14/80 1.5 1.7 1215; 1130 cloudy choppy 5/12/80 1.8 1.6 1100; 1200 sunny calm 5/19/80 1.8 1.7 1200; 1130 hazy sun rough 5/27/80 1.4 1.3 1100; 1200 sunny rough 7/1/80 1.1 1.0 1030; 1130 cloudy calm 7/7/80 0.9 0.7 1100; 1200 sunny choppy 7/14/80 0.8 0.7 1045; 1130 sunny calm 7/21/80 1.0 0.9 1040; 1140 sunny calm 7/28/80 1.2 1.0 1230; 1300 sunny rough 8/4/80 1.2 1.2 1010; 1115 sunny calm 8/11/80 1.2 1.1 1045; 1145 c.loudy calm 8/18/80 1.4 1.2 1030; 1305 cloudy calm 8/25/80 1.8 1.2 1030; 1130 sunny calm 9/22/80 1.6 1.4 1030; 1200 sunny choppy 10/23/80 1.0 0.8 1038; 1125 sunny ripples 10/29/80 1.2 1.0 1100; 1145 sunny rough 11/13/80 1.2 1.2 1015; 1115 sunny choppy 11/25/80 1.8 1015; cloudy calm — 1/13/81 1.4 1045; cloudy 12 -inch ice — 2/25/81 1.2 1.2 1130; 1230 cloudy, w/rain choppy 3/19/81 1.6 1.5 1100; 1130 sunny calm 4/6/81 1.5 1030; cloudy rough —

*Times are sequential for stations. r FIGURE 8 SECCHI DISC TRANSPARENCY AT STATIONS 1 AND 2

2.0-r

1.8- •

STATION 1

M1NIMUM STANDARD 1.2 FOB STATE PUBLIC BATHING AREAS

o STATION 2—\ .' 5 ••••

0.4-

Ht-H—I—H—ri li i | i il i I I'll H i-H—\ •t—t-t 24'l 914 12.1 27 7 J.2 IJn4 .Lisj8. , 22 23,' II 25 13 25 19 20 t

Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Jan. Feb. Mar. Apr. 1980 1981 was 0.8 m,observed on July 14.

The concentration of suspended solids did not always support the trends in water transparency. It has generally been found that the greater the concentration of suspended solids, the lower the Secchi disc transparency will be (Wetzel, 1975). Figure 9 illustrates that this inverse relationship at Spy Pond was observed only during May and June.

Comparison of phytoplankton counts with transparency (see Figure 9A) demonstrate that at Spy Pond the algal concentrations were probably most influen- tial in reducing the Secchi disc visibility at Station 1. The two major ' phytoplankton peaks in July and November occurred concurrently with reduc- tions in water transparency.

Chemical Data

Dissolved Oxygen

The concentration of dissolved oxygen is an important indicator of the biological processes occurring in a lake system. Oxygen is an end product of phytosynthesis, and can therefore be increased by autochthonous plant activity. Atmospheric oxygen also diffuses into the lake at the surface and is mixed into the water column as wind and wave action circulate the water. The concentration of dissolved oxygen in the bottom water is affected by mixing of the surface waters with deeper waters and by biological and chemical oxygen demand created by active respiration-decomposition in the sediments. The level of oxygen concentration in the water column determines the kinds of aquatic organisms that can exist in the lake.

Figure 10 illustrates the concentration of oxygen throughout the water column of Spy Pond at Station 1 for the duration of the study. After thermal stratification was established in April, (1980) anaerobic conditions occurred rapidly in the hypolimnion. By the end of May the oxygen profile of Spy Pond was typical of eutrophic lakes. The bottom was completely anoxic and the epilimnion exhibited super saturated oxygen levels indicative of high algal production. Spring phytoplankton counts supported these data.

A complete record of dissolved oxygen concentration and percent saturation values of oxygen along with water temperatures at Stations 1 and 2 can be found in Appendix B, Tables I and II. The dissolved oxygen concentration in the surface waters of Spy Pond at Station 1 ranged from a low of 6.9 mg/1 (61% saturation) in late October to a high of 13.5 mg/1 (116% saturation) in April. The epilimnion was supersaturated with oxygen from April through most of August due mainly to high productivity. A drop in dissolved oxygen concentrations and percent saturation on August 11 was reflective of a decline in algal concentration.

The hypolimnion remained anoxic during the entire period of thermal stratification. Just prior to fall turnover the epilimnetic oxygen concentration was slightly over 7.0 mg/1 (66% - 68% saturation). This was considered

36 FIGURE 9 f SECCHI DISC TRANSPARENCY vs. SURFACE SUSPENDED SOLIDS AT STATION 1 -r!4

2.0-r-

+12

t.6+ +10

J >: 1-2

Irt a r- 5 6 ^

~ 0.8 +

0.4 +

SURFACE SUSPENDED SOLIDS + 2

I X 'I 20 9 12 27 23 13 2B 2' 4 23 13 19 I Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Jan. Feb. Mar. Apr. 1980 1981 FIGURE 9A SECCHI DISC TRANSPARENCY vs. PHYTOPLANKTON (cells/ml) AT STATION 1

2.0-r -T-1I1

1.6- -

u -1 X 1.2- D

11]

PIIYTOPLANKTON

UO.B CO

0.4-

•1 0' 24 9 12 27 22 __13 13 25 196 Mar. Apr. May June July Aug. Sept. Oct Nov. Dec, Jan. Feb. Mar. Apr. 1980 1981 f

12 12

FIGURE 10

ISOPLETHSOF .s 5 DISSOLVED OXYGEN (mg/l) 01 O AT STATION 1 8- •

I-

10 19 Nov. Dec. Feb. Mar. Apr. 1981 an unusually low oxygen level for a temperate deep lake at this time of year. After fall turnover, with the water column mixing completely, the dissolved oxygen level was at about 85% saturation, still lower than expected for well oxygenated New England lakes. This depressed oxygen level was most likely a result of the mixing, of anoxic water from the hypolimnion that contained a rich supply of organic matter and reduced inorganic chemical species that exerted a high oxygen demand on the entire water column.

A winter survey in January, conducted with 30.5 cm (12 inches) of ice on the lake, found dissolved oxygen concentrations of 9.2 mg/1 to 13.8 tng/1 (70% - 98% saturation). In February the minimum recorded concentration was 3.0 mg/1 (23% saturation) at ten meters. The concentration of dissolved oxygen down to nine meters was 6.0 mg/1 or greater. It is unlikely that the fish in Spy Pond were under any physiological stress due to low oxygen levels during the winter of 1980-1981. If ice cover had persisted for a longer period of time (e.g., a month or more) then the loss of oxygen might have been more severe as indicated by the rate of loss between January 13 and February 25 (see Figure 10).

JDH

The pH values measured in Spy Pond are presented in Tables 5 and 6 along^with the other chemical parameters. The pH values of the surface waters were always greater than 7.0 (Standard Units)and within the range for natural surface water (Hem, 1975). During July and August the pK of the surface waters at both stations became elevated (up to 9.5 at Station 1 on July 14) due co the nhotosynthetic activity of the phytoplankton. The lowest pH reading was 6.6, observed at Station 2 in September, 1980,

Total Alkalinity and Total Hardness

Alkalinity commonly results from carbon dioxide and rainwater (usually in the form of carbonic acid) weathering carbonate bearing rocks and dissolving out some of the carbonate to form bicarbonate solutions. A lake with carbonate-rich rocks in its watershed (for example, in the limestone area of the Berkshires) will have high alkalinity, whereas a lake with carbonate- poor strata in its watershed (for example, Cape Cod) will have low alkalinity.

The total alkalinity of a lake or pond determines its ability to withstand changes in pH, i.e. its buffering capacity, either from biotic or abiotic factors. A lake with very low total alkalinity will show daily and seasonal pH changes due to the addition of respiratory carbon dioxide or the removal of carbon dioxide via phytosynthesis. A well-buffered lake with high total alkalinity will not show significant pH changes under normal circumstances.

The total alkalinity content of lakes and ponds has taken on new signifi- cance in recent years due to the occurrence of acid deposition or acid rain as it is usually called. The pH of the rainwater in the Northeastern United States (and elsewhere) has been declining due to the formation of acids

40 TABLE 5 SPY POND RESULTS OF CHEMICAL ANALYSES (mg/1) STATION 1

3/20/80 3/24/80 4/1/80 4/9/80 5/12/80 PARAMETER 0.5m 10m 0.5m 6m 10m 0.5m 0.5m 10m 0.5m 10m pH (Standard Units) 7.5 7.5 7.3 7.3 7.3 7.8 7.8 7.6 7.7 7.1 Total Alkalinity 37 34 34 33 33 — 32 32 30 41 Total Hardness 62 62 62 62 62 — • 65 65 67 67 Conductivity (ymhos/cm) A70 470 480 470 470 — 490 500 460 500 Chlorides 115 116 114 116 116 115 120 118 130 110 Suspended Solids 7.5 8.0 2.0 0.5 1.0 3.0 0.0 0.0 — — Total Solids 304 300 294 288 284 — 358 354 348 294 Total Kjeldahl-N 0.60 0.59 0.51 0.73 0.56 1.1 1.2 1..1 0.60 1.2 Ammonia-Nitrogen 0.37 0.35 .0,36 0.39 0.38 0.22 0.17 0.24 0.04 0.82 Nitrate-Nitrogen 0.4 0.4 0.5 0.4 0.4 0.4 0.5 0.5 0.5 0.3 Total Phosphorus 0.04 0.03 0.01 0.02 0.01 0.03 0.05 0.04 0.04 0.11 Total Iron 0.04 0.00 0.06 0.03 0.04 — 0.00 0.04 0.07 0.06 Total Manganese 0.00 0.00 0.02 0.07 0.02 — 0.02 0.05 0.02 0.55 TABLE 5 (CONTINUED)

5/27/80 7/1/80 7/7/80 7/14/80 0.5m 5m 10m 0.5m 6m 10m 0.5m 5m 10m 0.5m 5m 10m PARAMETER

pH (Standard Units) 9.1 7.3 7.3 7.4 7.1 9.4 7.6 7.7 9.5 7.2 7.2 Total Alkalinity 40 32 44 43 36 53 31 34 57 30 35 57 Total Hardness 69 64 69 64 67 70 61 65 68 65 65 67 Conduc tivi ty (ymhos/cm) 440 440 450 470 480 530 465 480 520 470 470 520 -p- to Chlorides 115 130 115 118 116 118 108 108 110 115 110 " 115 Suspended Solids 1.0 2.0 1.5 10 5.5 6.0 12 6.5 2.5 13 3.0 2.0 Total Solids 312 300 274 414 420 346 100 300 314 246 224 250 Total Kjeldahl-N 0.55 0.51 0.82 1.6 0.96 3.0 0.99 1.0 2.8 1.1 1.2 3.5 Ammonia-Nitrogen 0.02 0.06 0.76 0.02 0.44 2.2 0.00 0.16 2.8 0.01 0.01 3.5 Nitrate-Nitrogen 0.4 0.4 0.3 0.1 0.3 0.0 0.0 0.1 0.1 0.0 . — — Total Phosphorus 0.07 0.05 0.09 0.18 0.06 0.25 0,08 0.07 0.34 0.10 0.08 0.40 Total Iron 0.07 0.06 0.07 0.11 0.11 0.56 0.27 0.12 1.0 0.11 0.05 0.63 Total Manganese 0.02 0.02 0.41 0.05 0.22 1.1 0.08 0.08 1.1 0.04 0.09 1.0 TABLE 5 (CONTINUED)

7/21/80 7/28/80 8/4/80 0.5m 5m 10m 0.5m 5m 10m 0.5m 5m 7m 10m PARAMETER pH (Standard Units) 9.1 7.5 7.0 7.7 7.2 7.0 8.4 6.9 6.8 7.1 Total Alkalinity 32 33 60 31 36 56 30 36 41 65 Total Hardness 65 65 69 66 69 71 63 69 70 72 Conductivity (nmhos/cm) 475 470 530 470 470 510 440 470 480 520 Chlorides 110 110 120 115 115 120 110 115 120 120 Suspended Solids 6.5 8.0 4.0 6.0 3.5 3.0 4.5 2.0 2.5 1.0 Total Solids 338 352 340 346 346 284 214 282 272 270 Total Kjeldahl-N 0.85 1.06 4.8 0.60 0.80 2.9 0.63 0.80 1.5 3.9 Ammonia-Nitrogen 0.01 0.08 4.3 0.01 0.36 2.7 0.03 0.38 1.1 3.8 Nitrate-Nitrogen 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.1 0.1 0.0 Total Phosphorus 0.08 0.08 0.40 0.09 0.07 0.29 0.09 0.07 0.12 0.49 Total Iron 0.13 0.13 1.1 0.17 0.17 0.63 0.10 0.16 0.27 1.0 Total Manganese 0.02 0.05 1.2 0.04 0.17 0.82 0.04 0.27 0.55 1.1 TABLE 5 (CONTINUED)

8/11/80 8/18/80 8/25/80 0.5m 5m 8m 10m 0.5m 5m 7m 10m 0.5m 6m 8m 10m PARAMETER pH (Standard Units ) 7.3 7.1 6.9 7.0 7.6 7.3 7.2 7.0 7.2 7.3 6.8 7.1 Total Alkalinity 29 32 33 30 30 34 30 31 25 31 48 55 Total Hardness 66 67 71 73 61 70 71 71 67 68 76 76 Conductivity (pmhos/cm) 450 460 500 520 440 470 490 520 460 480 520 540 Chlorides 110 110 115 110 104 90 110 125 100 100 105 110 Suspended Solids 11 3.5 5.5 1.5 3.0 2.0 2.5 3.0 3.5 4.0 5.0 3.0 Total Solids 330 200 290 290 318 300 286 296 346 336 340 336 Total Kjeldahl-N 0.48 0.76 2.0 4.1 0.63 0.90 2.1 4.4 0.85 1.4 3.6 5.6 Ammonia-Nitrogen 0.03 0.20 1.4 3.2 0.00 0.29 1.2 4.3 0.01 0.50 3.1 5.0 Nitrate-Nitrogen 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Total Phosphorus 0.07 0.07 0.18 0.40 0.06 0.07 0.17 0.57 0.05 0.05 0.30 0.58 Total Iron 0.14 0.08 0.42 0.87 0.04 0.00 0.07 1.1 0.05 0.10 0.70 1.4 Total Manganese 0.04 0.24 0.63 1.1 0.04 0.10 0.35 1.1 0.05 0.28 1.0 1.2 TABLE 5 (CONTINUED)

9/22/80 10/23/80 10/29/80 0.05m 6m 7m 8m 10m 0.5m 4m 6m 10m 0.5m 4m 6m 10m PARAMETER

pH (Standard Units) 7.6 6.9 6.7 6.7 6.6 7.2 7.2 7.2 7.8 7.1 7.0 7.0 7.4 Total Alkalinity 35 39 54 53 67 38 38 37 67 38 37 38 38 Total Hardness 70 73 67 73 73 72 72 69 78 71 69 69 69 Conductivity (urahos/cm) 450 470 500 500 520 440 440 440 500 430 430 430 430 Chlorides 105 105 115 115 120 90 90 100 100 95 100 100 95 -P- Suspended Solids 5.0 4.5 5.5 6.0 5.5 5.5 4.5 5.5 6.0 3.0 3.5 3.0 3.5 Ln Total Solids 320 294 318 314 308 290 276 278 292 290 288 290 288 Total Kjeldahl-N 0.99 1.3 2.6 2.6 4.4 1.4 1.3 1.3 5.5 1.5 1.7 1.9 1.6 Ammonia-Nitrogen 0.01 0.49 2.5 2.3 4.2 0.29 0.28 0.31 4.6 0.49 0.52 0.50 0.52 Nitrate-Nitrogen 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.1 0.2 0.1 0.1 Total Phosphorus 0.05 0.05 0.24 0.24 0.46 0.08 0.07 0.08 0.75 0.11 0.11 0.10 0.10 Total Iron 0.10 0.07 0.77 0.60 1.1 0.02 0.04 0.05 0.68 -0.08 0.05 0.07 0.06 Total Manganese 0.20 0.20 1.0 1.0 1.0 0.03 0.00 0.05 0.82 0.09 0.05 0.05 0.04 TABLE 5 (CONTINUED)

11/13/80 1/13/81 2/25/81 3/19/81 0.5m 5m 10m 0. 5m 5m 10m 0.5m 5m 10m 0.5ra 5m 10m rrtKJ\nc.iC,K pH Standard Units ) 7.9 7.7 7.7 7.3 7.2 7.0 7.1 7.2 6.9 7.3 7,1 6.9 Total Alkalinity 41 40 40 43 41 46 32 34 43 31 34 33 Total Hardness 66 66 66 89 86 86 44 44 51 64 64 61 Conductivity (tamhos/cm) 420 420 430 475 460 460 420 420 560 470 480 470 Chlorides 95 100 95 120 110 120 100 95 115 115 115 115 Suspended Solids 6.0 6.0 5.0 4.0 2.0 3.0 1.0 5.0 4.0 — — — Total Solids 240 274 236 — — 308 298 316 342 338 328 — Total Kjeldahl-N 1.5 2.0 2.0 0.83 0.80 0.99 0.85 0.88 1.2 0.66 0.75 0.64 Ammonia-Nitrogen 0.48 0.62 0.54 0.43 0.44 0.55 0.26 0.24 1.2 0.17 0.18 0.15 Nitrate-Nitrogen 0.1 0.1 0.1 0.2 0,2 0.3 0.3 0.3 0.3 0.4 0.4 0.4 Total Phosphorus 0.23 0.21 0.32 0.07 0.06 0.10 0.06 0.05 0.11 0.07 0.07 0.07 Total Iron 0.03 0.05 0.06 0.03 0.02 0.02 0.09 0.07 0.19 — — — Total Manganese 0.03 0.06 0.04 — 0.00 0.00 0.00 0.03 0.02 0.04 — — TABLE 6 SPY POND RESULTS OF CHEMICAL ANALYSES (mg/1) STATION 2

