WEBSTER LAKE

Routine sampling at the designated station in winter

Photo.
Photo: Dufresne-Hnery Inc.  
 

A. LOCATION

New Hampshire, USA. 43:8N, 71:1W; 122.2 m above sea level.

B. DESCRIPTION

The Webster Lake Watershed spans two municipals in the south-central portion of the Lakes Region of New Hampshire. The total watershed consists of approximately 11,432 acres, contains two major lakes, numerous small ponds and an extensive system of tributaries. The majority of the watershed - 8,363 acres (73.2% of the total basin) - is in the eastern portion of the town of Andover, New Hampshire. The watershed can be considered typical of the Lakes Region in New Hampshire. Vast forested areas and agricultural corn fields are broken only by scattered single-family dwellings which parallel existing road networks, with dwelling concentrations around typical "village" layouts.
The watershed is dominated by Highland Lake in Andover, and Webster Lake in Franklin. The two lakes are connected by Sucker Brook, the largest of the many tributaries within the watershed. Webster Lake (612 acres) is the larger of the two lakes, being 1.6 miles in length by 1.0 mile wide.
Presently, approximately 90% of the 4.3 miles of shoreline is developed. The lake is subject to extensive recreational use. The lake, at an elevation of 401 feet above sea level, has an average depth of 19 feet, a maximum depth of 45 feet, and has two public beaches and one public launch.
A priority list developed by the Department of Environmental Services' Biology Bureau has rated Webster Lake as high for both restoration and preservation. The lake is located within 25 miles of the Capitol City of Concord and is also within 25 miles of the City of Laconia.
An earlier Water Quality Management Investigation of Wabster Lake in 1980, revealed that Sucker Brook, the main tributary to Webster Lake accounted for approximately 67% of the total water input to the lake, drains about 80% of the entire watershed area and is responsible for approximately 63% of the phosphorus loading to the lake during a normalized year.
The trophic classification of Webster Lake was determined to be mesotrophic, based on data collected and a comparison with the trophic classification System for New Hampshire Lakes and Ponds. These guidelines were formulated to classify New Hampshire lakes and ponds for the federal "Clean Lakes" program. A total of six points were awarded to Webster Lake based on this rating system. This ranked Webster Lake as number 24 on the priority list for restoration.
An on-site inspection of the Webster Lake watershed revealed several agricultural areas which were in close proximity to Sucker Brook or had feeder streams flowing into Sucker Brook as possible sources of nutrient loads.
Many of the recommendations suggested in the Water Quality Management Investigation of Webster Lake deal with stricter ordinances around the lake and best management practices. The report calls for proper agricultural management implementation at individual farms sites (1).

C. PHYSICAL DIMENSIONS (1)

     
    Surface area [km2] 3
    Volume [km3] 0.1405
    Maximum depth [m] 13.7
    Mean depth [m] 5.7
    Water level Regulated
    Normal range of annual water
    level fluctuation [m] 6.0
    Length of shoreline [km] 6.9
    Residence time [yr] 0.6
    Catchment area [km2] 43
     
 

D. PHYSIOGRAPHIC FEATURES

D1 GEOGRAPHICAL
Bathymetric map: Fig. NAM-39-01.
Names of main islands: None.
Number of outflowing rivers and channels (name): 1 (Chance Pond Brook).
D2 CLIMATIC
Climatic data (1, 2)
Mean temp. [deg C]*1
     
    Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ann.
    -9.3 -4.7 0.0 6.9 13.8 17.3 21.1 19.3 14.9 7.7 3.5 -4.1 7.2
     
Precipitation [mm]*2
     
    Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ann.
    50 45 54 67 76 89 98 86 84 75 67 54 845
     
*1 Concord, September 1974-August 1982.
*2 Burlington (VE), 1931-1960.

    Fig. NAM-39-01
    Bathymetric map (Q).
 

Water temperature [deg C]
1988
[m]

     
    Depth Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
    S* - - - 8.8 - - 24.1 - - 13.7 6.5 -
    1 - - - 7.6 - - 24.0 - - 13.7 6.5 -
    2 - - - 7.4 - - 23.9 - - 13.7 6.5 -
    3 - - - 7.6 - - 23.8 - - 13.7 6.5 -
    4 - - - 7.5 - - 23.6 - - 13.7 6.5 -
    5 - - - 7.6 - - 21.6 - - 13.7 6.5 -
    6 - - - 7.5 - - 19.2 - - 13.7 6.5 -
    7 - - - 7.5 - - 17.4 - - 13.6 6.5 -
    8 - - - 7.6 - - 16.3 - - 13.6 6.5 -
    9 - - - 7.7 - - 14.9 - - 13.6 6.5 -
    10 - - - 7.9 - - 14.2 - - 13.6 6.5 -
    11 - - - 7.7 - - 13.5 - - 13.5 6.5 -
    12 3.0 - - - - - 13.2 - - 13.5 - -
     
* Surface.
Freezing period: November-March (Q).
Mixing type: Dimictic (Q).
Notes on water mixing and thermocline formation
Stratifies in the summer and in the winter.

