By Mary Spicer
Over the years, the concept now known as stormwater management has evolved. From the days of running excess water aboveground in ditches and later taking it underground in stormwater pipes, minimizing the negative impact of water falling from the sky has come to include a wide range of features including best management practices and low impact development designed to control not only the path of stormwater but also its volume and quality.
The City of Meadville — together with countless municipalities across the country — now faces the reality that the basic structure upon which modern programs must be built has been in place since all a municipality had to do was move stormwater somewhere else.
Even if ripping the whole system out wouldn’t be a logistical nightmare, “the replacement value of the city’s existing stormwater management and related infrastructure assets would be approximately $500,000 to $750,000,” the city’s stormwater consultants, Jean Haggerty and Brian Merritt of AMEC Environment & Infrastructure Inc., reported to the city’s Stormwater Stakeholder Advisory Committee during a recent meeting.
Combining that estimate with best practices recommending that 1 percent of existing infrastructure be replaced on an annual basis, the city should — in theory — be investing between $5 million and $7.5 million per year in its stormwater system.
Based on costs Haggerty and Merritt were able to document through the examination of budget information and activity reports, however, less than $120,000 is being spent on an annual basis on a combination of infrastructure assessment, infrastructure rehabilitation and capital improvements to the system. In 2010, for example, roughly 0.3 percent of the city’s storm sewer system was replaced. Catch basins and inlets are replaced only on an as-needed basis, while major repairs are required to keep stormwater-related equipment — including the crucial streetsweeper — on the streets.
In addition, the city is currently cleaning only about half the existing stormwater inlets and 2 percent of the existing stormwater pipes on an annual basis.
Before major infrastructure decisions can be made, however, “an existing conditions assessment of the entire stormwater system is needed to further investigate and document the current condition of the city’s stormwater structure,” the consultants reported to the committee.
“This assessment will help to identify areas which may require short or long-term repairs and replacement,” the consultants continued. “This assessment will also help to further extend the service life of existing infrastructure via targeted maintenance and inform the creation of a prioritized Capital Improvement Plan.
Although the city’s stormwater system has yet to be thoroughly examined, Meadville Area Sewer Authority has already made a substantial investment in inspecting its sanitary system. As a result, “MASA identified 40 cross connections between the storm sewer and the sanitary sewer system,” Haggerty and Merritt reported. “Flow from stormwater runoff can overwhelm the sanitary sewer system and cause backflow issues. The city will need to implement a plan to eliminate these cross connections.”
According to the consultants, stepping up the pace of storm sewer reconstruction and inlet replacement beyond the existing level would also have both structural and fiscal benefits, reducing the number of emergency infrastructure repairs, minimizing liability created by emergency situations and helping to control costs by coordinating purchases in advance.
Into the office
An update in the way the city’s stormwater system is administered is also required.
The official map of the city’s storm drainage system, for example, appears to have been beautifully maintained — but it’s on paper and bears the date 1942.
According to Haggerty and Merritt, that simply won’t do. “To meet permit requirements and assist in the improved system management, an electronic GIS (geographic information system) map and database of all city stormwater infrastructure is needed,” they reported to the committee.
While a long list of stormwater-related administrative duties has been distributed throughout the ranks of city staffers, much more needs to be done to improve the existing system and prepare for changes that will be required with the revised and expanded MS4 permit.
A preliminary list prepared by the consultants of current limitations and gaps in the city’s current stormwater review, inspection, administration and enforcement functions included:
- Administration and budget coordination for the city’s stormwater management program should be enhanced to better support and manage program and infrastructure needs.
- Oversight of land development and approval process should be improved.
- Site inspections of construction projects should be increased.
- A comprehensive database and inventory of all stormwater-related best management practices, including both public and private BMPs, should be developed.
- A private BMP post-construction inspection program should be initiated.
Mary Spicer can be reached at 724-6370 or by e-mail at firstname.lastname@example.org.