Question 47

The minimum slope for a gutter of a 6-inch storm drainage system is 1/8 inch per foot.

A minimum slope of 1/8 inch per foot is necessary for effective drainage in a 6-inch storm drainage system to ensure that water flows properly and does not pool.

A) 1/16 inch per foot

This option is incorrect because a slope of 1/16 inch per foot is insufficient for a 6-inch storm drainage system. It does not provide adequate gravitational flow, potentially leading to standing water and drainage issues.

B) 1/8 inch per foot

This option is correct as it meets the minimum requirement for the slope of a gutter in a 6-inch storm drainage system. A slope of 1/8 inch per foot ensures that water is directed efficiently toward the drainage outlet, reducing the likelihood of blockage and overflow.

C) 1/4 inch per foot

While a slope of 1/4 inch per foot would allow for good drainage, it is greater than the minimum requirement. This option is not necessary and could lead to unnecessary complications in the design and installation of the drainage system.

D) 1/2 inch per foot

This option is also incorrect because a slope of 1/2 inch per foot is excessive for a 6-inch storm drainage system. Such a steep slope could result in increased erosion and may complicate the overall drainage design without providing additional benefits.

Conclusion

The correct answer, 1/8 inch per foot, is the minimum slope required for effective drainage in a 6-inch storm drainage system. Other options either provide insufficient drainage capabilities or exceed what is necessary, which could complicate installation and operation without added benefit.