3/20/80 3/24/80 4/1/80 4/9/80 5/12/80 5/27/80 7/1/80 0.5m 5m 3m 0.5m 2m 0.5m 3m 0.5m 6m 0.5m 4m 6m PARAMETER pH (Standard Units) 7.5 7.5 7.4 7.8 7.7 7.8 7.6 7.7 9.1 7.1 7.5 7.8 Total Alkalinity 35 34 33 — 30 32 31 47 31 31 3.7 50 Total Hardness 62 62 62 — 65 67 67 69 69 64 66 67 Conductivity (ymhos/cm) 470 480 480 — 500 460 460 440 450 440 450 480 Chlorides 121 121 116 120 118 105 100 115 110 112 114 110 Suspended Solids 5.5 5.5 3.0 3.5 0.0 0.0 4.0 12 11 10 7.5 — Total Solids 300 306 318 346 276 348 320 36 422 312 454 — Total Kjeldahl-N 0.60 0.68 1.4 1.3 1.1 0.70 0.72 0.48 0.88 0.95 1.3 1.6 Ammonia-Nitrogen 0.32 0.32 0.35 0.16 0.14 0.04 0.06 0.01 0.82 0.02 0.30 1.1 Nitrate-Nitrogen 0.4 0.4 0.5 0.5 ' 0.5 0.5 0.5 0.3 0.0 0.1 0.1 0.0 Total Phosphorus 0.03 0.03 0.08 0.04 0.04 0.06 0.07 0.05 0.10 0.13 0.18 0.20 Total Iron 0.04 0.07 0.06 — 0.00 0.05 0.10 0.9 0.45 0.16 0.20 0.70 Total Manganese 0.02 0.02 0.02 — 0.02 0.03 0.03 0.04 0.92 0.06 0.16 0.90 TABLE 6 (CONTINUED)

7/7/80 7/14/80 7/21/80 7/28/80 8/4/80 0. 5m 4m 6m 0, 5m 4m 6m 0. 5m 4m 6m 0. 5m 4m 6m 0. 5m 4m 6m PARAMETER pH (Standard Units) 9.0 7.5 7.3 9.3 7.3 7.4 8.8 6.9 6.9 7.5 7.0 7.1 7.9 7.1 6.8 Total Alkalinity 33 35 57 31 33 54 40 34 65 34 40 52 31 33 57 Total Hardness 56 64 67 64 64 67 62 32 28 64 71 69 63 63 71 Conductivity (pmhos/cro) 470 480 518 470 460 500 480 480 520 480 480 490 440 430 500 Chlorides 104 106 110 115 105 115 115 120 120 120 120 110 105 110 115 Suspended Solids 12 7.0 6.5 12 11 6.5 8.0 11 8.0 5.5 4.5 5.5 6.5 5.0 5.0 Total Solids 348 292 .306 232 270 254 336 346 360 226 210 238 238 236 258 Total Kjeldahl-N A 1.2 2.7 1.0 1.1 1.9 1.00 1.31 4.0 0.79 1.1 1.7 0.58 0.78 2.6 Ammonia-Ni trogen 0.01 0.34 2.5 0.00 0.15 1.7 0.02 0.20 3.4 0.01 0.66 1.5 0.5 0.25 0.24 Nitrate-Nitrogen 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 2.9 0.0 0.0 0.0 0.0 0.0 0.0 Total Phosphorus * 0.11 0.32 0.08 0.12 0.24 0.08 0.09 0.41 0.08 0.14 0.27 0.08 0.10 0.35 Total Iron 0.26 0.76 2.0 0.10 0.11 0.46 0.14 0.17 2.4 0.17 0.27 1.7 0.15 0.12 1.6 Total Manganese 0.07 0.32 1.2 0.03 0.06 0.75 0.05 0.20 1.4 0.06 0.63 0.86' 0.06 0.29 1.1

Lab accident, no data TABLE 6 (CONTINUED)

8/11/80 8/18/80 8/25/80 9/22/80 0.5m 4m 6m 0.5m 4m 6m 0.5m 5m 6m 0.5m 4m 6m TrAKAMCilE-> A V MulfTITDK pH (Standard Units) 7.1 7.1 7.4 7.5 7.4 7.5 7.0 7.2 6.9 7.5 7.4 6.6 Total Alkalinity 28 33 59 ' 32 34 35 32 50 31 34 36 55 Total Hardness 64 66 76 63 64 72 67 67 68 70 62 73 Conductivity (ymhos/cm) 450 450 520 430 430 500 450 450 470 . 450 450 480 Chlorides 100 105 110 100 100 115 100 100 95 110 105 105 Suspended Solids 8.0 4.5 10.5 1.5 2.5 10.0 4.0 5.5 7.0 6.0. 5.0 15 Total Solids 250 310 312 256 262 296 348 332 342 300 324 352 Total Kjeldahl-N 0.60 1.1 4.7 0.77 0.81 3.9 1.0 1.4 2.7 0.88 1.0 2.6 Ammonia-Nitrogen 0.02 0.47 4.5 0.00 0.14 3.8 0.01 0.45 1.3 0.00 0.06 2.4 Nitrate-Nitrogen 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Total Phosphorus 0.07 0.08 0.64 0.07 0.06 0.60 0.-08 0.13 0.35 0.05 0.08 0.31 Total Iron 0.08 0.15 2.6 0.05 0.06 2.1 0.10 0.35 1.1 0.06 0.08 1.0 Total Manganese 0.05 0.38 1.5 0.07 0.06 1.4 0.05 0.39 0.73 0.01 0.02 1.0 TABLE 6 (CONTINUED)

-10/23/80 10/29/80 11/13/80 2/25/81 3/19/81 0.5m 3m 5m 0.5m 6m 0.5m 6m 0.5m 6m 0.5m 6m PARAMETER pH (Standard Units) 7.6 7.4 7.6 7.4 7.3 7.3 7.6 7.4 7.2 7.1 7.1 Total Alkalinity 36 35 35 36 36 38 40 28 33 33 32 Total Hardness 72 74 72 66 66 56 66 42 49 61 64 Conductivity (umhos/cm) 440 440 440 430 420 420 420 420 700 480 490 Chlorides 100 90 100 95 95 100 95 105 185 115 115 Suspended Solids 6.5 6.5 7.0 2.0 4.5 5.0 4.0 5.0 5.0 3.0 2.0 Total Solids 282 282 272 280 294 278 280 300 370 376 378 Total Kjeldahl-N 1.2 1.2 1.2 1.5 i.6 2.0 2.2 0.80 1.1 0.79 0.63 Ammonia-Nitrogen 0.15 0.13 0.14 0.37 0.37 0.47 0.48 0.11 0.48 0.17 0.29 Nitrate-Nitrogen 0.0 0.0 0.0 0.1 0.1 0.2 0.2 0.3 0.3 0.4 0.5 Total Phosphorus 0.08 0,08 0.08 0.19 0.08 0.17 0.51 0.07 0.10 0.08 0.07 Total Iron 0.07 0.05 0.03 0.11 0.07 0.10 0.06 0.04 0.09 0.03 0.09 Total Manganese 0.03 0.01 0.02 0.06 0.05 0.03 0.03 0.02 0.12 0.03 0.03 derived from nitrous and sulfurous gases originating from industrial sources. Lakes and watersheds with low carbonate or bicarbonate content are more susceptible to the pH lowering effect of acid rain than those with greater buffering capacity. The United States Environmental Protection Agency (1976) has set the criterion for alkalinity as "20 mg/1 or more as CaCO for freshwater aquatic life except where natural concentrations are less."

Total alkalinity values recorded at Stations 1 and 2 at Spy Pond during the study are presented in Tables 5 and 6. Values ranged .from a high of 47 mg/1 at Station 2 to a low of 25 mg/1 observed at Station 1. The average total alkalinity at both stations during the study was 34 mg/1. These data indicate that the buffering capacity of Spy Pond water is moderate and in no immediate danger of detrimental effects of acid rain. There is some question, however, as to the susceptibility of urban versus non-urban lakes to acid rain. Compared to rural watersheds, a high percentage of land exists under pavement in urban areas which prevents the rainwater from coming into contact with the soil where it may be buffered before reaching the lake.

The total hardness of a body of water refers to the total amount of alkaline earths present, which includes magnesium and calcium. As pointed out by Hutchinson (1957) two categories of hardness are normally distinguished: temporary, due to bicarbonate and carbonate; and permanent, due to sulfate and chloride. If a lake or pond has mostly "temporary" hardness, which can be removed by boiling and precipitating calcium carbonate, the hardness will be nearly equivalent to the bicarbonate alkalinity. In Spy Pond the average total hardness of the surface water at Stations 1 and 2 was 66 mg/1 and 63 mg/1, respectively; about double the total'alkalinity. This would indicate a high proportion of magnesium and calcium sulfates and chlorides, which is not unusual for an urban lake. The total hardness of Spy Pond can be described as "soft" (<75 mg/1) according to a commonly used classification scheme (Sawyer, 1960), but it appears relatively high in comparison to other Massa- chusetts lakes. For example, lakes and their watersheds situated in the limestone belt of western Massachusetts (i.e., the Berkshires) have average hardness values of between 70-90 mg/1 (Chesebrough et al, 1976; Chesebrough and Screpetis, 1978). On the other hand, lakes in north central Massachu- setts with bedrock of igneous origin have values of 10-15 mg/1 (Chesebrough and Screpetis, 1978) and in southeastern Massachusetts hardness often ranges from 20-30 mg/1.

Both alkalinity and hardness appear to have the property of reducing heavy metal toxicity in aquatic systems (EPA, 1976). Thus, aquatic life in a very weakly buffered lake (low total alkalinity) with very soft water (low total hardness) would be more susceptible to heavy metal toxicity than one with high alkalinity and hardness.

Spec i f i c Conductanc e ,^T o t al Solids and Chlorides_

The conductivity of natural waters is a measure of the ability of the water to conduct a current. This property is attributable to the ions in the water and it follows that the conductivity increases as the ion concentra-

51 tion increases. It is also true that the specific conductance increases as the ionic strength increases (Snoeyink and Jenkins, 1980). It has also been found that an empirical relationship exists between the ionic strength and total dissolved solids (TDS). Langelier (1936) described this as follows:

y = 2.5 x 10~5 x TDS rag/1

where y = ionic strength

There is, therefore, a direct relationship between the dissolved solids and conductivity of natural waters. In Spy Pond the data showed high values for conductivity and total solids (which in this case was mostly dissolved solids) The average epilimnetic conductivity, chlorides concentration, and total solids was 456 ymhos/cm, 110 rag/1, and 303 mg/1 respectively. The following table compares these values to those of Lake Mattawa in the north-central portion of the state (igneous bedrock), Pontoosuc Lake in the Berkshires (limestone belt), and Oldham Pond in southeastern Massachusetts (glacial moraine and igneous bedrock):

TABLE 7

CONDUCTIVITY • CHLORIDES TOTAL SOLIDS LAKE AND LOCATION (ymhos/cm) (mg/1) (rag/1)

Spy Pond, Arlington* 456 110 303 Lake Mattawa, Orange* 59 8 27 ' Pontoosuc Lake, Pittsfield 180 7 146 and Lanesborough* Oldham Pond, Pembroke and 180 45 118 Hanson**

A Average of one year's data ** Single survey July 16, 1980

Spy Pond values appear extremely high in comparison. The chloride level is especially high and doubtless the major cause of the high conductivity. The chloride level in lakes generally increases with proximity to oceans. For this reason Oldham Pond was used for comparison due to its proximity to the coast(16 km)as compared to Spy Pond(17.7 km). The high chloride concentration in Spy Pond is not the result of the nearness of the ocean. Rather, the lake appareritly acts as a sink for the dissolved solids from the urban watershed. A major portion of the roads in the drainage area are treated with roadsalt in the winter which eventually is washed into Spy Pond. As the discussion on tributary flow will show, even the small base flow from the Route 2 inlet showed consistently high levels of chlorides, total solids and specific conductance.

52 Iron and Manganese

Iron and manganese are essential micronutrients of microflora, plants, and animals and are toxic at high concentrations (Wetzel, 1975). Their importance in most freshwater bodies is not as great as that of phosphorus, or possibly nitrogen, because concentrations of these micronutrients generally exceed the demands by primary producers. Algae use iron in the synthesis of chlorophyll and proteins, while manganese is an essential component of nitrogen fixation (used by bacteria and blue-green algae) and in photosynthesis .

The situation is complicated by the relative abundance of various substances. For example, the hardness levels of lake water has been found to play a major role in the availability of iron (Wetzel, 1975). High levels of manganese, have been found to be inhibitory to both blue-green and green algal growth (Gerloff and Skoog, 1957) and to favor diatom growth (Patrick, et al. 1969).

The concentrations of iron and manganese in the epilimnion and hypolimnion of Spy Pond at Station 1 are illustrated in Figures 11 and 12. Both substances 'accumulated and reached high concentrations (>1.0 mg/1) in the hypolimnion during the summer, with manganese accumulating here noticeably earlier than iron- Manganese was released from the sediments before iron because reduction to the soluble manganous form takes place at a higher redox potential than that necessary for the reduction of iron to the ferrous form.

Hydrogen sulfide (H-S) (detected by the odor of sulfur) was also present in the anaerobic hypolimnion beginning on July 1 and ending on October 23 with the onset of fall overturn. The formation of ferrous sulfide, which is very insoluble, occurred in the hypolimnion of Spy Pond. It may have been for this reason that the iron content of the bottom waters did not reach even higher concentrations. The same process does not affect the manganese concentration because manganous sulfide is much more soluble. The epilimnion became relatively rich in iron but not manganese during the summer. The reason for this is unclear, but the iron was' probably constituted chiefly of organically complexed ferric hydroxide (FE (OH).,) or in particulate form associated with the seston.

Nitrogen and Phospjiorus

The principal nutrients involved in the process of eutrophication are nitrogen and phosphorus. Nitrogen is found in freshwater systems as a dissolved gas, as inorganic nitrogen (i.e. ammonia, nitrite, and nitrate), or as organically bound nitrogen (e.g. amino acids and proteins). Nitrate and ammonia ions are the most important forms as nutrients for phytoplanton and aquatic macrophytes. Pho'sphorus occurs in lake water as inorganic ortho- phosphate, dissolved organic phospate, organic and inorganically bound particulate phosphorus, and ionically bound phosphate. In Spy Pond cultural influence has greatly accelerated the normally slow eutrophication process by increasing the input of these nutrients and thus enhancing productivity.

Ammonia-nitrogen, nitrate-nitrogen, total Kjeldahl-nitrogen and total phosphorus data are presented together with the chemical data in Tables 5 and 6

53 1.2-•

FIGURE 11

TOTAL IRON AT STATION 1

a tr t- o

;;— EPIIIMNETIC IRON

Apr. May June July Aug. Sept. Oct. Nov. Dec. Feb. Mar. f 1.2 n-

FIGURE 12 1.0- TOTAL MANGANESE AT STATION 1

0.8- •

en E

3 0.6

0.4-•

0.2-- HYPOLIMNETIC MANGANESE EPIUMNETIC MANGANESE

20 Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Apr. 1980 1081 for Stations 1 and 2, respectively. Nitrogen and phosphorus levels were high at Spy Pond. The most often quoted threshold values leading to eutrophication are 0.015 rag/1 for total phosphorus and 0.33 mg/1 for nitrate plus ammonia-nitrogen (Sawyer and McCarty, 1967). The total phosphorus values nearly always exceeded this concentration and nitrogen values were often higher than 0.33 mg/1.

Figures 13 and 14 illustrate the flux of nutrient concentrations in the epilimnion and hypolimnion, respectively. Cycling of these nutrients is evident from these graphs and is directly related to the seasonal chemical and biological processes occurring in the lake. The following description summarizes the annual cycle of nitrogen and phosphorus concentrations in Spy Pond:

Spring 1980: The lake was undergoing complete circulation without thermal or chemical stratification; nitrogen values were quite high (0.4 mg/1 for nitrate and 0.36 mg/1 for ammonia-nitrogen) and the phosphorus level was also high (0.03-0.04 mg/1).

