PHRC Report #7: Analysis of the Policies and Procedures of Storm Water Management

Date: March 1991

Author(s): G. Aron, C. McIntyre, J. H. Willenbrock

BACKGROUND:

The concept of storm water management for environmental protection was developed due to topographical and soil cover changes brought about by increased urbanization. Inadequate management of storm water runoff resulting from development increases flood flow and velocities, contributes to erosion and sedimentation, overtaxes the carrying capacity of streams and storm sewers, reduces groundwater recharge, and can be a threat to public health and safety.

In response to these issues, the General Assembly of the Commonwealth of Pennsylvania passed the Storm Water Management Act in 1978. The effects of this legislation have had a tremendous impact on virtually every community in the Commonwealth, resulting in the creation and enactment of storm water management ordinances. However, a need exists to periodically review and upgrade current storm water management policies and practices to determine possible shortcomings in light of past experience of system performance and recent advancements in design methodology and technology.

SUMMARY OF RESULTS:
Comprehensive storm water management incorporating both quantity and quality aspects should occur at the watershed level.

Too much emphasis is placed on the control of runoff from extremely rare events. More attention should be addressed to the less-frequent storm events.

Where applicable, alternative methods of diffusing and recharging post-development runoff should be employed.

On-site inspection and as-built drawings of storm water management systems should be standard practice.

Upon project completion, all components of the storm water management system should be dedicated to the municipality or storm water management authority. Various funding mechanisms are available for the continued maintenance and repair of the system.

WHAT IT MEANS TO YOU:

Some of the results of this report have been used to upgrade current storm water management regulations, thus aiding in the design and approval process for residential development.

WHAT'S NEXT?

Phase II of this study will explore alternative and innovative measures of controlling and detaining runoff. Various methods for estimating storm runoff will be compared. Recommendations focusing on cost and performance will be formulated.