Winooski River Drainage Basin
photography: R. Farrell - Mount Philo, VT- Relationship between Elevation and Mean Annual Precipitation
2. Arithmic Average Precipitation
42. 14 inches (including Mansfield)
- 41.22 in (excluding Mansfield)
3. Influence of Elevation and Average Precipitation in the Winooski Drainage Basin
Average Yearly Precipitation in Basin: 44.29 inches/year
Due to the orographic effect, mountainous regions, at higher elevations get a greater amount of precipitation. This can be seen in the outlier data point in Mansfield with 70.04 in, 3950 ft, compared to the other data points with an average elevation of 802.57 ft and average precipitation of 41.22 in.
Sites 3, 12, 14, 15, and ,28 are located in the Winooski Basin. The average precipitation for these five sites is 44.29 in/year. The average is muhch higher considering, Mansfield is site 15; without Mansfield the average would be 37.86 in/year.
(I will continue with the result including Mansfield.)4. Total Volume of Precipitation
Total Volume of Precipitation in Basin: 3.04 cubic km/year
According to the USGS, the Winooski River Drainage Area is 1044 square miles. The average precipitation rate is 44.29 in/yr. The total volume of precipitation for the Winooski River Drainage Basin is 3.04 cubic km/ year
5. Total Run-off Volume
Total Run-off Volume in Basin: 1.6229 cubic km/year
The Mean Annual Discharge for the Winooski Basin is 1817.36 cfs (cubic ft/sec). Using this data, the total run-off volume for the basin is 1.6229 cubic kilometers per year.
5. Mean Annual Discharge versus Average Yearly Precipitation
Mean Annual Discharge in Basin: 1817.36 cubic ft/sec -> Total Run-off Volume: 1.6229 cubic km/year
Average Yearly Precipitation in Basin: 44.29 inches/year -> Total Volume of Precipitation: 3.04 cubic km/year
With these values, the average percentage of the rainfall that runs off would be 53.4%. Around half of the precipitation that falls into the Winooski Drainage Basin gets discharged as run-off into Lake Champlain. Presumably, most of the 46.6% of precipitation that does not get discharged is emitted back into the atmosphere through evapotranspiration, by absorption and transpiration through vegetation or evaporation out of soils and surfaces. Humans play a role in the removal of run-off, however, whether through wastewater treatment facilities, sewers, or other processes, that water is eventually discharged into run-off again.
6. Mean Annual Dissolved Load and Mean Annual Suspended Load
Mean Annual Dissolved Load: 49.067 tons/sq km*year
Mean Annual Suspended Load: 48.617 tons/sq km*year
Dissolved Load Calculations avg. TDS * discharge vol / area
Comparisons
The dissolved loads and suspended loads had similar averages of 49.1 Mg/sq km•yr and 48.6 Mg/sq km•yr, respectively. Since there is minimal data, it is possible that this similarity is a mere coincidence. There are very little data points for suspended solids, so there is no clear trend, but there is a possible positive correlation with discharge. Total dissolved solids appear to decrease with discharge, while there appears to be a positive correlation between conductivity and total dissolved solids. Cuban waters show a similar correlation between TDS and conductance. The Winooski Basin waters are more acidic than that of the primarily neutral or slightly alkaline Cuban waters. The total dissolved solids and conductivity in Cuban waters is higher. The sediment loads are largely influenced by chemical interactions between the rock and water, commonly the dissolution of readily weatherable evaporites.
