Problem 1:
An in-ground swimming pool may have a leak. The 30-ft by 10-ft by 5-ft (depth) pool is filled on June 1. On June 13, a hose, flowing at a rate of 10 gallons per minute, is used to add water to the pool. The hose is turned off after 1 hour. Four inches of rain fell during the month.
Evaporation from a nearby lake was 8 in. during June. It is estimated that 25 percent more will evaporate from the pool than the lake. On July 1, the pool is 5 inches below the top. Does the pool have a leak? If so, what is the rate of leakage in gallons per day?
Problem 2: A dry detention basin is to be designed for a 70 ha residential development. The runoff coefficient for the area is 0.3 and the average rainfall during the year is 4 cm. What is the necessary volume for the basin?
Problem 3:
What is the peak discharge for an area with the following characteristics? The rainfall intensity is 120 mm/hour.
Land use Area, m2
Forest 10,000
Single family residential 9,000
Parking lots 5,000