256,505 views
6 votes
6 votes
Calculate the change in storm water runoff in cubic feet per second caused by building a house on the Noblesville, IN lot assuming the following conditions. Use these tables and type only the number in the field below. (43,560 ft2/acre)

Ø Pre-development

o a 100 year, 1 hour design storm. Rainfall intensity – 3.05 in/hr

o Assume that 90% of the 0.5 acre lot is concrete pavement and 10% is grass lawn (flat, well drained, sandy soil)

o Use average values for pre-development coefficients

Ø Post development

o Plans include a two story house with a 1500 sq. ft. foot print and about 500 sq. ft. of concrete driveway, deck, and sidewalk.

o The remainder of the lot will be planted with grass lawn (flat, well drained, sandy soil).

o Use worst case coefficients for impervious developed surfaces and average values for other surfaces.

User Fin
by
2.9k points

1 Answer

15 votes
15 votes

Use worst case coefficients for impervious developed surfaces and average values for other surfaces.

User Farouk Alhassan
by
3.0k points