Summer 1980: Stratification began early (April) with hypolimnetic anoxia developing by June. Ammonia-nitrogen and phosphorus accumulated in the bottom waters while nitrate-nitrogen was un- detectable. In the epilimnion nitrate and ammonia-nitrogen were severely depleted by biological uptake when a large algal bloom peaked in early July. Total phosphorus in the epilimnion maintained a fairly constant concentration.* During August and September, however, phosphorus concentrations dropped slightly from 0.09 mg/1 to 0.05 mg/1. It is interesting to note that although there was apparently ample phosphorus available, nitrogen may have become limiting at this time because the algal population in the lake became relatively small. However, in late August the green algae were most abundant while the relative abundance of nitrogen fixing blue-green algae appeared to be declining. (This will be discussed in greater detail in the biological data section,)

Fall 1980: With the initiation of the fall turnover the lake underwent some rather drastic changes. As mentioned earlier the dissolved oxygen throughout the lake dropped noticeably. Figures 13 and 14 show how the store of bottom nutrients were dis- persed throughout the water column as the lake water mixed completely. The November 13, 1980 survey showed very high nutrient values throughout the lake under isothermic conditions (e.g., ammonia-nitrogen was 0.48-0.62 mg/1 and total phosphorus was 0.21-0.32 mg/1. An algal bloom occurred as a result of this sudden "fertilization" of the trophogenic layer. In turn, this algal bloom had the effect of lowering the epilimnetic concentrations' of total phosphorus and ammonia-nitrogen but not nitrate-nitrogen.

* The total phosphorus concentration for July 1 (0.18 mg/1) may be question- able; it,is inconsistent with the data trend. There were, however, heavy rains prior to this survey and certain other data were also high (e.g., suspended solids and total solids) indicating a possible impact from urban runoff. 56 f FIGURE 13 SURFACE CONCENTRATIONS OF AMMONIA NITROGEN,

NITRATE NITROGEN AND TOTAL PHOSPHORUS AT STATION 1

— NITRATE NITROGEN FIGURE 14 HYPOLIMNiON CONCENTRATIONS OF AMMONIA NITROGEN, NITRATE NITROGEN AND TOTAL PHOSPHORUS AT STATION 1

AMMONIA NITROGEN-:

01 oo

-TOTAL PHOSPHORUS

Mar. Apr. Feb. Mar. Apr. 1980 1981 Winter 1980- Under ice cover there was a moderate increase in hypolim- 1981: netic total phosphorus, nitrate-nitrogen and ammonia-nitrogen. In the epilimnion the ammonia-nitrogen and total phosphorus diminished from their peak values following the fall overturn. Nitrate-nitrogen, however, increased steadily in the epilimnion from November to March (see Figure 13). This suggests the possibility that the ammonia-nitrogen was being biologically converted to nitrate-nitrogen via nitrification. The nitrification reaction requires two moles of oxygen for every mole of ammonia-nitrogen converted:

NO, + H20 + 2H (Wetzel, 1975)

This process may have been partially responsible for the pro- nounced loss of dissolved oxygen following the fall turnover.

Spring 1981: Ice-out occurred unusually early in February and the lake water remained very cold (3-4 C) until mid-March. The February 25 survey was conducted shortly after ice-out and indicated that the lake had not yet undergone the complete circulation associated with the spring turnover. The March 19 survey, however, did take place with complete circulation underway. The data indicated that high nutrient concentrations existed throughout the lake. Total phosphorus measured 0.07 mg/1, ammonia-nitrogen 0.17 mg/1, and nitrate-nitrogen 0.4 mg/1. Such high values would generally forecast a rich algal growth for the lake.

Inlet and Outlet Data

A description of the inlet and outlet at Spy Pond can be found in the methods section. Chemical data collected from these stations are presented in Appendix B, Tables III and IV.

Most of the inlet showed considerable fluctuation. The pH was above 7.0 (Standard Units) on all occasions except four, when it was only slightly lower. The highest recorded pH occurred on July 1, 1980 when a pH of 8.8 was observed in the laboratory.

The total alkalinity, total hardness, conductivity, chlorides, and total solids all showed high values. The observed values for these parameters were generally higher than the average in-lake values.

The suspended solids, on the other hand, were generally very low. This agrees with the general appearance of the inlet water which was very clear.. The very high concentration observed on February 11, 1981 occurred during a rain storm.

The nutrient concentration of the inlet water generally showed high nitrate- nitrogen and total phosphorus and moderate ammonia-nitrogen. The nitrate-

59 nitrogen and ammonia-nitrogen concentrations were generally higher than the in-lake values while the total phosphorus values from the inlet were comparable to the lake concentrations.

The outlet values for pH, total alkalinity, total'hardness, conductivity, chlorides, suspended solids, and total solids were similar to in-lake concentrations. The nutrient content and seasonal trend of the outflow samples were also comparable to Stations 1 and 2.

HistoricalComparison

Valuable insight into the magnitude and rate of change in a lake's trophic status can be obtained from examining historical water quality data that exists for the lake. Such data are available from several reports on Spy Pond from 1953-1972. The data, listed in Table 8 show the chloride and nutrient levels have increased since 1953 while the total alkalinity and hardness has not changed significantly. This comparison indicates that those parameters most susceptible to change due to cultural eutrophication have increased. Most probably the chloride concentrations have increased from road salt, and nutrients have increased due to urban runoff.

Biological Results

Bacteriological Data

The main purpose for testing lake water for coliform or streptococci bacteria is to identify and locate possible sewage contamination. The rationale for using these tests are several, as explained by the U.S. Environmental Protec- tion Agency (1976):

"Microbiological indicators have been used to determine or indicate the safety of water for drinking, swimming, and shellfish harvesting. As our knowledge concerning microbiology has increased, so has our understanding of the complex interrelationship of the various organisms with disease. Viruses causing a number of diseases and non-fecally associated bacteria causing infections of the ears, eyes, nose, and throat all have been isolated from water. The relationship between numbers of specific disease-causing organisms in water and the potential for transmission of disease remains elusive since the number of organisms required to cause disease varies, depending upon the organism, the host, and the manner in which the bacteria and host interact. For example, in some instance a single cell>of Salmonella sp., or a single plaque-forming unit (PFU, a standard means for measuring virus concentrations in tissue culture) may be all that is necessary to cause a disease; however, in other instances the numbers of bacteria necessary to cause an illness may be up to millions or billions or even more viable organisms. The use to which water is put, the type of water, and the geographical location are all factors to be weighed in determining safe microbiological criteria!1

60 TABLE 8 SPY POND COMPARISON OF HISTORICAL DATA (rag/1)

COMMONWEALTH OF MASSACHUSETTS (1953) HABITAT (1972) CORTELL (1972) PARAMETER RANGE AVERAGE RANGE 8/23/72 Free Ammonia-Nitrogen 0.010 - 0.210 0.068 Total Albumlnoil Ammonia-Nitrogen 0.180 - 0.650 0.440 — Ammonia-Nitrogen 0.30 Nitrite-Nitrogen 0.00 - 0.015 0.004 — Nitrate-Nitrogen 0.100 - 2 06 0.236 0 — Total Phosphorus 0.00 - 0.015 0.003 0.02 - 1.8 0.016 - Chlorides 25 - 27 26.4 125 - 550 192 Hardness 58 - 74 70 — . — Alkalinity 36 - 41 38 50 Iron 0.11 Manganese 0.26 —

Commonwealth of Massachusetts, Special Report of the Metropolitan District Commission of the Sanitary Condition of Spy Pond in the town of Arlington, House Document Number 2208, 1953, Under Chapter 86 of the Resolves of 1951.

"Burnett, Christopher D. Proposal to Study the Eutrophication Problem of Spy Pond, Habitat, Inc., Belmont, Massachusetts, 1972.

Cortell, Jason M. and Associates. Report of Conditions in Spy Pond, Arlington, Massachusetts; A Historical Synopsis, Wellesley Hills, Mass., 1973. The total coliform group includes soil bacteria while the fecal coliform bacteria are found in the intestinal tract of animals. The ratios of fecal coliform to total coliform (FC/TC) and fecal coliform to fecal streptococci (FC/FS) are often used to evaluate the source of contamination (Olivieri, 1980). Sewage contamination is indicated by a FC/FS ratio greater than 0.1. An FC/FS ratio greater than 4.0 indicates human fecal pollution and a ratio of less than 1 suggests the source of fecal contamination is from animals. Those ratios between 1,0 and 4.0 are considered not conclusive.

The indicator ratios should be used with caution since the method is not without its limitations. As pointed out by Olivieri (1980):

"Too many factors will influence the densities of fecal coliform and fecal streptococci. The magnitude of these densities along with the volume of water which carries the contamination, combined with the numerous environmental factors that will affect the levels of these microorganisms, make the useful application of the FC/FS ratio difficult in the urban environment "

Therefore, these rations are not intended to be used as the only method of evaluating the source of contamination in a complex system.

The Massachusetts Division of Water Pollution Control (1978) has set the criteria for occurrance of fecal coliform bacteria in waters used for primary and secondary contact recreation at a log mean of 200/100 ml for a set of samples.

The bacteriological data for Stations 1 and -2 and the inlet and outlet are presented in Table 9. Bacterial levels in the open water stations were generally low and never exceeded the State's level. Slightly elevated counts of bacteria were observed at Stations 1 and 2 on July 1, August 4, 11, September 22 and October 29, 1980. In all of these cases except on Septem- ber 22, a heavy rainstorm had occurred within a day of sampling. Rain occurred four days prior to the September 22 survey. This suggests that the stormwater discharging into the lake affected the bacteriological levels in the open water stations. These effects are due to the natural die-off rate of the bacteria involved.

In the inlet samples the total coliform count reached a high of 30,000 cells/ 100 ml after a heavy rain in August. Ranges for fecal coliform and fecal streptococcus were <5-7,000 cells/100 ml and <5-13,000 cells/100 ml respectively. Fecal coliform counts from inlet samples often exceeded the maximum levels set by this agency.

Thirty-nine percent of the inlet samples had FC/TC ratios indicating sewage contamination (FC/TC >0.1). Of these, the majority were due to human fecal pollution. It should be noted that in some cases the number of organisms in a particular sample were too low to statistically apply this indicator ratio. The bacteriological quality of the outlet water was similar to Stations 1 and 2.

62 TABLE 9 SPY POND RESULTS OF BACTERIOLOGICAL TESTING (cells per 100 ml)

DATE TEST STATION 1 STATION 2 INLET OUTLET __ __ 3/12/80 Total coliform 1,000 30 Fecal Coliform 55 <5 Fecal Strep* — — <5 <5 — — 3/20/80 Total Coliform 50 90 6,000 60 Fecal Coliform <5 <5 450 <6 Fecal Strep. <5 <5 200 <5

3/24/80 Total Coliform 10 110 5,400 10 Fecal Coliform <5 <5 800 <5 Fecal Strep. <5 25 200 <5

4/1/80 Total Coliform 50 40 9,000 10 Fecal Coliform ' <5 <5 1,600 <5 Fecal Strep.

4/9/80 Total Coliform 10 40 24,000 10 Fecal Coliform <5 <5 2,000 <5 Fecal Strep. 130 150 <5 ___ _—_ 4/14/80 Total Coliform 4,200 30 Fecal Coliform — 600 <10 Fecal Strep. —

4/22/80 Total Coliform 2,400 40 Fecal Coliform 70 <10 Fecal Strep. — — 10 <10 _—_ — Total Coliform 4,800 100 4/28/80 — Fecal Coliform 1,100 <10 — Fecal Strep. — 180 <5 —__ — Total Coliform 15,000 60 5/8/80 — Fecal Coliform 7,000 <5 — Fecal Strep. — 800 <5 — — 5/12/80 Total Coliform 100 240 10,000 220 Fecal Coliform <5 10 600 10 Fecal Strep. _. 5/19/80 Total Coliform 5,000 80 Fecal Coliform 250 10 — — Fecal Strep. <5 <5 — —

63 TABLE 9 (CONTINUED)

DATE TEST STATION 1 STATION 2 INLET OUTLET

5/27/80 Total Coliform 10 10 1,200 30 Fecal Colifonn <5 - <5 60 <5 Fecal Strep • <5 <5 <5 <5

6/3/80 Total Coliform 24,000 <36 Fecal Coliform — — 4,300 <36 Fecal Strep . — — 300 10 — 7/1/80 Total Coliform 100 500 15,000 120 Fecal Coliform 20 60 400 20 Fecal Strep. 10 <5 <5 <5

7/7/80 Total Coliforra 5 5 5,000 5 Fecal Coliform <5 <5 450 <5 Fecal Strep.

7/14/80 Total Coliform 5 5 900 10 Fecal Coliform <5 <5 100 <5 Fecal Strep . <5 <5 <5 <5

7/21/80 Total Coliform 30 20 7,000 20 Fecal Coliform <5 <5 600 <5 Fecal Strep . <5 <5 <5 <5

7/28/80 Total Coliform Bacterial results for 7/28/80 not Fecal Coliform reliable due to two days lapse Fecal Strep. between collection and analysis.

8/4/80 Total Coliform 10 300 15,000 160 Fecal Coliform <5 60 1,200 10 Fecal Strep . <5 <5 40 <5

8/11/80 . Total Coliform 150 100 30,000 100 Fecal Coliform 60 10 4,600 5 Fecal Strep. <5 <5 200 <5 •

8/18/80 Total Coliform 140 20 9,000 30 Fecal Coliform <5 <5 1,000 <5 Fecal Strep . <5 <5 10 5

8/25/80 Total Coliform 20 100 1,800 10 Fecal Coliform <5 <5 150 . 10 Fecal Strep . <5 <5 50 <5

64 TABLE 9 (CONTINUED)

DATE TEST STATION 1 STATION 2 INLET OUTLET

9/22/80 Total Coliform 10 120 6,000 160 Fecal Coliform 10 40 400 10 Fecal Strep. <5 10 60 .20

10/23/80 Total Coliform 100 20 5,100 300 Fecal Coliform <5 <5 80 20 Fecal Strep. <5 <5 300 <5

10/29/80 Total Coliform 100 300 30,000 500 Fecal Coliform 20 100 2,800 60 Fecal Strep. <5 40 260 20

11/13/80 Total Coliform 100 10 2,900 20 Fecal Coliform 10 . <5 400 <5 Fecal Strep. <5 <5 80 <5

1/13/81 Total Coliform 40 6,500 Fecal Coliform ~—~ 1,600 •~—— Fecal Strep. *™

2/11/81 Total Coliform -^-* 24,000 .. Fecal Coliform 430 Fecal Strep. . —— — 13,000 — — 2/18/81 Total Coliform <20 <20 Fecal Coliform — Fecal Strep. —

2/25/81 Total Coliform 60 160 2,000 120 Fecal Coliform 20 <10 100 60 Fecal Strep. 40 100 2,500 100

3/19/81 Total Coliform <5 10 <5 <5 Fecal Coliform <5 5 <5 <5 Fecal Strep.

65 The location of other stations sampled for bacteriological analysis have been previously described in the Methods section. These stations were established to monitor the sanitary condition of the water in areas likely to be frequented by the public or impacted by the storm drains. The results from these tests are presented in Table 10. The August 4 and October 29 surveys were preceded by rain and the August 25 and September 22 surveys were preceded by several days of dry weather.

The data indicate that coliform bacteria were present at nearly every station on each survey.

The samples collected from near the swimming areas (Stations A and E) always contained coliform bacteria. The highest fecal coliform count of 500 cells/ 100 ml was recorded from Station A on August 4, 1980. The data also indicate that the bacterial counts were generally higher for those surveys which were preceded (24 hours) by rain.

P hy to p1ankt on

The phytoplankton data and a list of the genera present at Stations 1 and 2 can be found in Appendix C, Tables I through IV. Figure 15 graphically represents the total counts of phytoplankton collected at the open water stations during the study. The relative abundance of the various groups of algae present in the lake throughout the year is illustrated in Figure 16.

According to the Massachusetts Lake Classification System and others (Weber, •1974) the total number of algae in Spy Pond places the lake in the eutrophic category. ' The high chlorophyll ji concentrations (see Figure 17) were also indicative of eutrophic conditions (Vollenweider and Kerekes, 1980).

Seasonal succession of the dominant algal species was typical of a temperate, eutrophic lake (Wetzel, 1975). In early April there was a diatom CBacillario- phyceae) bloom and high numbers of Mastigophora were found; in early to mid- July the green algae (Chlorophyceae) dominated; followed soon after by an increase in blue-green algae (Cyanophyceae); in November the lake experienced another increase in diatoms and Mastigophora. Some of the blue-green algae present (Anabaena sp. , Aphanizomenon sp., Mlcrocystis sp,) are often associated with nuisance conditions in eutrophic lakes.

Two major peaks in algal numbers and chlorophyll a. concentrations are evident from the data. In July, both indices coincided with a bloom of green algae. The second major peak of chlorophyll _a concentation occurred in late October during overturn but did not coincide with the peak in numbers of total algae that occurred in mid-November.