E. LAKE WATER QUALITY

E1 TRANSPARENCY [m](1)
November 1987-October 1988
[m]
     
    Depth  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
    - - - 3.4 4.2 4.1 4.7 4.5 4.5 3.9 2.2 -
     
E2 pH (1)
Station 1, September 1979-August 1980
[m]
     
    Depth Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
    0 6.2 - - 6.4 7.0 6.4 6.8 6.8 6.5 - 6.2 -
    3 6.4 6.0 - 6.3 7.1 6.7 6.8 6.7 6.3 - 6.2 -
    6 6.2 5.9 - 6.2 6.7 6.8 6.8 6.7 6.4 - 6.3 -
    9 - - - 6.1 6.5 6.4 6.1 6.4 6.2 - 6.3 -
    12 - - - - - 6.1 6.4 6.5 - - - -
     
E4 DO: Fig. NAM-39-02.

    Fig. NAM-39-02
    Vertical distribution of DO [mg l-1] and water temperature [deg C].
 

E6 CHLOROPHYLL CONCENTRATION [micro g l-1](1)
November 1987-October 1988
[m]

     
    Depth Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
    - - - - 6.16 2.97 6.13 6.53 2.47 4.98 7.09 6.88 -
     
E7 NITROGEN CONCENTRATION (1)
Total-N [mg l-1]
Station 1, September 1974-August 1980
[m]
     
    Depth Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
    0 .20 - - .25 <.10 .22 .26 .74 .16 - .39 -
    3 1.00 .27 - .18 .15 .20 .24 .64 .15 - .19 -
    6 1.95 .24 - .21 .13 <.10 .21 .62 .13 - .13 -
    9 - - - .23 <.10 .19 .24 .26 .14 - .16 -
    12 - - - - - <.10 .28 .37 - - - -
     
Total Kjeldahl-N [mg l-1]
Station 1, September 1979-August 1980
[m]
     
    Depth Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
    0 .20 - - .25 <.10 .37 .23 .24 .16 - .39 -
    3 1.00 .27 - .18 .15 .39 .27 .22 .15 - .19 -
    6 1.95 .24 - .21 .13 .44 .29 .24 .13 - .13 -
    9 - - - .23 <.10 .42 .26 .23 .14 - .16 -
    12 - - - - - - .49 - - - - -
     
E8 PHOSPHORUS CONCENTRATION (1) Total-P [mg l-1]
Station 1, September 1979-August 1980
[m]
     
    Depth Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
    0 .010 - - .014 .010 .012 .021 .006 .010 - .009 -
    3 .008 .008 - .014 .011 .015 .020 .009 .011 - .009 -
    6 .008 .008 - .013 .012 .005 .008 .014 .010 - .011 -
    9 - - - .012 .016 .003 .022 .021 .013 - .009 -
    12 - - - - - .142 .057 .068 - - - -
     
 

F. BIOLOGICAL FEATURES

F1 FLORA (3) 1979
Emerged macrophytes: Sparganium, Scirpus, Pontederia, Typha.
Floating macrophytes: Nymphaea, Nuphar.
Submerged macrophytes: Potamogeton, Vallisneria americana, Nitella.
Phytoplankton
Tabellaria, Melosira, Mallomonas, Asterionella, Dinobryon, Ceratium, Uroglenopsis, Anabaena, Fragilaria, Staurastrum, Sphaerocystis, Rhizosolenia, Peridinium, Mougeotia.

    Fig. NAM-39-03
    Distribution of aquatic plants, July 1979 (3).
 

F2 FAUNA
Zooplankton (3)
Kellicottia, Keratella, Polyarthra, Bosmina, Diaptomus, Cyclops, Vorticella, Codonella, Arcella.
Benthos: Cironomids, tubificid worms, planarians and caddis worms (3).
Fish (4, 5)
Catostomus commersoni, Rhinichthys atratulus, Perca flavescens, Morone americana, Micropterus dolomieui, Notemigonus crysoleucas, smelts, sunfish, Ictalurus nebulosus, Esox.

