Lake Issues

Water Quality

Impacts of the 7/11/2019 Mascoma River upstream wash-out

Data gathered before (6/27/19), right after (7/16/19) and a year
later (6/16/20) seperated in columns below by forward slash /

Location
Mascoma
Lake
Color Turbidity Total Phosphorus
70 / 170 / 50 0.73 / 11.6 / 0.74 12.4 / 24.0 / 10.0
2m deep – – – 0.64 / 3.4 / 0.8 8.6 / 18.0 / 7.0
9m deep – – – 0.73 / 3.5 / 1.7 12.4 / 14.0 / 12.0
Mascoma
River
Inlet
– – – 1.98 / 3.5 / 2.73 12.6 / 18.0 / 15.00
Secchi Disk = 2.75m = 9ft / 1.0m =3ft / 3.5m = 11.5ft

 

Water Quality Terms:

COLOR (Water Clarity): Clear 0-25 / Light Tea-Color 25-40 / Tea Color 40-75

Turbidity is a measure of the cloudiness or lack of clarity of water, caused by the scattering or absorption of light by sediment, algae, or other particulates suspended in water. Chronic and high levels of turbidity can impair designated uses such as aquatic life and primary recreation (swimming). Turbidity is measured in Nephelometric Turbidity Units (NTU).

Phosphorus – is an essential element for plant life, but when there is too much of it in water, it can speed up eutrophication (a reduction in dissolved oxygen in water bodies caused by an increase of mineral and organic nutrients) of rivers and lakes. Soil erosion is a major contributor of phosphorus to streams. Bank erosion occurring during floods can transport a lot of phosphorous from the river banks and adjacent land into a stream, lake, or other water body.

Secchi disk  an 8-inch diameter disk with alternating black and white quadrants that is lowered into the water column until it can no longer be seen from the surface. The point at which the disk disappears is a function of the lake turbidity.

Volunteer Lake Assessment Program:

VLAP 2013 report

VLAP 2017 report

VLAP 2019 report

Q2  2018 Mascoma Lake Water Quality Report*
By Jim Martel 

Parameter 6/12/2018 6/20/2017 6/21/2016 NH Median Long Term
Trend
Secchi Disk, m 5.0 3.1 2.9 3.2 Slowly
Improving
Chlorophyll-a, µg/L 1.96 0.99 4.56 4.58 Stable
Phosphorus, µg/L
Epilimnion (upper)
Hypolimnion (lower)
9.0
18.0
6.0
8.0
7.0
9.0
12
14
Stable
Turbidity, NTU
Epilimnion (upper)
Hypolimnion (lower)
.79
4.01
0.59
1.05
1.12
.99
N/A No sig.
Change
PH
Epilimnion (upper)
Hypolimnion (lower)
7.24
6.41
7.07
6.42
7.35
6.54
6.6 No sig.
Change
Acid Neutralizing
Capacity, mg/L

Epilimnion (upper)
4.4 10.2 9.7 4.9 No sig.
Change
Conductivity,
µmhos/cm

Epilimnion (upper)
Hypolimnion (lower)
72.1
67.7
67.4
65.0
72.0
76.5
40.0 Slowly
Increasing

* Samples taken from Station 1 Deep Spot.

Some Things You Can Do To Improve Lake Water Quality
•Use cleaning products containing no phosphates.
•Use only zero phosphate fertilizer on your lawn.
•Reduce and/or redirect storm water running off your property. For more info on Stormwater Management click HERE
•Leave the shoreline and nearshore area in its natural state. Conversely, restore altered shorelines to a more natural state.
•Don’t feed the waterfowl.
•Don’t dump sand in the lake.

Mascoma Lake Reports PDF

To get a report on water quality inspections on ML beaches click HERE