The reason for this discrepancy is unclear, but it is worth noting that the chlorophyll a levels for Stations land 2 were similar during every survey

66 TABLE 10 SPY POND SANITARY SURVEY DATA

RESULTS (organisms per 100 ml) Total Fecal Fecal STATION DATE Coliform Coliform Strep

A 8/4/80 800 500 20 A 8/25/80 40 30 <5 A 10/29/80 200 80 20 B 8/4/80 300 70 5 C 8/4/80 60 5 <5 C 9/22/80 260 30 40 D 9/22/80 150 10 20 E 8/4/80 100 20 <5 F 8/25/80 ~40 <5 <5 G 8/4/80 1,-500 80 20 H 9/22/80 740 480 120 I 10/29/80 400 160 200 J 8/25/80 160 10 <5 K 8/4/80 1,900 300 <5 K 9/22/80 540 80 40 L 8/4/80 900 80 <5 L 9/22/80 200 20 30 L 10/29/80 300 60 10 M 10/29/80 200 30 80 N 8/4/80 200 50 <5 N 8/25/80 140 40 <5

67 FIGURE 15

TOTAL LIVE PHYTOPLANKTON (cells/ml) 10 T AT STATIONS 1 and 2

— STATION 2

STATION 1—

at oa E 4 ^ 10-

10" I I •h 12 27 14 28 It 25 22 I 13 13 25 19 6 20 1 7 21 4 IB 29 25 Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Jan. Feb. Mar. Apr. 1980 1981 r FIGURE 16 SEASONAL VARIATIONS IN PHYTOPLANKTON AT STATION 1

CJ 5£ < a

e> to

25 19

Fell. Mur. A|ir. 1GU1 50-r

CHLOROPHYLL a DATA FIGURE 17

40" AT STATIONS 1 AND 2

E 30-•

X CL O CC 20-

10--

24 9 12 27 20 19 Mar. Apr. June Sept. 29 Dec. Fell. Mar. A|ir. May July Aug. Oct. Nov. 1980 19K1 except October 23. It is possible, therefore, that a sampling or laboratory error influenced these data.

The high algal mass present in Spy Pond affected various water quality parameters. During the spring the lake water was brown and turbid. Begin- ning in July the water appeared green and later returned to a brownish hue during September and October. These color trends correlated well with the pigmentation of the dominant algal genera present.

The algae also affected the pH values of the surface waters. When large populations of algae exist, the carbon dioxide utilization rate is higher during photosynthesis than the generation rate of carbon dioxide by respiration. This reduced the carbon dioxide concentration (not measured in this study) and increases pH. At Spy Pond the pH data reflected biogenic influence from the algal photosynthesis. Field tests for pH (using a Hach model 17N Wide Range pH kit) during the summer always showed higher values than the laboratory results. It is possible that transportation of the samples in a dark cooler affected the photosynthesis respiration balance and thereby affected the pH, as reported.

As previously reported, water transparency was also adversely affected by algal blooms (see Figure 9A). Figure 9 shows that the suspended solids were high at the same time a drop in transparency was observed in July. This peak occurred during an algal bloom but other increases in suspended solids did not correlate well with the other algal blooms. The stormwater influent, which is very high in suspended solids may have masked the algal impact on the suspended solids.

The oxygen profile was also greatly influenced by high algal density. The very productive photic zone resulted in an anoxic hypolimnion either directly, through decomposition of falling seston or indirectly by decomposition of organic sediments.

Spy Pond also experienced an abundance of filamentous algal growth along the shores and littoral zones of the lake. It was often associated with aquatic macrophyton, rocks, and other debris such as submerged tree branches. This algae frequently grew in large mats. Identification of the growth on different surveys showed the dominant forms to be Rhizoclonium sp. and Mcmgeotla sp.,with lesser amounts of Spirogyra sp., Hormidium sp., and Nostcic sp.

Macrophyton

Historically, aquatic macrophytes in Spy Pond have been a problem. Photo- graphs of Spy Pond taken during the time when ice harvesting was active (Balazs, 1973) show prolific-weed growth, especially in the vicinity of Elizabeth Island.

The most common aquatic plant identified in the lake during July and August, 1980 was Potamogeton pectinatus Linnaeus, or sago pondweed (see Figure 18) This plant, which prefers hard or brackish water (Fassett, 1972) was especially prevalent around Elizabeth Island and along the southeastern and

71 mile 1/4

kilometer 1/4

LOCATION

Potamogeton pectinatus (Sago Pondweed) Lysimachia ciliata (Loosestrife) Phragmites sp. (Reed Grass) Decadon verlicillatus (Swamp Loosestrife) Potamcgelon crispus {Curty Pondweed)

Juncus sp. (Rush) Sparganium sp. (Bur Reed) LEGEND Nitella (Stonewort) * Typha tatifolia (Common Cattail) Listed in order of abundance Lemna sp. (Duckweed) Sagittaria sp. (Arrowhead)

* technically, a macroscopic algae IH^M^B^MT DEOE • DWPC- Technical Services Branch

DISTRIBUTION OF AQUATIC VEGETATION FIGURE 18 JULY - AUGUST 1980

72 southern shores. The sago pondweed was frequently observed associated with filamentous algae (mostly Rhizoclonium sp. and Mougeotia sp.). As the summer season progressed the pondweed deteriorated while the filamentous algae appeared to increase. The lake's perimeter also was well populated with Lysimachia ciliata Linnaeus (fringed loosestrife) which has a distinc- tive yellow corolla (flower).

Phragmites sp.* (reedgrass) was well established on the southwest side of Elizabeth Island, the southern shore near the recreation field off Spy Pond Parkway, and along the western shore near Gould Road.

The aquatic plant growth was somewhat denser in the southern bay due to shallower depths that provided a more extensive littoral zone.

The open water of Spy Pond was free of any rooted aquatic plant growth due to the water depth. Plant growth was confined to the peripheral littoral zones and the vicinity of the island. The eastern bay was remarkably free of macrophyton during this study. Repeated attempts of dragging a plant hook produced only dead leaves and miscellaneous debris. It is likely that the low water transparency in the lake acted as a limiting factor on the aquatic macrophyton growth. The transparency at Station 1 varied between 1.2 and 1.6 meters during most of the study. This is considered very low and could certainly limit rooted aquatic plant growth in the lake. If the water transparency is improved, macrophyte growth may be enhanced if nutrients remain available. This should be considered in any restoration program.

Storm Drain Data

The results from the periodic storm drain sampling are presented in Table 11. Figure 19 illustrates the storm drain system of the watershed. Descriptions of each drain pipe are listed in Table 12. For pipe locations and storm drain sampling station locations refer to Figure 3. The results of June 3, 1980 represent "first flush" data on drains 24, 25, 26, 26A, 29, 30, and 35. Data collected during a sampling intensive wet weather survey on July 23, 1980 are presented in Table 13. Rainfall recorded at Boston and Chestnut Hill for this date was less than 0.054 mm (0.05 inches) and did not provide a large runoff.

The data collected from Spy Pond indicated that most of the sediment and nutrient load occurred during the first flush and a short period thereafter. The April 1980 data, for example, showed relatively low values for those parameters tested. These drains were sampled a considerable time after the storm event and the pollution load had been effectively flushed out.

The data collected on June 3, 1980 and during the organized wet weather survey on July 23, 1980 gave a clear indication of the pollution load delivered to the lake during the initial discharge period. Both phosphorus and coliform bacteria levels were very high. The February 11, 1981 data, which was collected a short time after the first flush but with rain still falling, also showed very high nutrient levels and coliform numbers. Total manganese and

* This was very Likely Phragmiteg maximum (Forskal) Chivenda but was not technically keyed out.

73 TABLE 11 SPY POND

STORM DRAIN DATA (mfi/I) DATE 3/20/80 STORM DRAIN NUMBER

PARAMETER j/c/ BU 5/8/80 PH (Standard Units) 7.1 — ~^~——^JL_—~~~J±___ Total Alkalinity 7.3 10 7.0 Total Hardness 10 7.4 13 6'9 6.0 Conductivity 12 58 5.9 4.0 . (mnhos/cm} 82 4.0 86 9.0 Colorides 6.0 88 Suspended Solids 14 44 26 2.5 10 Total Solids 0.5 55 12 50 1.0 - 10 Total Kjeidahl-K 68 0.0 0.30 64 o.o 4_5 0.74 12 ^onla-Nltrogen 48 52 0.12 1.5 ^ft 0.12 1.4 JU 0.2 69 0.06 °' 0.67 Total Phosphorus 0.2 0.62 0.72 0.01 o.io Ot20 Total Iron 0.04 6.8 0.08 0.00 0.10 0.6 0>5 Total Manganese 0.00 0.04 0.3 0.00 0.00 0.08 0.15 Total Coliform* 0.02 0.26 0.02 0.11 fecal Coliform* 0.12 900 5 Strep* <5 600 <5 <2 13 ° 1,200 9,000 130 <1D 400 A, 000 <5 120 1,300 TABLE 11 (CONTINUED)

DATE 5/8/80 5/8/80 5/8/80 5/8/80 5/8/80 6/3/80 6/3/80 6/3/80 6/3/80 6/3/80 STORM DRAIN NUMBER 11 20 24 30 36A 24 25 26 26A 29

PARAMETER pH (Standard Units) 5.7 5.4 5.7 6.1 5.2 6.8 6.7 6.5 6.1 6.1 Total Alkalinity 4.0 2.0 3.0 4.0 3.0 16 15 14 11 32 Total Hardness 6.0 5.0 11 14 9 Conductivity 35 26 54 45 39 120 96 120 110 320 (pmhos/cm) Chlorides 1.0 7.0 4.0 1.0 0.0 12 3.0 1.0 1.0 8.0 Suspended Solids 9.0 12 11 20 26 — Total Solids 52 36 56 62 48 — Total Kjeldahl-N 0.89 0.81 0.98 0.96 1.0 5.6 3.6 1.9 1.5 22 Ammonia-Nitrogen 0.24 0.23 0.36 0.41 0.45 0.17 0.23 0.69 0.05 0.12 Nitrate-Nitrogen 0.4 0.3 0.8 0.9 0.7 0.0 1.1 0.1 0.2 0.0 Total Phosphorus 0.18 0.08 0.14 0.17 0.19 1.9 1.9 1.4 1.5 8.2 Total Iron 0.19 0.27 0.20 0.08 0.27 Total Manganese Total Coliform* 3,500 1,200 40,000 4,000 4,600 2.4X106 93,000 240,000 240,000 2.4X10'

Fecal Coliform* 600 10 6,000 160 760 93,000 43,000 43,000 43,000 240(00i Fecal Strep* 100 200 700 1,200 60 2,000 100 3,000 6,000 10,000

*Cells per 100/ml TABLE .11 (CONTINUED)

DATE 6/3/80 6/3/80 6/3/80 6/3/80 6/3/80 7/1/80 7/1/80 8/11/80 8/11/80 8/11/80 STORM DRAIN NUMBER 29** 30 33 34 35 23 23*** 4 5 6

PARAMETER pH (Standard Units) 5.1 6.1 6.7 6.3 6.5 6.5 Total Alkalinity 4 5 11 3 3 2 Total Hardness 20 10 13 13 15 16 Conductivity 78 105 78 50 58 56 (umhos/cm) — Chlorides 1.0 1.0 8 3 2 2 Suspended Solids 70 8.5 15 10 — Total Solids 136 38 46 52 Total Kjeldahl-N 4.0 4.6 1.0 0.98 1.0 1.0 Ammonia-Nitrogen 0.46 0.48 0.05 . 0.00 0.04 0.04 Nitrate-Nitrogen 1.5 2.0 0.3 0.6 0.6 0.8 — Total Phosphorus 0.87 2.0 0.44 0.23 0.27 0.29 Total Iron 2.1 2.6 0.47 0.40 Total Manganese 0.11 1.5 0.09 0.10 Total Coliform* 93,000 240,000 <36 9,300 240,000 46,000 4,3000 54,000 79,000 120,000 Fecal Coliform* 24,000 93,000 <36 4,3000 43,000 4,200 430 1,000 10,000 15,000 Fecal Strep* 3,000 2,000 <10 100 2,000 2,400 400 20 1,000 400

* Cells per 100/ml ** Bacteriological sample taken approximately ten minutes after the preceedlng #29 sample ***Collected from small pool In front of #23 storm drain which Is part of the lake TABLE 11 (CONTINUED)

DATE 2/11/81 2/11/81 2/11/81 2/11/81 2/11/81 2/11/81 2/11/81 2/25/81 2/25/81 STORM DRAIN NUMBER 4 5 6 10 11 11 36A 20 34 PARAMETER pH (Standard Units) 6.6 6.5 6.6 6.2 6.2 6.3 6.4 6.1 6.1 Total Alkalinity 11 13 15 8.0 5.0 10 15 3.0 3.0 Total Hardness 3 4 Conductivity 810 1,550 1,550 200 3,300 1,750 1,350 32 19 (pmhos/cm) Chlorides 230 460 480 48 106 530 410 5 5 Suspended Solids 43 71 68 18 279 74 113 34 53 Total Solids 552 1,004 1,016 172 2,294 1,162 838 186 72 Total Kjeldahl-N 2.3 3.4 4.6 3.5 2.8 2.7 2.5 0.67 1.0 Ammonia-Nitrogen 0.09 0.05 0.03 0.27 0.36 0.10 0.04 0.06 0.45 Nitrate-Nitrogen 0.9 0.9 0.9 0.8 0.8 1.1 0.5 0.1 0.1 Total Phosphorus 0.35 0.47. 0.50 0.65 0.42 0.35 0.47 0.10 0.20 Total Iron 0.14 0.08 Total Manganese 0.01 0.02 Total Coliform* 15,000 4,600 46,000 24,000 910 840,000 43,000 <20 170 Fecal Coliform* 430 2,400 24,000 2,300 360 3,900 4,600 . <10 100 Fecal Strep* 15,000 25,000 27,000 5,000 1,000 <1,000 32,000 500 1,200

*Cells per 100/ml milt

Watershed Boundary —

DEQE/DWPC Technical Strvlcit Branch

WATERSHED STORM DRAIN SYSTEM TABLE 12 SPY POND STORM DRAINS

NUMBER SIZE (cm) BRIEF DESCRIPTION

1 30.5 Concrete - drains access area 2 30.5 Concrete, corrugated; Crushed where emerges from shore 3 30.5 Concrete, corrugated 3a 30.5 Concrete drain 4 104 Concrete culvert 5 61 Iron, corrugated, rusted out bottom 6 39 Cast iron 7 - Open asphalt, direct from road, not a pipe 8 30.5 Concrete drain (half filled with dirt) 9 30.5 . Concrete 9a 20 Ceramic tile with broken end 10 ' 46 Concrete channel 11 46 Concrete 12 30.5 Corrugated metal, obliquely truncated, pitched 13 30.5 Corrugated metal, obliquely truncated, pitched 14 30.5 Corrugated metal, obliquely truncated, pitched 15 Iron, circular 16 30.5 Corrugated metal, obliquely truncated, pitched 17 30.5 Concrete 18 30.5 Corrugated metal, obliquely truncated, pitched 19 39 Concrete (in mud) 20 30.5 Corrugated metal, obliquely truncated, pitched 20a 21 38 Clay (hidden under tree stump) 22 30.5 Clay, in concrete headwork, at end of Gould St. 23 38 Glazed clay, recessed into bank, at end of Chapman St. 24 53 Concrete, large headwork of concrete, at end of Spring Valley Rd. 25 53 Concrete, large headwork of concrete, below Lakeview St 26 20 Glazed clay 26a 30.5 Iron, by phone pole at Hopkins Rd.