G. SOCIO-ECONOMIC CONDITIONS

G1 LAND USE IN THE CATCHMENT AREA (1)
1981
     
    Area [km2] [%]
    Natural landscape
    Forest 3,601.8 83.7
    Agricultural land
    Inactive 195.1 4.5
    Active 185.8 4.3
    Residential area 127.9 3.0
    Lake front
    Low density 50.7 1.2
    Med. density 29.1 0.7
    High density 19.0 0.4
    Industry 2.8 0.4
    Public 60.3 1.4
    Conservation 29.5 0.7
    Total 4,302 100
     
G2 INDUSTRIES IN THE CATCHMENT AREA IN THE LAKE (1)
Main agricultural products: Grapes, dairy products, beef.
Number of domestic animals in the catchment area: Cattle 60, horses 10.
G3 POPULATION IN THE CATCHMENT AREA (1)
     
    Population Major cities
    Population density [km-2] (population)
    Rural 792*
    825*2 None
    Total 1,622 18.4 (37.7)
    *1 Year around. *2 Seasonal.
 

H. LAKE UTILIZATION

H1 LAKE UTILIZATION
Sources of water, sightseeing and tourism and recreation (swimming, sport- fishing).

I. DETERIORATION OF LAKE ENVIRONMENTS AND HAZARDS

I1 ENHANCED SILTATION (Q)
Extent of damage: Not serious.
I2 TOXIC CONTAMINATION
Present status: None.
Environmental quality standards for contamination in lake water
     
    Classification
    Quality A B C
    DO [ppm] >6 >6 >5-6
    ( >75% of saturation)
    Sludge deposit None No reasonable kinds or quantity
    Oil & Greese None No reasonable kinds or quantity
    Gross radioactivity A, B, C <1000 picocuries 1-1
    Strontium-90 A, B, C <10 picocuries 1-1
    Phenol [ppm] <0.001 <0.001 <0.002
     
I3 EUTROPHICATION
Nitrogen and phosphorus loadings to the lake [kg yr-1](1)
     
    Sources T-P
    14 tributaries 45,870
    Natural 6,812
    Dry fallout (30% of precipitation) 2,043
    Sewage loading 7,131
    Total 61,956
     
Supplementary notes (Q)
Eutrophication is mainly caused by nutrient enrichment from upstream dairy farms.

J. WASTEWATER TREATMENTS (Q)

J1 GENERATION OF POLLUTANTS IN THE CATCHMENT AREA
    d) Measurable pollution with limited wastewater treatment.
J3 SANITARY FACILITIES AND SEWERAGE
Percentage of rural population with adequate sanitary facilities (on-site
treatment systems): Common but exact figure not available.
Municipal wastewater treatment systems: None.

L. DEVELOPMENT PLANS (1)

Watershed population projections up to the year 2000 show an expected increase of 6.1%. Part of this growth may include conversion of secondary homes to primary, and with this accompanying impact upon the septic systems, and therefore Webster Lake. Future development is expected to be primarily of a moderate residential nature.

M. LEGISLATIVE AND INSTITUTIONAL MEASURES FOR UPGRADING LAKE ENVIRONMENTS

M1 NATIONAL AND LOCAL LAWS CONCERNED
Names of the laws (the year of legislation)
  1. Water Supply & Pollution Control (1984) Responsible authorities
  2. Federal
  3. State
  4. Local Main items of control
  5. Algae and other aquatic nuisances
  6. Exotic weeds
  7. Illegal dumping and other violations
M2 INSTITUTIONAL MEASURES
  1. New Hampshire Department of Environmental Services, Water Supply and Pollution Control Division, Biology Bureau
 

N. SOURCES OF DATA

  1. Questionnaire prepared by the editors with the support of Dufresne-Henry Inc., based on the following sources.
  2. Dufresne-Henry Inc. (1981) Water Quality Management Investigation, Webster Lake, Franklin, New Hampshire.
  3. Court, A. (1974) The Climate of the Conterminous United States. "World Survey of Climatology, Volume 11, Climates of North America" (ed. Bryson, R. A. & Hare, F. K.), p. 336. Elsevier Scientific Publishing Company, Amsterdam-London-New York.
  4. Department of Environmental Services, New Hampshire Water Supply and Pollution Control Division (1987) Webster Lake Diagnostic/Feasibility Study Grant Application.
  5. Newell, A. E. (1977) Biological Survey of the Lake and Ponds in Sullivan Merrimack, Belknap and Stratford Counties. State of New Hampshire Fish and Game Survey Report # 8b.
  6. Scarola, J. F. (1973) Freshwater Fishes of New Hampshire. New Hampshire Fish and Game Department, Division of Inland and Marine Fisheries.