New stormwater management requirements proposed for Mt. Lebanon

Home improvements such as additions are intended to increase property values, but they also have an unintended consequence.
“No matter what you’re doing, you have to consider the additional stormwater,” Mt. Lebanon municipal engineer Dan Deiseroth said. “It’s the proper thing to do. The storms that we have are much more frequent and affecting other people.”
During the Mt. Lebanon Commission’s Aug. 14 discussion session, Deiseroth presented recommendations with regard to amending the municipality’s stormwater management ordinance.
Chief among the proposed changes would be requiring property owners who plan on additions or similar projects of more than 500 square feet to submit a stormwater management site plan to the municipality.
No such stipulation currently exists, but code enforcement and other municipal officials have been attempting to convince home-improving residents to take precautionary measures.
“We’ve been in a number of different situations where we’ve done arm twisting with people and required them to do something so they didn’t kill their neighbor with stormwater after their home was added onto,” Deiseroth, president of Gateway Engineers and a Mt. Lebanon resident, said.
The proposed revision would require applicable property owners to engage a professional to design a management system and then submit the plan to the municipality for approval and subsequent inspection.
“It is a complicated matter to ask people to do,” Deiseroth said, “and I can see people saying that ‘Hey, this is overreaching. We shouldn’t have to do this. We can’t put money into our addition now because we have it on stormwater.’
“There will be calls and there will be pushback from people if this is implemented this way,” he told commissioners. “But right now, we have no way to control this.”
Management plans are likely to include an underground component for gathering stormwater runoff, optimally with an overflow mechanism to tie into the municipal storm sewer system. To make such connections, property owners must seek certain arrangements.
“We’re at least wanting them to make correspondence with their neighbor attempting to obtain that permission and possibly get an easement on the neighbor’s property to carry the stormwater through,” Deiseroth explained.
Pennsylvania’s Act 167 of 1978 required counties to prepare and adopt watershed-based stormwater management plans, and Allegheny County finally did so 39 years later, in December.
The county has provided a model ordinance for municipalities to follow, but that document calls for the requirement of a stormwater management plan to apply to “earth disturbances” exceeding a quarter of an acre, or 10,890 square feet, rather than 500 square feet.
Deiseroth explained that because Mt. Lebanon is 99 percent developed, most projects that increase stormwater runoff are exceedingly smaller in scale than those addressed by the county’s model ordinance.
“If we don’t control it on a smaller level, then we’re never going to get anything,” he said. “People aren’t going to have to do anything. It’s going to continue to be a muddled mess.”
As per the ordinance adoption process, the commission will schedule a public meeting prior to taking a vote.