79 TABLE 12 (CONTINUED)

NUMBER SIZE (cm) BRIEF DESCRIPTION

27 10 Iron, totally filled with mud 28 41 Iron-lined concrete, below Addison St. 29 46 Glazed clay, in broken brickwork 30 46 Concrete, partially filled with mud, below Wellington St, 31 25 Concrete, partially filled 32 20 From under Boys' Club 33 20 From under Boys1 Club 34 46 Concrete 35 20 Asbestos cement 35a 13 Concrete drain 36 30.5 Concrete, in brickwork (1 of 2 pipes) at Pond Lane 36a 38 Concrete, in brickwork (1 of 2 pipes) 37 46 Corrugated concrete, drains from RR tracks

80 TABLE 13 SPY POND STORM DRAIN WET WEATHER SURVEY

STORM DRAIN NUMBER 23 DATE: JULY 23, 1980

TIME OF COLLECTION (hr) : 1050 1055 1100 1105 1120 1135 1150 1220 PARAMETER pH (Standard Units) 6.1 6.0 6.0 6.1 6.9 7.1 6.9 7.0 Total Alkalinity 20 15 9 7 57 45 37. 22 Total Hardness 130 79 62 23 98 93 94 66 Conductivity (umhos/on) 375 220 120 78 410 330 330 310 Chlorides 15 5 4 1 32 27 25 25

00 Suspended Solids 20 36 22 40 109 54 47 33 Total Solids 550 324 108 70 538 854 388 319 Total Kjeldahl-N 9.0 5.9 3.3 2.5 2.9 5.5 5.2 4.0 Ammonia-Nitrogen 3.5 2.8 1.7 1.3 2.3 2.1 1.5 1.7 Nitrate-Nitrogen 8.3 1.5 1.5 1.3 1.7 5.7 5.5 1.8 Total Phosphorus 1.5 1.5 0.88 1.0 1.4 0.96 0.80 0.68 Total Iron 0.69 0.52 0.14 0.12 1.1 0.'39 0.48 0.29 Total Manganese 0.45 0.61 0.21 0.16 1.0 0.25 0.36 0.06 Total Coliform* 90,000 40,000 70,000 62,000 93,000 93,000 Fecal Coliform* 20,000 9,000 - 12,000 18,000 93,000 43,000 Fecal Strep* 40,000 22,000 25,000 20,000 ** A* Aft A*

*Cells per 100 ml **Turbidity interference in fecal strep test» sample unable to be analyzed. TABLE 13 (CONTINUED)

STORM DRAIN NUMBER 24 DATE: JULY 23, 1980

TIME OF COLLECTION (hr) : 1105 1110 1115 1120 1135 1150 1205 PARAMETER pH (Standard Units) 6.7 7.4 6.4 5.0 4.2 4.2 .4.3 Total Alkalinity 25 56 55 13 12ft* 9** 7** Total Hardness 67 69 77 83 78 74 83 Conductivity (nmhos/cm) 330 390 420 390 370 360 350 Chlorides 56 59 54 40 37 32 29

00 Suspended Solids 139 127 108 110 71 51 37 10 Total Solids 364 370 336 552 710 754 716 Total Kjeldahl-N 7.7 7.0 8.7 8.5 8.5 7.8 7.2 Ammonia-Nitrogen 0.64 3.2 1.2 1.4 0.60 2.1 3.1 Ni t ra t e-Ni t rogen 8.6 1.5 0.9 0.7 0.5 0.5 0.5 Total Phosphorus 5.0 3.1 2.8 2.5 2.5 2.2 2.2 Total Iron 0.12 0.17 3.0 8.1 7.7 7.1 6.7 Total Manganese 0.00 0.00 0.20 0.47 0.38 0.37 0.39 Total Coliform* 150,000 930,000 240,000 430,000 2.4 X 106 24,000 43,000 6 Fecal Coliform* 9,300 43,000 15,000 24,000 2.4 X 10 4,300 4,300 Fecal Strep* *** -.— *** *** *** *** A** ***

*Cells per 100 ml **Acidity ***Turbidity interference in fecal strep test TABLE 13 (CONTINUED

STORM DRAIN NUMBER 36A DATE: JULY 23, 1980

TIME OF COLLECTION (hr) : 1055 1100 1105 1110 1120 1135 PARAMETER pll (Standard Units) 5.6 6.0 5.3 5.1 4.3 3,6 Total Alkalinity 4 6 5 5 Total Hardness 11 12 36 31 53 49 Conductivity (pmhos/cm) 76 82 138 170 260 385 Chlorides 9 9 9 10 12 14 00 Suspended Solids 2.0 4.0 26 CO 13 15 17 Total Solids 50 38 138 194 296 398 Total Kjeldahl-N 0.40 0.50 1.7 1.8 2.4 2.5 Ammonia-Nitrogen 0.18 0.21 0.62 0.48 1.21 1.39 Nitrate-Nitrogen 0.2 0.2 1.1 1.1 1.3 1.4 Total Phosphorus 0.24 0.17 0.29 0.48 0.62 0.63 Total Iron 0.35 0.32 0.42 2.8 6.6 10 Total Manganese 0.00 0.02 0.22 0.22 0.34 0.43 Total Coliform* 900 1,400 4,000 60,000 30,000 1,400 Fecal Coliform* 10 120 1,000 800 2,000 100 Fecal Strep* 100 <5 10 1,000 200 10

*Cells per 100 ml iron concentrations were consistently high during wet weather surveys.

Because flow volume was not recorded during the storm drain surveys these data can only be used for descriptive purposes. Qualitative analyses of the data demonstrate that storrnwater drainage entering the lake provided the major source of pollutants responsible for the cultural eutrophication of Spy Pond.

84 CONCLUSIONS

Spy Pond can be classified as a eutrophic lake. The high nutrient content has enhanced algal and aquatic macrophyte growth to an extent where the esthetic and recreational value of the Pond has become degraded. The following summary of results also support this conclusion:

a) The hypolimnion became anoxic during the summer stratification period.

b) Very high chlorophyll _a concentrations and large populations of phytoplankton were found in the trophogetiic zone.

c) Water transparency was very low.

d) Dense aquatic macrophyton growth and filamentous algae existed in certain areas of the littoral zone.

Results showed that a major source of nutrients causing the eutrophic conditions at Spy Pond was from the stormwater runoff entering the lake. The feasibility study will further address this problem quantitatively as well as qualitatively.

This study also suggested that the sediments provided a second source of* nutrients to the lake. Nutrients which accumulated in the hypolimnion during summer stratification were circulated throughout the water during fall over-K turn. This caused a significant increase in the nutrient concentration in \ the trophogenic zone that resulted in increased productivity.

In addition to being rich in nutrients, the stormwater runoff contained high levels of bacteria, especially during the first flush period. The results of the sanitary survey showed that coliform bacteria existed within the peri- phery of the lake even during dry weather.

85 REFERENCES

1. American Public Health Association, 1976. Standard Methods for the Examination of Water and Wastewater. 14th Edition, New York.

2. Arlington Redevelopment Board. 1973. Arlington, Massachusetts Comprehensive Flan Report. Arlington, Massachusetts.

3. Balazs, E. 1973. Spy Pond Stories.Tek/Komp, Arlington, Massa- chusetts .

4. Qiesebrough, E.W. and A.J. Screpetis. 1978 Lake Mattawa Water Quality Study. Massachusetts Division of Water Pollution Control, Westhorough, Massachusetts.

5. Chesebrough, E.W. and A.J. Screpetis 1978.' Fontoosuc Lake Water Qua1itv_Study. Massachusetts Division of Water Pollution Control, Westborough, Massachusetts.

6. Chesebrough, E.W., A.J. Screpetis, and P.M. Hogan 1976. Baseline Water Quality Surveys of Selected Lakes and Ponds in the Housatonic River Basin, Berkshire Cj3unt.y. Massachusetts Division of Water Pollution Control, Westborough, Massachu- setts. 7. Chute, N.E. 1959. Glacial Geology 'of the Mystic Lakes - Fresh Fond Ajrea, Massachusetts. Geological Survey Bulletin 1061-F, United States Government Printing Office, Washington, D.C.

8. Commonwealth of Massachusetts. 1953. Special Report of the Metropolitan Distric Commission of the Sanitary Condition of Spy Pond in the Town of Arlington. House Document No. 2208.

9. Commonwealth of Massachusetts, Department of Public Health. 1969. State Sanitary Code^ Article VII, Minimum Staridard for battling Beaches. Boston, Massachusetts-

10. Commonwealth of Massachusetts,Division of Water Pollution Control. 1977. Water Quality Monitoring Program of the Metropolitan .Area Planning Councils' 208 Management Aj^ea. Westborough, Massachusetts.

11. Commonwealth of Massachusetts, Department of Commerce and Develop- ment. 1978. Massachusetts Community Data. Boston, Massa- chusetts.

12. Commonwealth of Massachusetts, Division of Water Pollution Control., 1978. Massachusetts Water Quality Standards. Boston, Massachusetts.

86 13- Commonwealth of Massachusetts, Division of Fisheries and Wildlife. 1980. Information held in files at Field Headquarters, Westborough., Massachusetts.

14. Cortell, Jason M. and Associates. 1973. Report of Conditions in Spy Pond, Arlington, Massachusetts; A Historical Synopsis. Wellesley Hills, Massachusetts.

15. Cutter, B. and W.R. Cutter. 1880. History of the Town of Arling^ ton, Massachusetts. David Clapp and Son, Boston, Massa- chusetts.

16. Dillon, P. J. 1974. Manual for Calculating the Capacity of a ' Lake for Development. Ontario Ministry of Environment, Water Resources Branch, Ontario, Canada.

17. Fassett, N.C. 1957. A Manual of Aqjuatic^ Plants. University of Wisconsin Press, Madison.

18. - Garloff, G.C. and F. S. Koog. 1957. Availability of Iron and Manganese in Southern Wisconsin Lakes for the Growth of Microcvstis aeruginosa. Ecology, 38:551-556.

19. Habitat, Incorporated. 1972. Proposal to Study the Eutrophication Problem of Spy Pond. Belmont, Massachusetts.

20. Ham, J.D. 1975. Study and Interpretation of the Chemical Charac- teristics of Natural Water. 2nd Edition. United States Government Printing Office, Washington, D.C.

21. Hotchkiss, N. 1972. Common Marsh, Underwater, and Floating- Leaved Plants of the United States and Canada. Dover Publications, Inc., New York.

22. Hutchison, G.E. 1957. Geography and Physics of Lakes. Volume I, Part 1 in A Treatise on Limnology. John Wiley and Sons, Inc., New York.

23. __-1957* Chemistry of Lakes Vol. 1, Part 2, in A Treatise on Limnology. John Wiley and Sons, Inc., New York.

24. Hynes, H.B.N. 1974. The Biology of Polluted Waters. University of Toronto Press, Toronto, Ontario, Canada.

25. Kimball, W.A. 1979. Chlorophyll a Procedure. Massachusetts Division of Water Pollution Control, Westborough, Massachu- setts, (unpublished memorandum).

26. Langelier, W.F. 1936. The Analytical Control of Anti-Corrosion Water Treatment. J. Am. Water Works Assoc. 28:1500.

87 27. Lazaro, T.R. 1979. Urban Hydrology. Ann Arbor Science Publishers, Inc., Ann Arbor, Michigan.

28. MacConnell, W.P. 1972. Massachusetts Map Down Land Use and Vegeta- tive Cover Mappitig^ Lexington, Massachusetts. University of Massachusetts* Amherst, Massachusetts,

29. Maine Department of Environmental Protection, Division of Lakes and Biological Studies. 1974. Standard Procedures for Biological Evaluation. Augusta, Maine.

30. Mance, G. and M.M.I. Harman. 1978. The Quality of Urban Storm Runoff (pages 603-617). In P.R. Helliwell, ed. Urban Storm Drainage. John Wiley and Sons, New York.

31. McVoy, R.S. 1980. Baseline Water Quality Studies of Selected Lakes and Ponds in the North River Basin. Massachusetts Division of Water Pollution Control, Westborough, Massachu- setts,

32. Metropolitan Area Planning Council 1978. Area Wide Waste Treatment Management Plan. 208 Report Part I, Volume II. Boston, Massa- chusetts.

33. Odum, E.P. 1959. Fundamentals of Ecology. W.B. Saunders Co., Philadelphia, PA.

34. Olivieri, V.P. 1980. Microorganisms from Nonpoint Sources in the Urban Environment. In Environmental Impact of Nonpoint Source Pollution. Ed. M.R. Overcash and J.M. Davidson. Ann Arbor Science Publishers Inc., Ann Arbor, Mich.

35. Parker, C.S. 1907. Town of Arlington - Past and Present. C.S. Parker and Son, Aalington, Massachusetts.

36. Patrick, R. , B. Crum, and J. Coles. 1969. Temperature and Manga- nese as Determining Factors in the Presence of Diatom or Blue-green Algal Floras in Streams. Proc. Nat^Acad. Sci. 64:472-478.

37. Plotkin, S. and ti.M. Ram. 1982. Establishment of an Algal Assay Laboratory^: Progre_ss jteport to the Massachusetts DivisjLon of Water Pollution Control. Environmental Engineering Department of Civil Engineering, University of Massachusetts, Amherst.

38. Prescott, G.W. 1954., The Freshwater Algae. W.C, Brown Company Pub., Dubuque, Iowa.

39. Prescott, G.E. 1969. The Aquatic Plants. W.C. Brown Company Pub., Dubuque, Iowa.

40. Sawyer, C.H. 1960. Chemistry for Sanitary Engineers. McGraw-Hill Book Co., New York.

41. Sawyer, C.N. and P.L. McCarty. 1967. Chemistry for Sanitary Engineers. 2nd Edition. McGraw-Hill Book Company, New York.

88 42. Smith, G.M. 1950. Fresh-Water Algae of the United States. McGraw- Hill Book Co., New York.

43. Snaeyink. V.L. and D. Jenkins. 1980. Water Chemistry. John Wiley and Sons, New York.

44. Thoreau, H.D. 1854. Walden and Civil Disobedience. Authoritative Texts Background Reviews and Essays in Criticism, Owen Thomas. ed. W.W. Norton and Company, Inc., New York.

45. United States Department of Agriculture. 1978. Water and_Related Land Resources of the Coastal Region - jtessachusetts. Boston, Massachusetts.

46. United States Department of Commerce, Bureau of the Census. 1972. 1970 Census of Population General Social and Economic Charac- teristics - Massachusetts. U.S. Government Printing Office, Washington, D.C.

47. United States Department of Commerce, Bureau of the Census. 1981. I960 Census of Population and Housing - Massachusetts.

48. United States Department of Commerces Environmental Data and Informa- tion Service. 1980-1981. Climatological Data (monthly records) National Climatic Center, Asheville, North Carolina.

49. U.S. Environmental Protection Agency. 1973. Measures fot^ the Res- toration_and Enhancement of Quality of Freshwater Lakes. United States Government Printing Office, Washington, D.C.

50. United States Environmental Protection Agency. 1976. Quality Criteria for Water. United States Government Printing Office, Washington, D.C.

51. United States Environmental Protection Agency. 1978. Environ- mental Impact Statement on tjie^Upgrading of the Boston Metropolitan Area Sewerage System. Volume one, Boston, Massachusetts.

52. United States Environmental Protection Agency. 1979. Methods for Chemical Analysis of Water and Wastes. Environmental Monitoring and Support Laboratory, Cincinnati, Ohio.

53. Vollenweider, R.A. and J.A. Kerekas. 1980. jjackground^ and Summary Results of the Organization for Economic Cooperation and Development Cooperative Program on Eutrophication. United States Environmental Protection Agency, Washington, D.C.

54. Weber, C.I. 1974. Biological indicators of the trophic status of lakes. From a symposium on Biological Indicators _f_ o;r Assessing jJater Pollution. Newton, Massachusetts.

55. Welch, P.C, 1948. Limnological Methods. McGraw-Hill Book Co., New York.

.56. Wetzel, R.G. 1975. Limnology. W.B. Saunders Co., Philadelphia, PA.

89 APPENDIX A

CHLOROPHYLL a, PROCEDURES

I. Reagents and apparatus A. Flonrometer 1. "Blue lamp" Turner No. 110-853 2. Excitation Filter: Corning CS-5-60, #5543, 2 in", 4.9 mm polished ? 3. Emission Filter: Corning CS-2-64, #2408 2 in , 3.0 ran polished 4. R-136 photo multiplier tube B. Tissue grinder and tube C. Vacuum flask and pump D. Millipore filter holder E. Glass fiber filters: Reeve Angel, grade 934AH, 2.1 cm. F. Centrifuge (Fisher Scientific Safety Centrifuge) G. 15 ml graduated conical end centrifuge tubes with rubber stoppers H. 90% acetone I. 1 N HC1 (11.1 dilution of distilled water to cone. HC1) J. Saturated Magnesium Carbonate solution in distilled H.O II. Procedure A. Filter 50 ml (or less if necessary) of sample through glass fiber filter under vacuum B. Push the filter to the bottom of tissue grinding tube C. Add about 3 ml of 90% acetone and 0.2 ml of the MgCO solution D. Grind contents for 3 minutes E. The contents of the grinding tube are carefully washed into a 15 ml graduated centrifuge tube F. Q.S. to 10 ml with 90% acetone G. Tubes are then centrifuged for 20 minutes and the supernatent decanted immediately into stoppered test tubes. H. Test tubes are wrapped-with aluminum foil and stored in the refrigerator for 24 hours.

