Geohydrology

STATE MEAN PRECIPITATION

1306.70"/31 total values = 45.05"

WINOOSKI RIVER BASIN MEAN ANNUAL PRECIPITATION

Recorded values in the Winooski River Basin: 3, 12, 14, 15, 28

Corresponding mean precipitation: 34.47, 40.94, 34.38, 70.04, 41.64

MEAN PRECIP = 221.47"/5 values = 44.29"

WINOOSKI RIVER BASIN TOTAL ANNUAL PRECIPITATION

MEAN PRECIP = 44.29"/yr * (2.54e-5 km/1") = 0.00125 km/yr

TOTAL AREA: 1,044 mi^2 * (2.589975 km^2/1mi^2) = 2703.93 km^2

TOTAL ANNUAL PRECIP = 2703.93 km^2 * 0.00125 km/yr = 3.38 km^3 per year

WINOOSKI RIVER BASIN TOTAL RUN OFF

MEAN ANNUAL DISCHARGE =

1818 cfs*(60s/m) * (60m/hr) * (24hr/day) * (365 day/yr) = 57332448000 ft^3/yr -->

57332448000 ft^3/yr * (1 km^3/3.531e+10 ft^3) = 1.623 km^3/yr

DISCHARGE/PRECIPITATION = 1.623 km^3/yr / 3.38 km^3/yr = 0.48 = 48% of rainwater runs off

MEAN ANNUAL DISSOLVED & SUSPENDED LOAD

TDS = 1.623 km^3/yr * 81.75 mg/L* (Mg/1e+9 mg) * 1/2745.37km^3 * (10^12L/1 km^3) = 48.24 Mg/km^2/yr

SUSPENDED = 1.623 km^3/yr * 81 mg/L* (Mg/1e+9 mg) * 1/2745.37km^3 * (10^12L/1 km^3) = 47.8 Mg/km^2/yr

The Winooski River basin's annual rainfall is far greater than discharge in that same area. This is likely due to a number of factors. In great part, rainwater does not contribute to discharge as forested areas will absorb & then release rainwater through evapotranspiration. Some water also infiltrates into groundwater reservoirs, while the rest evaporates directly into the atmosphere.

As calculated with the few data points available, the mean annual dissolved load is slightly higher than suspended load in the Winooski River Basin, at values of 48.24 Mg/(km²*yr) and 47.8 Mg/(km²*yr), respectively. These values are low in comparison to mass flux out in Cuban basins as found in Bierman et. al's 2020 study. This could be due to differences in bedrock—while carbonate Cuban bedrock is highly soluble, which increases transportable sediment in river basins, Vermont bedrock is less prone to weathering, and thus does not contribute to mass flux to the same degree.

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