Arizona State University COLLEGE OF LIBERAL ARTS AND SCIENCES
SCHOOL OF EARTH AND SPACE EXPLORATION

 

Solutions

StreamFlowKM#3: Snow Melt and Stream Flow for the Animas River(Level 2)
Mathematical Content: Area, Volume, Unit Conversion, linear equations.

SOLUTIONS: KM # 3  Animas River and Snow

 

 

Question 1:  Assume that there is no snow melt during the months when average temperature is freezing or below; during this period, snow accumulates. From the data above, find which months snow isaccumulating. 

January, February March, November, December

Question 2: From the data above, compute the total water (in inches) from snow during the months of freezing temperatures.


9.24 inches (Depth of water from snow)

Question 3:  Convert your answer to #2 to feet (1 ft = 12 inches).


img (Depth of water from snow)

Question 4: The area of the drainage basin, or watershed, for the Animas from source to Durango is roughly 700 square miles.* What is the area of the watershed in square feet? (Using scientific notation, round to 2 decimal places.)

e 

Question 5: Find the total volume (in cubic feet—use your answers to #3 and 4) of water from snow that falls on the watershed during the freezing months. (Volume = Area of Base x Height; Using scientific notation, round to 2 decimal places.)

e

Question 6: Assume that it takes 4 months for all the snow to melt after temperatures go above freezing. From Table 2, convert the rainfall data to feet for each of the four months of snow melt. (Round to 2 decimal places.)

Apr      e (Depths of rainfall)

 

May     e

 

Jun       e

 

Jul        e           

Question 7: Use your four answers to #6 and your answer to #4 to compute the volume of rain over the watershed for each of the four months of snow melt. Your four answers will be in cubic feet. (Round to 2 decimal places.)
Apr      e 
May     e
Jun       e
Jul        e

Question 8: Table 3 below gives the percentage of total snow that melts during each of the four months. Refer to your answer to #5, and find the volume of snow that melts in each of the four months. Your four answers will be in cubic feet. (Round to 2 decimal places.)

Month

April

May

June

July

% of

2

38

56

4

e      

e

e

e

e

Question 9: Next, find the total volume of water, rain from #7 + snow melt from #8, over the watershed for each of the four months. (Round to 2 decimal places.)

Apr      e 
May     e
Jun       e
Jul        e

Question 10: Assume that only 74% of all water actually reaches the river bed (the rest is evaporated or drawn off for agricultural or domestic use). Find the streamflow for the Animas River for each of the four months of snow melt. (Round to 2 decimal places.)

Apr      e  (Volume of water to river)
May     e
Jun       e
Jul        e

Question 11: .Convert your answers to #10 to cubic feet per second. (Round to nearest cubic foot.)
(1 day = 24 hours, 1 hour = 60 minutes, and 1 minute = 60 seconds)

Apr      e  (Volume of water to river)

May     e

Jun       e

Jul        e
           

Note. Actual averages are: 817; 2287; 3043; 1295.