90 APPENDIX A (CONTINUED)

Chlorophyll _a Page 2

The tubes are allowed to come to room temperature, the temperature recorded, the samples poured into cuvettes, and then the samples are read on the fluorometer. (The fluorometer must be warned up for at least % hr. before taking a reading.) 0.2 ml of the 1 N HC1 solution is added to the sample in the cuvette, the cuvette stoppered and inverted and righted 4 times to mix thoroughly, and the sample is read again Both values are recorded, along with the window orifice size and whether the high-sensitivity or the regular door was used

91 ' B - TABLE I SPY POND TEMPERATURE (°C) - DISSOLVED OXYGEN (mg/1) - SATURATION (%) DATA STATION 1

DEPTH 3/20/80 3/24/80 4/9/80 5/12/80 5/27/80 7/1/80 (meters) TEMP . D.O. SAT. TEMP . D.O. SAT. TEMP . D.O. SAT. TEMP. D.O. SAT. TEMP. D.O. SAT. TEMP . D.O. SAT Surface 4.5 12.1 93 5.0 12.5 97 9.0 13.5 116 16.0 10.6 106 18.5 11.5 121 22.0 10.8 122 1 4.5 12.1 93 5.0 12.4 96 8.5 — — 15.0 18.5 11.5 121 22.5 9.9 113 — 2 4.5 12.1 93 5.0 12.3 96 8.5 12.5 106 15.0 10.8 105 18.5 11.5 121 22.5 10.0 114 3 4.5 12.1 93 5.0 12.2 95 8.5 14.5 18.0 10.5 110 22.5 9.9 113 — — 4 4.5 12.1 93 5.0 12.1 94 8.0 12.9 108 14.5 10.7 103 15.0 9.9 97 20.5 4.9 53 5 4.0 12.2 93 5.0 12.1 94 8.0 — 13.5 12.5 5.9 55 16.5 5.1 52 — — 6 4.0 12.2 93 5.0 12.0 93 8.0 12.3 103 12.0 6.7 62 10.5 4.5 40 15.0 2.6 25 7 4.0 12.2 5.0 12.0 8.0 11.0 9.0 2.2 18 12.5 1.4 13 93 93 — — — 93 11 0 8 4.0 12.2 93 5.0 12.0 7.5 12.2 — 9.5 3.5 30 8.0 1.4 10.5 0.0 2 0 9 4.0 12.1 92 5.0 12.0 93 7.0 — — 8.5 7.0 0.3 0.0 10 4.0 12.0 91 5.0 12.0 93 7.0 11.8 96 8.0 2.3 19 7.0 0.4 3 8.0 0.0 0

7/14/80 7/21/80 7/28/80 8/4/80 8/11/80 DEPTH 7/7/80 (meters) TEMP . D.O. SAT. TEMP . D.O. SAT. TEMP . D.O. SAT. TEMP. D.O. SAT . TEMP . D.O. SAT. TEMP . D.O. SAT Surface 23.5 10.3 119 25.0 10.0 119 29.0 8.3 106 A 7.2 28.0 8.0 101 26.5 7.4 90 1 23.5 9.5 24.5 10.0 118 27.5 8.2 102 6.8 — 27.5 8.0 100 26.5 7.4 90 110 — • 8.0 100 92 2 23.0 9.7 111 24.5 10.0 118 27.5 8.3 103 — 6.9 27.5 26.5 7.5 3 22.0 8.7 98 23.5 8.3 96 26.0 7.9 96 — 6.6 26.5 6.8 83 26.5 7.4 90 4 19.5 • 3.2 20.5 1.5 16 20.0 2.3 25. 2.0 21.5 1.3 14 21.0 6.3 70 34 — 8 0.3 3 8 5 16.0 2.9 29 16.5 0.5 5 17.0 0.8 — 1.9 17.0 16.5 0.8 13.0 1 6 12.5 0.2 1 13.0 0.3 2 13.0 0.7 6 — 0.9 13.5 0.3 2 0.1 7 10.0 0.0 11.0 0.2 10.5 0.0 0 0.0 12.0 0.0 0 11.0 0.0 0 0 1 — 8 9.0 0.0 9.5 0.0 9.5 0.0 0 0.0 10.0 0.0 0 9.5 0.0 0 0 0 — 0 9 8.5 0.0 0 8.5 0.0 0 8.5 0.0 0 — 0.0 — 9.5 0.0 0 8.5 0.0 10 8.0 0.0 8.0 0.0 8.0 0.0 0 0.0 8.5 0.0 0 8.5 0.0 0 0 0 — *Malfunction of thermistor probe APPENDIX B - TABLE 1 (CONTINUED)

8/18/80 DEPTH 8/25/80 9/22/80 10/23/80 10/29/80 (meters) TEMP. D.O. SAT. TEMP.- D.O. SAT. TEMP. D.O. SAT. TEMP. D.O. SAT. TEMP. D.O. SAT. Surface 24.0 8.8 103 23.5 9.0 104 21.0 8.5 94 12.0 7.2 67 10.0 6.9 61 1 24.0 8.8 103 23.0 9.2 106 20.5 A — 12.0 7.1 66 10.0 6.6 58 2 23.5 8.9 104 21.5 9.5 107 20.0 8.6 94 12.0 7.1 66 10.0 6.5 58 3 23.0 8.2 94 21.0 9.4 104 19.0 8.3 88 12.0 7.2 67 10.0 6.5 58 4 22.5 6.9 79 20.5 7.4 81 19.0 7.5 80 12.0 7.1 66 10.0 6.6 58 5 16.0 2.0 20 18.0 4.8 50 17.5 6.8 71 12.0 7.3 68 9.5 6.5 57 6 13.0 2.7 25 13.0 2.9 27 12.0 2.5 23 12.0 7.2 67 9.5 6.4 56 7 11.0 0.9 8 11.0 0.3 8 9.5 0.2 2 12.0 6.4 59" 9.5 6.1 53 8 10.0 0.0 0 10.0 0.0 0 8.0 0.0 0 11.5 5.7 52 9.5 * 9 8.5 0.0 0 8.5 0.0 0 7.5 0.0 0 9.0 0.0 0.0 9.5 6.3 55 10 8.5 0.0 0 8.5 0.0 0 7.0 0.0 0 9.0 0.0 0.0 9.5 6.5 57 11/13/80 1/13/81** 2/25/81*** 3/19/81 4/6/81 DEPTH (meters) TEMP. D.O. SAT. TEMP. D.O. SAT. TEMP. D.O. SAT. TEMP. D.O. SAT. TEMP. D.O. SAT. Surface 6.5 10.8 85 0.0 13.8 94 4.0 11.9 91 3.0 12.7 94 10.0 — 1 6.5 10.9 86 4.0 12.9 98 4.0 11.9 91 3.0 12.7 94 1010 10.8 96 2 6.5 11.0 87 4.0 12.9 98 4.0 12.3 94 3.0 12.7 94 10.0 10.6 94 3 6.5 10.8 85 4.5 12.2 94 4.0 12.0 92 3.0 12.5 9.3 10.0 10.6 94 4 6.5 10.7 84 4.0 — — • 4.0 11.9 91 3.0 12.7 94 10.0 10.6 94 5 6.5 10.8 85 4.5 11.8 91 4.0 11.8 90 3.0 12.6 93 10.0 10.8 96 6 6.5 10.6 84 4.5 11.7 90 4.0 10.8 82 3.0 12.6 93 10.0 10.5 93 7 6.5 10.7 84 4.0 9.7 74 4.5 9.4 73 3.0 12,4 92 9.5 10.5 92 8 6.5 10.7 84 4.0 9.8 75 4.5 6.2 48 3.0 12.5 93 9.5 10.5 92 9 6.5 10.8 85 4.0 8.8 67 4.5 6.0 46 3.0 12.5 93 8.0 9.6 81 10 6.5 10.9 86 4.0 9.2 70 . 5.0 3.0 23 3.0 12.6 93 7.0 9.0 74 *Sample broken in transit **Under 12 inches of ice ***Soon after ice-out which occurred between 2nd and 3rd week of February APPENDIX B - TABLE II SPY POND TEMPERATURE (°C) - DISSOLVED OXYGEN (mg/1) - SATURATION (%) DATA STATION 2 3/24/80 4/9/80 5/12/80 5/27/80 7/1/80 DEPTH 3/2°/8° (meters) TEMP. D.0. SAT. TEMP. D.O. SAT, TEMP. D.O. SAT. TEMP. D.O. SAT. TEMP. D.O. SAT, TEMP. D.O. SAT,

Surface 5.0 12.3 96 6.0 12.2 97 9.0 12.8 110 16.5 10.4 105 19.5 10.8 1.17 21.5 9.2 103 1 5.0 12.4 96 6.0 12.2 97 9.0 — 1.5.5 19.5 — -- 22.0 8.3 94 — 2 5.0 12.5 97 5.5 12.1 95 8.5 12.7 108 15.5 10.5 103 19.5 11.3 121 22.0 8.5 96 3 5.0 12.6 98 5.0 12.2 95 8.5 14.5 19.5 21.5 8.2 92 — — — — 4 5.0 12.6 98 5.0 12.2 95 8.5 12.7 108 14.5 9.2 89 14.5 6.8 66 19.5 5.0 53 5 5.0 12.5 97 5.0 12.2 95 8.5 — 13.5 — 13.0 — 16.5 1.5 15 — — 6 5.0 12.5 97 — — — 12.0 8.4 77 12.0 4.1 37 14.0 1.5 14 — — —

7/7/80 7/14/80 7/21/80 7/28/80 8/4/80 8/11/80 DEPTH (meters) TEMP . D.O. SAT. TEMP . D.O. SAT. TEMP . D.O. SAT. TEMP. D.O. SAT. TEMP . D.O. SAT. TEMP . D.O. SAT

Surface 23.5 10.1 117 25.5 9.5 114 28.5 7.4 94 * 6.4 28.0 7.8 98 26.0 7.4 90 1 23.5 8.6 100 25.5 9.0 108 27.5 • 7.3 89 6.1 27.0 7.7 95 26.0 7.3 89 2 21.5 8.8 98 24.5 8.6 101 27.0 6.1 75 6.4 26.5 7.8 96 26.0 7.3 89 3 18.5 2.9 30 22.5 5.6 64 24.0 5.9 69 4.1 — 24.5 5.2 61 25.0 6.5 77 4 15.0 3.1 30 18.5 1.6 8 18.5 0.8 8 0.8 21.0 5.1 56 20.0 3.1 33 5 13.0 3.3 31 15.0 0.3 2 16.0 0.5 5 0.6 — 16.0 0.0 0 15.5 0.0 0 6 12.5 0.0 0 13.5 0.0 0 14.0 0.0 0 0.0 14.5 0.0 0 13.5 0.0 0

*Malfunction of thermistor probe APPENDIX B - TABLE II (CONTINUED)

8/11/80 DEPTH 8/25/80 9/22/80 10/23/80 (meters) TEMP. D.O. SAT- TEMP. D.O. SAT. TEMP. D.O. SAT, TEMP. D.O. SAT Surface 25.0 9.4 Ill 24.5 10.0 118 21.0 8.4 93 12.0 9.2 85 1 ' 23.5 9.6 112 23.5 10.3 120 20.5 8.7 96 12.0 8.9 82 2 23.0 8.9 102 22.0 10.2 115 19.5 8.3 89 12.0 8.7 81 3 23.0 7.3 84 21.0 8.3 92 19.0 7.6 81 12.0 8.8 82 4 22.0 5.1 58 20.5 7.8 86 18.5 6.7 71 12.0 8.7 81 5 16.0 0.5 5 18.0 6.4 67 18.0 4.8 50 12.0 8.6 80 6 14.0 0.1 1 14.0 0.0 0 14.0 0.9 9 12,0

10/29/80 11/13/80 2/25/81* DEPTH 3/19/81 (meters) TEMP. D.O. SAT TEMP. D.O. SAT. TEMP. P.O. SAT, TEMP. D.O. SAT, Surface 9.5 8.2 72 6.0 11.2 90 5.0 11.6 91 3.5 12.4 93 1 9.5 8.3 72 6.0 11.0 88 5.0 12.0 94 3.5 12.5 94 Ui 2 9.5 8.5 74 6.0 11.3 90 5.0 12.4 97 3.5 12.5 94 3 9.5 8.0 70 6.0 11.1 89 5.0 12.2 95 3.5 12.5 94 4 9.5 8.2 72 6.0 11.1 89 5.0 12.0 94 3.5 12.5 94 5 9.5 8.1 71 6.0 11.0 88 4.5 11.8 91 3.5 12.5 94 6 9.5 8.1 71 6.0 11.0 88 4.0 10.3 79 3.5 12.2 92

ASoorv after ice-out which occurred between 2nd and 3rd week of February APPKNOIX JJ - TABLE III SPY POND - ROUTE 2 INLET RESULTS OF CHEMICAL ANALYSES (mg/1)

PARAMETER 3/12/80 3/20/80 3/24/80 4/1/80 4/9/80 4/14/80 4/22/80 4/28/80 5/8/80 5/12/80 5/19/80 pH (Standard Units) 7.6 7.7 7.2 7.7 7.7 8.2 7.3 6.7 7.6 7.7

Total Alkalinity 49 48 44 47 24 46 46 — Total Hardness 166 233 130 105 55 102 100 — Conductivity 920 - 1,200 720 620 410 300 600 580 (pmhos/cm)

Chlorides 240 365 305 145 11 104 120 75 64 125 120

Suspended Solids 1.0 3.5 0.5 3.5 5.5 16 0.0 1.5

Total Solids 650 948 466 386 264 254 366 348

Total Kjeldahl-N 0.71 0.92 1.4 1.1 0.85 11.0 0.85 1.1 1.2 0.62 0.29

Ammonia-Nitrogen 0.08 0.18 0.09 0.10 0.12 0.06 0.15 0.11 0.03 0.14 0.10

Nitrate-Nitrogen 1.6 1.5 1.8 1.6 1.8 1.6 1.8 1.3 1.2 1.7 0.18

Total Phosphorus 0.04 0.04 0.01 0.08 0.04 0.08 0.09 0.08 0.29 0.06 0.10

Total Iron 0.10 0.04 0.00 0.06 0.03 0.07 0.07 — 0.02 __ — 0.03 0.02 Total Manganese 0.05 0.02 — — APPENDIX B - TABLK 111 (CONTINUED)

PARAMETER 5/27/80 6/3/80 7/1/80 7/7/80 7/14/80 7/21/80 7/28/80 8/4/80 8/11/80 8/18/80 pH (Standard Units) 6.9 7.7 8.8 8.3 7.7 7.7 7.2 7.4 7.7 7.6

Total Alkalinity 4 45 89 59 55 26 22 52 50 59

Total Hardness 101 71 102 91 110 106 42 95 105 113

Conductivity (umhos/cm) 580 560 590 675 680 730 250 630 640 700

Chlorides 130 112 124 146 155 120 46 130 140 100

Suspended Solids 0.0 10 1.5 0.0 1.0 1.5 0.0 1.0 4.5 0.5

Total Solids 336 372 472 410 592 402 144 310 372 374

Total Kjeldahl-N 0.28 0.39 0.58 0.72 0.61 0.63 10.44 0.55 0.34 0.50

Ammonia-Nitrogen 0.14 0.39 0.28 0.16 0.15 0.06 0.14 0.24 0.06 0.13

Nitrate-Nitrogen 1.8 '1.8 1.7 1.6 1.6 1.6 0.7 2.1 1.9 2.6

Total Phosphorus 0.07 0.12 0.15 0.10 0.12 0.07 0.05 0.13 0.11 0.11

0.10 0.21 0.08 0.07 0.02 0.01 0.09 0.06 0.06 Total Iron — 0.01 0.03 0.01 0.02 0.00 0,01 0.13 0.03 0.05 Total Manganese — APPENDIX B - TABLE III (CONTINUED)

PARAMETER 8/25/80 9/22/80 10/23/80 10/29/80 11/13/80 1/13/81 2/11/81 2/18/81 2/25/81 3/19/81 pH (Standard Units) 7.5 7.0 7.8 7.4 8.1 7.5 6.9 6.6 6.7 7.0

Total Alkalinity 38 57 63 62 63 53 14 16 6.0 18

Total Hardness 93 95 107 101 84 78 25 64 — — Conductivity (pmhos/cm) 720 600 630 600 580 960 860 450 250 . 390

Chlorides 140 135 130 120 115 260 250 113 65 95

Suspended Solids 1.5 5.0 0.0 0.5 4.0 — 133 1.0 30 2.0 Total Solids 454 348 396 384 330 — 672 286 200 250

Total Kjeldahl-N 0.60 0.56 0.47 0.98 1.1 0.51 1.9 0.71 0.42 0.34

Ammonia-Nitrogen 0.07 0.03 0.04 .0.12 0.15 0.08 0.08 0.14 0.16 0.32

Nitrate-Nitrogen 1.6 1.4 1.5 1.8 2.5 1.4 0.7 0.6 0.7 1.1

Total Phosphorus 0.08 0.05 0.08 0.14 0.32 0.06 0.40 0.06 0.08 0.05

Total Iron 0.11 0.02 0.03 0.09 0.07 — — 0.06 0.08 0.12 0.02 0.01 0.01 0.02 0.03 — 0.03 0.01 0.03 Total Manganese — APPENDIX B - TABLE IV SPY POND - OUTLET RESULTS OF CHEMICAL ANALYSES (mg/1)

PARAMETER 3/12/80 3/20/80 3/24/80 4/1/80 4/9/80 4/14/80 4/22/80 4/28/80 5/8/80 5/12/80 pH (Standard Units) 7.4 7.6 7.5 7.8 7.8 7.8 7.5 7.2 7.7

Total Alkalinity .34 35 33 —_ 1J L9. 31 31

Total Hardness 68 64 67 70 69 65

Conductivity (probes/cm) 520 480 490 480 440 450

Chlorides 122 122 118 120 118 114 100 110 100

Suspended Solids 3.0 3.5 2.5 5.0 2.5 — Total Solids 308 312 362 342 382 362

Total Kjeldahl-N 0.58 0.89 1.0 1.2 2.1 1.2 1.4 0.98 0.93 0.72

Ammonia-Nitrogen 0.09 0.32 0.32 0.16 0.04 0.09 0.16 0.16 0.03 0.06

Nitrate-Nitrogen 0.2 0.4 0.5 0.5 0.4 0.5 0.6 0.05 0.5 0.5

Total Phosphorus 0.02 0.02 0.01 0.05 0.06 0.06 0.05 0.13 0.06 0.05

Total Iron 0.10 0.06 0.00 0.8 0.14 0.10

Total Manganese 0.05 0.02 0.05 — • — — ~ .' 0.02 APPENDIX B - TAIJU! IV (CONTINUED)

PARAMETER 5/19/80 5/27/80 6/3/80 7/1/80 7/7/80 7/14/80 7/21/80 7/28/80 8/4/80 8/11/80 8/18/80

pH (Standard Units) 7.8 6.8 7.4 7.5 9.3 9.3 8.9 7.7 7.8 7.5 7.8

Total Alkalinity 31 7 32 32 32 31 34 30 30 28 39

Total Hardness 67 66 54 64 49 64 67 69 63 64 63

Conductivity 460 450 470 440 482 460 470 470 440 440 430 (^mhos/cm)

Chlorides 95 115 106 102 110 110 120 110 110 99 25 4.5 8.5 18 Suspended Solids 4.5 5.5 4.5 12 18 14 9.5 — Total Solids 326 310 358 406 306 290 322 354 250 304 264 g Total Kjeldahl-N 0.60 0.55 0.13. 1.2 1.3 1.2 0.98 0.81 0.67 0.69 1.4

