Among the capital improvement projects slated for 2014 in Riverside was resurfacing the main commuter parking lot next to the downtown train station. But that project has been put on hold by the village board in order for village staff to research whether or not Riverside should seek green options for resurfacing its parking lots moving forward.

On Oct. 17, trustees agreed to defer the commuter lot resurfacing until 2015 after Public Works Director Edward Bailey gave the village board a report outlining options for repaving the lot with asphalt only, permeable pavers only or a combination of the two.

While a simple asphalt resurfacing would have cost about $318,000, a purely “green” solution could cost as much as $725,000, according to Bailey. However, an asphalt lot would need to be resurfaced in about 15 years, while a lot constructed of permeable pavers would have a useful life of about 50 years, said Bailey.

Riverside in 2011 submitted a grant application to the state to fund a commuter lot resurfacing project that included permeable pavers, but failed to obtain the grant.

The question comes down to deciding whether to pay higher upfront costs or capture savings over the life of the improvement.

“With any green infrastructure project, this is typical,” said Village President Ben Sells. “The upfront cost appears to be more, but when you take into account the lifetime of the project you see the savings come through.”

Although an asphalt lot would cost far less initially, the cost related to the lifetime of the improvement favors the green solution. Per year, the construction cost of paving the commuter lot with asphalt is about $21,000 over its 15-year lifetime. A green solution to the commuter lot would cost about $14,500 per year over its 50-year life.

In all, the village owns nine parking lots in and around the central business district, several of which can be rented by residents and two of which can be used by commuters. Presently, all but one of the lots are paved with asphalt. The village’s “green” parking lot, which has permeable pavers, was built at 61-63 E. Burlington St. in 2012 and funded largely by a state grant. That lot cost $575,000 to construct.

The other consideration, according to Bailey, is taking into account how much storm water runoff would be retained onsite at a green parking lot. With a traditional asphalt lot, that water is directed to the sewer system, which is already strained to capacity and surcharges during heavy storms, flooding basements in the village.

“Green infrastructure I think almost certainly has to be part of a solution to our whole under-capacity sewer system,” said Bailey. “Parking lots are designed to sheet all of that water off the parking lots into the streets and sewer system.”

Bailey said he was working with the village’s engineering firm, Christopher B. Burke & Associates, to get estimates for green solutions for three other parking lots the village owns and which are in disrepair — the lot next to the police station, the lot next to Riverside Garage and the lot along Park Place.

Village Manager Peter Scalera said that part of the engineer’s report will include a cost-benefit analysis taking into account how much storm runoff would be kept out of the sewer system by installing green parking lots.

But even if the case can be made to go green, the village will still be faced with the issue of funding the more expensive solutions up front.

Sells floated the idea of seeing whether the village might be able to use water/sewer reserves to fund the parking lots, since the storm runoff from those lots affects sewer capacity. However, it’s unclear whether those funds could be available for such a purpose.

The village also could use revenues from commuter parking fees to help pay off construction costs or seek funds through a referendum.

Finally, Sells said that at a recent meeting with Chicago Wilderness, a regional conservation organization, he said other grant funding might become available for green infrastructure projects.

“As this conversation moves forward over the next year or two, there is an opportunity we also might be able to get grant funding for these projects,” Sells said.