Question

A half inch of sediment composed of 22% sand, 41% silt, and 37% clay is deposited each year in a reservoir. Estimate the total thickness of the deposit after 25 years if there is normally a moderate reservoir drawdown. You will need to calculate a value of for pounds of material deposited each year nar cruara font (ncf) tn aid vour conversion from bcf to in. Create columns for your analysis as follows:

Answer 1

To estimate the total thickness of the deposit after 25 years, we can start by calculating the annual deposit in pounds of material. Given that half an inch of sediment is deposited each year, we can convert this to pounds using the provided percentages of sand, silt, and clay.

Let's assume the density of the sediment is 100 pounds per cubic foot.

First, we calculate the volume of sediment deposited each year (V) in cubic feet:

V = (0.5 inches / 12) * 1 acre-foot

Next, we calculate the weight of each component of sediment (W) based on their percentages:

Weight of sand = V * 22%
Weight of silt = V * 41%
Weight of clay = V * 37%

Finally, we add up the weights of sand, silt, and clay to get the total weight of sediment deposited each year (Total Weight):

Total Weight = Weight of sand + Weight of silt + Weight of clay

To estimate the total thickness of the deposit after 25 years, we multiply the Total Weight by the number of years (25) and divide by the cross-sectional area of the reservoir to get the thickness in inches.

Here's a table showing the analysis:

| Component | Percentage | Weight Calculation |
|----------------------|------------|------------------------|
| Sand | 22% | V * 0.22 |
| Silt | 41% | V * 0.41 |
| Clay | 37% | V * 0.37 |
| Total Weight | | Sum of Sand, Silt, Clay|
| Thickness after 25 years | | (Total Weight * 25) / Cross-sectional Area |

Please note that the cross-sectional area of the reservoir is required to calculate the final thickness.