Ammonia-Nitrogen 0.02 0.01 0.09 0.04 0.01 0.01 0.02 0.01 0.02 0.01 0.00

Nitrate-Nitrogen 0.5 0.4 0.3 0.1 0.0 0.1 0.0 0.0 0.0 0.0 0.0

Total Phosphorus 0.06 0.07 0.04 0.72 0.08 0.11 0.04 0.10 0.07 0.09 0.14

0.13 0.22 0.12 0.16 0,04 Total Iron 0.05 0.12 — 0.18 0.22 0.10

Total Manganese 0.01 0.05 0.06 0.06 0.04 0.04 0.06 0.05 0.05 0.03 APPENDIX B - TABLE IV (CONTINUED)

PARAMETER 8/25/80 9/22/80 10/23/80 10/29/80 11/13/80 2/18/81 2/25/81 3/19/81 pH (Standard Units) 7.6 7,7 7-5 6,9 7,7 6,7 7,4 7,4

Total Alkalinity 41 34 37 36 40 23 28 32

Total Hardness — 67 85 69 66 44 42 66

Conductivity (pmhos/cm) 450 450 440 430 430 320 420 480

Chlorides 100 110 90 95 100 69 105 115

Suspended Solids 4.0 9.5 22* 5.0 3.0 3.0 5.0 2.0

Total Solids 314 292 300 296 238 198 280 350

Total Kjeldahl-N 1.5 0.98 1.6 1.4 2.3 0.60 0.79 0.70

Ammonia-Nitrogen 0.01 0.00 0.12 0.32 0.42 0.08 0.17 0.21

Nitrate-Nitrogen 0.0 0.0 0.1 0.1 0.1 0.3 0.3 0.4

Total Phosphorus 0.05 0.06 0.11 0.10 0.46 0.05 0.06 0.06

Total Iron 0.08 0.04 0.06 0.03 0.04 0.02 0.01 0.05

Total Manganese 0.04 0.02 0.05 0.04 0.04 0.01 0.00 0.03

*Probable contamination from bottom sediment APPENDIX C - TABLE I SPY POND MICROSCOPIC EXAMINATION (cells per ml) STATION 1 DATE BACILLARIOPHYCEAE . CHLOROPHYCEAE CYANOPHYCEAE MASTIGOPHORA TOTAL 3/20/80 2,688 829 400 3,918 3/24/80 2,774 143 715 3,632 4/1/80 8,205 1,883 10,088 4/9/80 9,217 2,670 11,886 4/14/80 4,552 56 1,798 6,407 5/12/80 4,777 56 1,012 5,845 5/19/80 3,063 281 590 3,934 5/27/80 * A * A A o K) 7/1/80 18,333 833 833 19,999 7/7/80 34,166 5,833 833 40,832 7/14/80 22,499 5,000 833 28,332 7/21/80 14,999 5,000 833 20,832 7/28/80 8,333 6,666 14,999 8/4/80 5,833 1,666 833 8,333 8/11/80 8,333 833 9,166 8/18/80 2,698 1,040 365 4,046 8/25/80 2,108 225 140 2,473 9/22/80 56 3,272 3,328 10/23/80 2,051 3,288 1,012 ' 337 6,688 10/29/80 3,287 1,489 225 140 5,142 APPENDIX C - TABLE 1 (CONTINUED)

DATE BACILLARIOPHYCEAE CHLOROPHYCEAE CYANOPHYCEAE MASTIGQPHORA TOTAL

11/13/80 22,499 5,833 5,000 33,332 11/25/80 674 2,304 112 3,091 1/13/80 1,068 337 28 140 1,574 2/25/80 4,833 112 73,1 5,676 3/19/81 4,496 56 28 309 4,889 4/6/81 3,456 28 28 3,512

*Acld contamination of sample - unreliable data

o UJ APPENDIX C - TABLE II SPY PuND MICROSCOPIC EXAMINATION (cells per ml) STATION 2 DATE BACILLARIOPHYCEAE CHLOROPHYCEAE CYANOPHYCEAE MASTIGOPHORA TOTAL 3/20/80 3,260 343 572 4,176 3/24/80 5,034 172 458 5,663 4/9/80 8,290 28 2,164 10,481 4/14/80 2,838 28 1,574 4,440 5/12/80 7,278 169 927 8,374 5/19/80 5,198 169 365 5,732 5/27/80 1,405 534 28 478 2,445 7/1/80 20,999 2,500 1,667 24,166 7/7/80 31,666 6,666 10,832 49,165 7/14/80 26,666 4, 166 30,832 7/21/80 12,500 10,833 23,332 7/28/80 3,333 10,000 13,333 8/4/80 7,500 833 1,667 10,000 8/11/80 10,000 2,500 12,500 8/18/80 4,166 2,500 833 7,500 8/25/80 1,602 422 2,023 9/22/80 56 2,979 2,979 10/23/80 1,995 2,979 365 253 5,592 10/29/80 2,922 1,349 365 224 4,861 11/13/80 32,499 7,500 1,667 2,500 44,165 2/25/81 3,400 84 56 562 4,102 3/19/81 4,861 28 28 169 5,086 APPENDIX C - TABLE III SPY POND 3 CHLOROPHYLL-a DATA (mg/m )

DATE STATION 1 STATION 2

3/20/80 3.32 2.91 3/24/80 2.91 3.32 4/1/80 10.19 4/9/80 15.85 14.71 4/14/80 11.32 9.05 5/12/80 4.98 4.57 5/19/80 2.44 5.40 5/27/80 11.32 11.32 7/1/80 23.69 23.69 7/7/80 30.46 33.84 7/14/80 12.45 15.84 7/21/80 10.19 12.45 7/28/80 7.06 5.81 8/4/80 9.05 7.89 8/11/80 9.05 11.32 8/18/80 9.05 8.30 8/25/80 7.92 9.05 9/22/80 9.05 6.79 10/23/80 48.68 16.98 10/29/80 12.45 11.32 11/13/80 13.58 13.58 11/26/80 9.55 1/13/81 12.04 2/25/81 12.45 12.45 3/19/81 5.81 4.98 4/6/81 4.15

105 APPENDIX C - TABLE IV

SPY PONT PHYTOPLANKTON GENERIC IDENTIFICATION STATIONS 1 AND 2

BACILLARIQPHYCEAE CHLOROPHYCEAE CYANQPHYCEAE MASTIGOPHORA

Asterionella Arthrodesmus Anabaena Chiamydomonas Ceratoneis Chlorococcum Aphanizomenon Chroomonas Cocconeis Chlorosarcina Aphanocapsa Cryptochrys is Cyclotella Closteriopsis Coelosphaerium Cryptomonas Diatoma Closterium Chroococcus Euglena Fragilaria Coelastrum Merismopedia Haematococcus Gomphonema Cosmarium Microcystis Lepocinclis Mertdion Crucigenia Nostoc Lobomonas Navicula Cylindrocapsa Oscillatoria Merotrichia Pinnularia Dactylothece Spirulina Pandorina Stauroneis Desmidium Peridiniura Synedra Elakatothrix Pleodorina Tabellaria Gloeocystis Pyrobotrys Golenkinia T ra ch e1oraonas Gonium Mougeotia Oocystis Pediastrum Protococcus Quadrigula Rhizoclonium Scenedesmus Sphaerocystis Staurastrum Tetrapedia

106 APPENDIX D

A NOTE ON LIMNOLOGY AND LAKE RESTORATION PROJECTS

Limnology is the study of inland fresh waters, especially lakes >and ponds (lentic water vs. lotic water'for streams and rivers). The science encompasses the geological, physical, chenical, and biological events that operate together in a lake basin and are dependent on each other (Hutchinson, 1957)„ It is the study of both biotic and abiotic features that make up a lake's ecosystem. As pointed out by Dillon (1974) and others before him, in order to understand lake conditions, one must realize that the entire watershed and not just the lake, or the lake and its shoreline, is the basic ecosystem. A very important factor, and one on which the life of the lake depends, is the gravitational movement of minerals from the watershed to the lake. Admittedly, the report contained herein concentrates mainly on the lake itself. Yet the foremost problem affecting the lakes and ponds today is accelerated cultural eutrophication, which originates in the watershed and is translated into various non-point sources of pollution. A great deal of lake restoration projects will have to focus on shoreland and lake watershed management.

Hynes (1974) sums up the science well in stating:

...The conclusions...are therefore that any interference vith the normal condition of a lake or a stream is almost certain to have some adverse biological effect, even if, from an engineering point of view, the interference results in considerable improvement. At present it would seem that this is little realized and that often much unnecessary damage is done to river and lake communities simply because of ignorance. It is of course manifest that sometimes engineering or water-supply projects have over-riding importance and even if they have not, the question of balancing one interest against the other must often arise. But, regrettably, even the possibility of biological consequences is often ignored. It cannot be emphasized too strongly that when it is proposed to alter an aquatic environment the project should be considered from the biological ag well as the engineering viewpoint. Only then can the full implications of the proposed alteration be assessed properly, and a reasonable decision be taken. Obviously this will vary with the circumstances and the relative importance of the various consequences involved, but, at present, unnecessary and sometimes costly mistakes are often made because the importance of biological study is unknown to many administrators. Often, as for instance in drainage operations, it would be possible to work out compromises which would satisfy both engineering and biological interests. 1

1 Hynes, H.B.K., 1974. The Biology of Polluted Waters. University of Toronto Press, Toronto, Ontario, Canada.

107 EUTROPHICATION

aging by ecological succession

Oligotrophic lake

Mesotrophic lake

Pond, marsh, or swamp

Source: Measures for the Best oration and Enhancement cf Quality of Freshwater lakes. Washington, D.C.: United States Environmental Protection Agency, 1973.

FIGURE A

108 APPENDIX D (CONTINUED)

EUTROPHICATION

The term "eutrophic" means well-nourished; thus, "eutrophication" refers to natural or artificial addition of nutrients to bodies of water and to the effects of added nutrients (Eut roph ica11 on: Ca us e ST, Ccmseguenceg a nd Correc tives^. 1969) . The process of eutrophication is nothing new or invented by man. It is the process whereby a lake ages and eventually disappears. An undisturbed lake will slowly undergo a natural succession of stages, the end product usually being a bog and, finally, dry land (see Figure A). These stages can be identified by measuring various physical, chemical, and biological aspects of the lake's ecosystem. Kan can and often does affect the rate of eutrophication. From a pollutional point of view, these effects are caused by increased population, industrial growth, agricultural practices, watershed development, recreational use of land and waters, and other forms of watershed exploitation.

It might also be mentioned that some forms of water pollution are natural. Streams and ponds located in densely wooded regions may experience such heavy leaf fall as to cause asphyxiation of some organisms. Discoloration of many waters in Massachusetts is caused by purely natural processes. As pointed out by Hynes (1974) , it is extremely difficult to define just what is meant by "natural waters," which is not necessarily synonomous with "clean waters."

For restorative or preservative purposes of a lake and its watershed, it is important to identify both a lake's problem and the cause of the problem. Problems associated with eutrophication include nuisance algal blooms (especially blue-green algae), excessive aquatic plant growth, low dissolved oxygen content, degradation of sport fisheries, low transparency, mucky bottoms, changes in species type and "diversity, and others. The pollutional cause is identified as either point or non-point in origin. A point source of pollution may be an inlet to the lake carrying some waste discharge from upstream. Or it may be an industrial, agricultural, or domestic (e.g., washing machine pipe) waste discharge which can be easily identified, quantified, and evaluated.

Non-point sources of pollution, which are the more common type affecting a lake, are more difficult to identify. They include agricultural runoff, urban runoff, fertilizers, septic or cesspool leakage, land clearing, and many more. They are 'often difficult to quantify, and thus evaluate.

An objective of a lake survey Is to measure a lake's trophic state; that is, to describe the point at which the lake is in the aging process.. The measure most widely used is a lake's productivity. Technically, this involves finding out the amount of carbon fixed per meter per day by the primary producers. Since it is a rather involved procedure to determine the energy flow through a lake system, the lake survey attempts to indirectly describe the lake's trophic state or level of biological productivity.

During the process of eutrophication, a lake passes through three major broad stages of succession: oligotrophy, mesotrophy, and eutrophy. Each stage has its characteristics (Table I). Data from a lake survey can be analyzed for assessment of the lake's trophic state. Although the level of productivity is

109 APPENDIX D - TABLE I LAKE TROPHIC CHARACTERISTICS

1. Oligotrophic Lakes

a. ' Very deep, thennooline high; volume of hypolimnion large; water of hypolimnion cold.

b. Organic materials on bottom and in suspension very low.

c. Electrolytes low or variable; calcium, phosphorus, and nitrogen relatively poor; humic materials very low or absent.

d. Dissolved oxygen content high at all depths and throughout year.

e. Larger aquatic plants scarce.

f. Plankton quantitatively restricted; species many; algal blooms rare; Chlorophyceae dominant.

g. Profundal fauna relatively rich in species and quantity; Tanytarsus type; Corethra usually absent.

h. Deep-dwelling, cold-water fishes (salmon, Cisco, trout) common to abundant.

i. Succession into eutrophic type.

2. Eutrophic Lakes

a. Relatively shallow; deep, cold water minimal or absent.

b. Organic materials on bottom and in suspension abundant.

c. Electrolytes variable, often high; calcium, phosphorus, and nitrogen abundant; humic materials slight.

d. Dissolved oxygen in deep stratified lakes of this type minimal or absent in hypolimnion.

e. Larger aquatic plants abundant.

f. Plankton quantitatively abundant; quality variable; water blooms common, Myxophyceae and diatoms predominant.

g. Profundal fauna, in deeper stratified lakes of this type; poor in species and quantity in hypolimnion; Chironomus type; Corethra present.

110 APPENDIX D. - TABLE I (CONTINUED)

h. Deep-dwelling, cold water-fishes usually absent; suitable for perch, pike, bass, and other warm-water fishes.

i. Succession into pond, swamp, or marsh.

3. Dystrophic Lakes

a. Usually shallow; temperature variable; in bog surroundings or in old mountains.

b. Organic materials in bottom and in suspension abundant.

c. Electrolytes low'; calcium, phosphorus, and nitrogen very scanty; humic materials abundant.

d. Dissolved oxygen almost or entirely absent in deeper water.

e. Larger aquatic plants scanty.

f. Plankton variable; commonly low in species and quantity; Myxophyceae may be very rich quantitively.

g. Profundal macrofatma poor to absent; all bottom deposits with very scant fauna; Chironomus sometimes present; Corethra present,

h. Deep-dwelling, cold-water fishes always absent in advanced dystrophic lakes; sometimes devoid of fish fauna; when present, fish production usually poor.

i. Succession into peat bog.

Source: Welch, P.S., Limnology, McGraw Hill Book Co., New York, 1952. (Reprinted with permission of the publisher.)

Ill not quantified, the physical, chemical, and biological parameters measured go a long way in positioning the lake as to its trophic status. The perimeter survey helps locate and identify sources" of pollution, it should be noted, however, that at the present time, there is no single determination that is a universal measure of eutrophication.

Figure B shows the various zones of a typical stratified lake. In addition to the lake's life history mentioned above, a lake also has characteristic annual cycles. Depending on the season, a lake has a particular temperature and dissolved oxygen profile (Figure B). During the summer season, the epilimnion, or warm surface water, occupies the top zone. Below this is the metalimnion, which is characterized by a thermocline. In a stratified lake, this is the zone of rapid temperature change with depth. The bottom waters, or hypolimnion, contain colder water. The epilimnion is well mixed by wind action, whereas the hypolimnion does not normally circulate. During the spring and fall seasons, these regions break down due to temperature change and the whole lake circulates as one body. In shallow lakes (i.e., 10 to 15 feet maximum depth) affected by wind action, these zones do not exist except for short periods during calm weather,

The summer season (July and August) is the best time to survey a lake in order to measure its trophic status. This is the time when productivity and biomass are at their highest and when their direct or indirect effects can best be measured and observed. The oxygen concentration in the hypolimnion is an important characteristic for a lake. A high level of productivity in the surface waters usually results in low oxygen concentrations in the lake's bottom. Low oxygen in the hypolimnion can adversely affect the life in the lake, especially the cold-water fish which require a certain oxygen concentration. Organic material brought in via an inlet can also cause an oxygen deficit in the hypolimnion. Hutchinson (1957) has amply stressed the importance of dissolved oxygen in a lake.

A skilled limnologist can probably learn more about the nature of a lake from a series of oxygen determinations than from any other kind of chemical data. If the oxygen determinations are accompanied by observations on secchi disc transparency, lake color, and some morphometric data, a very great deal is known about the lake.

Nitrogen and phosphorus have assumed prominance in nearly every lake investigation in relating nutrients to productivity (eutrophication) . Some investigators (Odum, 1959) use the maximum nitrogen and phosphorus concentrations found during the winter as the basis of nutrient productivity correlation due to the biological minimum caused by environmental conditions. Others use data following the spring overturn as a more reliable basis for nutrient productivity correlation. In any event, considerable caution must be used in transporting nutrient concentration limits found in other lakes to the present situation.

