Of course, the main influence on streamflow is precipitation runoff in the watershed. Rainfall causes rivers to rise, and a river can even rise if it only rains very far up in the watershed-remember that water that falls in a watershed will eventually drain by the outflow point.
One US gallon of water weighs 133.526464 ounces. The calculations for that answer are below: 1 gallon = 8.345404 pounds 1 pound = 16 ounces 8.345404 X 16 = 133.526464.
One cubic foot of water contains 7.48 gallons of water, weighing in at 62.31 pounds. The Handbook of Chemistry and Physics specifies the weight of 1 US gallon of water in air at 68 degrees F to be 8.32487 pounds or 3776.103 grams. To say the temperature of the water affects the weight is somewhat misleading.