Question

Which of the following technologies is a best choice to address both runoff quantity and runoff quality problems?

Select the best answer

Select one:

a. Bioretention Filter

b. Vegetated filter strip

c. Underground detention basin

d. Catch basin insert

e. None of the listed technologies will address both water quality and quantity issues.

Answer 1

For adressing both runoff quality and quantity problems, Out of these, Underground Detention Basins will be the most effective technology.

An underground detention basin or retarding basin is excavated area for storing water and protecting from erosion in nearby rivers, streams, lakes or bays by storing water for a limited period .

Detention ponds which are designed to permanently retain some volume of water at all times are called retention basins. A detention basin manages water quantity with effectiveness in protecting water quality.

Detention basins are storm water best management practices which provide general flood protection and can also control extreme floods. The basins are typically built during the construction of new development projects. The ponds manages the excess urban runoff generated by newly constructed impervious surfaces such as roads, parking lots etc.

Extended detention dry basins can limit downstream erosion and control pollutants such as suspended solids. This type of basin differs from a retention basin, also called  "wet pond," and has a permanent pool of water, which is typically designed  to protect water quality.

While basic detention ponds are often designed to empty within 6 to 12 hours after a storm, extended detention (ED) dry basins improve on the basic detention design by lengthening the storage time, for example, to 24 or 48 hours. Longer storage times results in improved water quality because of removal of additional suspended solids