112 THERMAL CHARACTERISTICS OF TEMPERATE LAKES

METAIIMNION (THE RMOC LINE)

SUMMER Dissolved Oiygen (mg/l) Q 246 8 10 12 14 0 2 4 6 8 10 12 14 0 24 6 8 10 12 1

1 I I 1 I 32 39 47 54 61 68 75 82 32 39 47 54 61 B8 75 82 32 39 47 54 61 68 75 82 Temperature "F STRATIFICATION ISOTHERMAL INVERSE STRATIFICATION

Saurce: Measures for the Restoration and Enhancement of Quality e< Freshwater l»hes. Washington D.C.: United States Environmental Protection Agency, 1973. FIGURE B

113 Table II depicts concentrations of various substances and other data for tvo hypothetical lakes, one eutrophic, the other oligotrophic.' It is intended as a guide for comparison to the data presented in this report. Each lake, of course, is different from all others. There is no hard and fast rule as to the critical concentrations for each lake. The morphology of a lake (e.g., mean depth) plays an important part in its general vell-being. A small, deep lake will react differently to nutrient loading than a large, shallow lake. In the final analysis, each lake is found unique and must be evaluated on an individual basis.

114 APPENDIX D - TABLE II

SELECTED DATA FOR TWO HYPOTHETICAL LAKES

CONCENTRATIONS IN

DISSOLVED OXYGEN TRANSPARENCY PHYTOPLANKTON AQUATIC CHARACTERISTIC TROPHIC STATUS AT BOTTOM (SECCHI LEVEL) NIU-N NOi-N TOTAL .P ASSEMBLAGES VEGETATION FISHERIES

Lake A High High Low Low Low High diversity, Sparse Cold water (Ollgotrophic) >5.0 <0.3 <0.3 <0.0l low numbers, types nearly complete absence of blue-greens.

Lake B Low Low High High High Low diversity, Abundant ' Warm-water (Eutrophlc) <5.0 >0.3 >0.3 >0.01 high numbers, types abundance of blue-greens.

1. Not established as State standards.

2, Ollgptrophlc " nutrient - poor Eutrophlc « high concentrations of nutrlenta APPENDIX E DESCRIPTION OF TERMS

The terms related to limnology and other limnological entities, as used in this report, are defined below to assist the reader in interpreting some of the data presented:

ADVECTION - the hydraulic mechanism by which water quality constituants are transported in the direction of the water flow.

ALLO C HT HONpUS - refers to compounds formed in the catchment basin which are brought into the body of water,

AQUATIC PLANTS - or aquatic macrophyton can be defined as those vascular plants which germinate and grow with at least their base in the water and are large enough to be seen with the naked eye. The following three broad categories are recognized:

1. Emergent types are those plants rooted at the bottom and pro- jecting out of the water for part of their length. Examples: arrowhead (Sagittaria spp.)» pickerelweed (Pontederia spp,)

2. floating types are those which wholly, or in part, float on the surface of the water and usually do not project above it. Example: water shield (Brasenia sp.)> yellow water lily (Nuphar sp.)

3. jubmerged types are those which are continuously submerged (except for possible floating or emergent inflorescences). Examples: bladderwort (Utricularia spp.), pondweed (Potamogeton spp.)

AREA - of a lake refers to the size of the surface, exclusive of islands measured in square units by planimetry.

ARGILLACEOUS - of, relating to, or containing clay or clay minerals.

AUTOCHTHONOUS - refers to compounds formed or activities done within the body of water.

BASE FLOW - stream discharge derived from groundwater sources.

CULTURAL EUTROFHICATION - refers to the enrichment or rapid increase in productivity of a body of water caused by man.. It is an accelerated process as opposed to natural, slow-aging of a body of water. Visual effects include nuisance algal blooms, low transparency, extensive aquatic plant growth, and loss of cold-water fisheries due to oxygen depletion. It is caused by the rapid increase in nutrient additions to a lake.

116 DEVELOPMENT OF SHORELINE - is the degree of regularity or irregularity of a shoreline expressed.as an index figure. It is the ratio of the length of the shoreline to the length of the circumference of a circle of an area equal to that of the lake. It cannot be less than unity. The quantity can be regarded as a measure of the potential effect of littoral processes on the lake.

DEVELOPMENT OF VOLUME - is defined as the ratio of the volume of the lake to that of a cone of basal area equal to the lake's area and height equal to the maximum depth.

DIMICTIC LAKE - is one with spring and fall turnovers (temperate lakes).

DISSOLVED OXYGEN (D.O.) - refers to the uncombined oxygen in water which is available to aquatic life; D.O. is, therefore, the critical parameter for fish propagation. Numerous factors influence D.O., including organic wastes, bottom deposits, hydrologic characteristics, nutrients, and aquatic organisms. Saturation D.O., or the theoretical maximum values, is primarily a function of temperature. D.O. values in excess of saturation are usually the results of algal blooms and, therefore, indicate an upset in the ecological balance. Optimum D.O. values range from 6.0 mg/1 (minimum allowable for cold water fisheries) to saturation values. The latter range from 14.6 mg/1 at 0°C (32°F) to 6.6 mg/1 at 40°C (104°F).

EPILIMNION - refers to the circulating, superficial layer of a lake or pond lying above the metalimnion which does not usually exhibit thermal stratification.

EUTROPHIC - generally refers to lakes which are rich in dissolved nutrients often with seasonal deficiencies in dissolved oxygen.

EVAPQTRANSPIRATION - the combined processes of evaporation from land, water, and other surfaces, and transpiration by plants. . .

GLACIAL TILL - nonsorted, nonstratified sediment carried or deposited by a glacier.

GNEISS - coarse-grained rock in which bands rich in granular minerals alter-. nate with bands in which schistose minerals predominate.

GRANTTE - plutonic rock consisting essentially of alkalai feldspar and quartz,

HARDPAN - is a hard impervious layer, composed chiefly of clay, cemented by relatively insoluble materials, does not become plastic when mixed with water, and definitely limits the downward movement of water and roots.

HECTARE (ha) - areal measurement equal to ten thousand square meters (10,000 m ).

HETEROGRADE - is a stratification curve for temperature or a chemical substrate in a lake which exhibits a non-uniform slope from top to bottom. It can be positive (metalimnetic maximum) or negative (metalimnetic minimum).

117 HYDROLOGICAL BUDGET - an accounting of all inflow to, outflow from, and changes in storage wit-hin a hydrologic unit such as a drainage basin, aquifer, or lake.

HYPEREUTROPHIC - generally refers to eutrophic lakes which are enriched with plant nutrients to the point where most of the nutrients are not used by organisms in the lakes.

HYPOLIMNION - refers to the deep layer of a lake lying below the metalimnion and removed from surface influences (i.e., not circulating).

jCILOMETER - linear measurement equal to one thousand meters (1,000 m).

LEACHATE - the liquid that has percolated through the soil or other media and has extracted dissolved or suspended materials from it.

LENTIC - refers to still or calm water, such as lakes or ponds.

LITTORAL ZONE - consists of the shallow waters of a body of water. They often form an interface zone between the land of the drainage basin and the open waters of the body of water.

LOADING - the dry weight or same material that is being added to a process or disposed of.

LQTIC - refers to moving water, such as rivers or streams.

MAXIMUM DEPTH - is the maximum depth known for a lake.

MAXIMUM EFFECTIVE LENGTH - is the length of a straight line connecting the most remote extremities of a lake along which wind and wave action occur without any kind of land interruption. It is often identical with maximum length.

MAXIMUM EFFECTIVE WIDTH - is similar to maximum effective length, but at right angles to it.

MAXIMUM LENGTH - is the length of a line connecting the two most remote extremities of a lake. It represents the true open-water length and does not cross any land other than islands.

MAXIMUM WIDTH - is the .length of a straight line connecting the most remote transverse extremities over the water at right angles to the maximum length axis.

MEAN DEPTH - is the volume of a lake divided by its surface area.

MEAN DEPTH-MAXIMUM DEPTH RATIO - is the mean depth divided by the maximum depth. It serves as an index figure which indicates in general the character of the approach of basin shape to conical form.

118 MEAK WIDTH - is the area of a lake divided by its maximum length.

MESOTROFHIC - generally refers to lakes which are intermittent between oligotrophic and eutrophic.

METALIMNION - is the layer of water in a lake between the epilimnion and the hypolimnion in which the temperature exhibits the greatest difference in a vertical direction.

MILLIGRAMS PER LITER (mg/1) - is used to express concentrations in water chemistry because it allows simpler calculations than the English system. The basis of the metric system is the unit weight and volume of water at standard conditions (20 C). At these conditions, one milliliter of water equals one cubic centimeter and weighs one gram. One milligram per liter is therefore, essentially equal to one part per million by weight or volume.

MILLIMETER (mm) - linear measurement equal to one thousandth of one meter (0.001 meter).

MONOMICTIC LAKE - is one with a single period of turnover during the year.

MORAINE - refers to a drift, deposited chiefly by direct glacial action, and having constructional topography independent of control by the surface on which the drift lies.

MUCK - is a dark-colored soil, commonly in wet places, which has a high percentage of decomposed or finely comminuted organic matter.

NON-POINT SOURCE POLLUTION - can be defined as any pollutant which reaches a water body by means other than through a pipe. Examples of non-point sources include leachate from dumps and agricultural runoff from dairy farms.

NUTRIENTS - are basically organic compounds made up of carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur. Small amounts are vital to the ecological balance of a water body. Larger amounts can lead to an upset of the balance by allowing one type of organism, such as algae, to proli- ferate. The most significant nutrients in water bodies are those of carbon, nitrogen, and phosphorus. Nutrients of carbon are measured indirectly in the BOD test; separate tests are run to measure nutrients of nitrogen and phosphorus.

OLIGOTRQPHIC - generally refers to lakes which are deficient in plant nutrients and have abundant dissolved oxygen.

ORTHOGRADE - is a stratification curve for temperature or a chemical sub- stance in a lake which as a straight, uniform course,

PEAT - is a dark-colored residual produced by the partial decomposition and disintegration of marsh plants.

119 PERCENT SATURATION - a comparison of the actual oxygen concentration to the theoretical maximum oxygen concentration that water can hold at a given temperature and pressure.

pH - is the measure of the hydrogen ion concentration of a solution on an inverse logarithmic scale ranging from 0 to 14. Values from 0 to 6.9 indicate acidic solutions, while values from 7.1 to 14 indicate alkaline solutions. A pH of 7.0 indicates a neutral solution. Natural streams usually show pH values between 6.5 to 7,5, although higher and lower values may be caused by natural conditions. Low pH values may result from the presence of acid mine drainage or metal-finishing waste. High pH values may result from detergents or photosynthetic activities of phytoplankton.

PHYLLITE - argillaceous rock intermediate in metamorphic grade between slate and schist.

PLUTONIC -of, or originating deep within the earth.

POINT SOURCE OF POLLUTION - refers to continuous discharge of pollutants through a pipe or similar conduit. Primarily included are sewage and industrial waste, whether treated or untreated.

SCHIST - medium or coarse grained metamorphic rock with subparallel orienta- tion of the micaceous minerals which dominate its composition.

SESTQN - refers to all the particulate matter suspended in the water.

SHORELINE - is the length of a lake's perimeter measured from a map with a rotometer (map measurer).

SILICA (SiOO - is necessary for diatom growth. The concentration of silica is often closely linked with the diatom population's growth. The limiting concentration is usually considered to be 0.5 mg/1.

SPECIFIC CONDUCTANCE - is a numerical expression of the ability of a water sample to carry an electric current.

THER.MOCLINE - is coincident with the metalimnion and relates to the lake zone with the greatest temperature change in a vertical direction.

VOLUME - is determined by computing the volume of each horizontal stratum as limited by the several submerged contours on the bathymetric (hydro- graphic) map and taking the sum of the volumes of all such strata.

120 APPENDIX F ALGAL ASSAY RESULTS

The following information was taken from a progress report to the Massa- chusetts Division of Water Pollution Control entitled Establishment of an Algal Assay Laboratory by S. Plotkin and N.M. Ram, Dept. of Civil Engineering, University of Massachusetts, Amherst, January 1982.

The report contained algal assay data from 18 sampling sites, one of which included Spy Pond.

One composite sample was taken from Spy Pond (Arlington, Massachusetts) during the spring turnover on April 3, 1981. The MSC for the site was equal to 1.11 mg dry wt of alga.e/1 indicating that the site had moderately high productivity (Figure C). Chemical analysis of the site indicated a N:P ratio of 66.4:1 reflecting extreme phosphorus limitation. Additions of 0.05 mg P/l and 1.00 mg N/l increased the algal yield to 22.71 mg dry wt/1 and 19.05 mg dry wt/1 respectively. An increased algal yield arising from both nitrogen and phosphorus additions is highly unusual. However, similar algal yields from these two additions may have indicated phosphorus and nitrogen co-limitation and an unusually low MSC for the control. The sample containing EDTA + 0.05 mg P/l had an MSC value of 37.28 mg dry wt/1 while the sample with 1.0 mg N/l + EDTA had an MSC value of 43.31 mg dry wt/1. These results were both much greater'than the 2.59 mg dry wt/1 algal yield exhibited by the control + EDTA sample. The algal growth data indicated apparent co-limitation for this site at this time. The data is somewhat atypical, however, since the observed algal yields, in most cases fell outside the usual 20 percent range of the predicted yield.

EDTA additions increased the algal yields substantially in all but the control (significant at the 95 percent level). The MSC in the control plus EDTA was equal to only 2.59 mg dry wt/1. It is likely there was heavy metal toxicity, an organic toxin, or trace metal limitation.

The biologically available phosphorus was equal to 0.44 mg P/l. This value was four times greater than the 0.11 mg P/l value obtained from chemical data indicating that the orthophosphorus analysis may have been in error. The bioavailable nitrogen concentration was 0.598 mg N/l or 82 percent of the 0.731 mg N/l value determined by chemical analysis.

121 r

FIGURE C PREDICTED AND ACTUAL YIELDS (mg/ dry wt/1) OF SELENASTRUM CAPRICORNUTUM GROWN IN SPY POND

80-- Predicted Yield Actual Yield T-80

60-- - -60

40 + - -40

20 - -20

« 0- U s C P N PN E PE NE PNE C P N PN E PE NE PNE

ApriM. 1981

C = Control E = + EDTA P = •+• phosphorus PE = + phosphorus + EDTA N = + nitrogen NE = + nitrogen + EDTA PN = -t- phosphorus + nitrogen PNE = + phosphorus + nitrogen + EDTA

I : 122 Table 14 summarizes Che data and results of the algal assays for Spy Pond,

TABLE 14 A SUMMARY OF THE DATA COLLECTED FROM SPY POND ON APRIL 3, 1981

_PARAMETER SPY POND

Nitrogen to phosphorus ratio* 66.4:1

Predicted limiting nutrient Phosphorus

Observed algal assay Co-limited Limiting nutrient result

Possible heavy metal toxicity Yes

* A ratio below 10:1 indicates likely nitrogen limitation. A ratio between 10:1 and 12:1 indicates likely co-limitation; however,co-limitation at values between 5:1 and 12:1 have been reported. A ratio greater than 12:1 indicates likely phosphorus limitation

123 APPENDIX C BOSTON WEATHER STATION, SUFFOLK CO. 42°22' LATITUDE-71°02' LONGITUDE DAILY PRECIPITATION*

DAY OF MONTH YEAR/MONTH TOTAL 12 3456789 10 11 12 13 14 1980 March 5.37 .04 .01 — .79 -- — .20 .01 .04 1.46 April 4.36 .05 — . 80 — — — T .111, 70 — T .10 May 2.30 .02 T — T . T .06 .62 T — — T .53 .08 June 3.05 .07 .22 .01 .09 — .13 .07 T .16 — July 2.20 .01 T — .17 T — .32 — — .07 — August 1.55 T .19 — — — — — — — .21 .03 .36 .37 September .82 T T T — T T T .15 — — T .08

October 4.14 T T . 75 . 65 — — — — — .30 T — November 3.01 . 26 — -- T . 10 26 T T T — December .97 T .05 — ~ — — .01 .13 .01 T .07 .01 1981 January .95 .22 T — — — .19 — — -08 — T T T

February 6.65 T .62 — — T — — .80 T -- .48 — March .62 T — — — .02 .22 — T T T T April 3.14 . 72 — -- .24 .42 — — .05 — .04 .34 * Data taken from: United States Department of Commerce, Environmental Data and Information Service. 1980-1981. Climatological Data (monthly record). National Climate Center, Asheville, North Carolina. Data reported in inches. T - Trace APPENDIX G (CONTINUED)

DAY OF MONTH YEAR/MONTH 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

1980 March .06 .58 — — .82 .71 T — .06 .01 — — .10 .48 — April .08 .04 — — — T ~ .01 .17 T — .06 .14 .41 .69 T May . 10 — T . 21 — — . 68 — — — — — — T June T .34 — — — .16 — — — — — — — T 1.49 .31 — July .01 .20 T — — T .01 .01 .04 — — — — — 1.35 .01 — ro August .08 T — — .15 .09 T .07 — — — — T — — — T Oi September .27 — — — — — — T .32 — October T T — .30 T — .01 — — — 1.84 T -- .29 — November .07 1.22.— — T -- — .22 .16 — — .72 — December T .45 .02 — T — — — .14 T — — — T — .08 — 1981 January ,02 .07 .22 — T — T — — .15 — February - — .07 — 08 .51 .21 T 02 1.21 2.15 .42 T .08 — March T - T .04 — .07 — .24 — — .03 April T T .01 — — 26 .59 .13 — — T .34 T