While going “green” may be all the rage, the message hasn’t necessarily filtered down to the companies traditionally expected to perform municipal infrastructure projects.

Riverside has had a rough time getting traditional paving and concrete contractors to submit competitive bids for the two green infrastructure projects – a pair of alleys and a parking lot – they’d like to complete this summer.

After rejecting the two bids it received in April, Riverside re-bid the projects – and still found that their estimates were lower than the bids they ended up receiving.

On May 9, Riverside opened four bids for the projects, which involve the installation of permeable pavers to create two green north-south alleys between York and Kent Roads near Harlem Avenue and the construction of a green parking lot at 61-63 E. Burlington St. in the downtown area, also using permeable pavers.

The village’s engineering firm estimated that the cost of the two projects would be roughly $550,000, an estimate revised upward from $541,000 after the first round of bidding.

But the low bid came in at $575,000, while the high bidder topped out at $1,051,000.

That was somewhat better than the two bids the village opened in April. In the first round of bidding, the low bid was $689,069 while the high bid was $1,088,451. Village trustees rejected those bids on May 7.

“What we learned from all of the bidders is that these are very unique projects, with a mixture of materials to be used,” said Village Manager Peter Scalera. “Some felt that it was more work than they had time for right now. They’re looking for more straightforward projects.”

In fact, the low bidder in the second round was not a paving company but a landscaping firm, Elk Grove Village-based Great Lakes Landscape Design.

“It’s a different sort of project that a lot of concrete and paving companies aren’t accustomed to,” said Scalera. “Until people become more comfortable working with [green materials] the prices will be higher.”

Scalera said the narrow alleys in particular posed a problem for the paving companies, who said they couldn’t use some of their larger equipment in the confined spaces and would have to rely more on manual labor.

The challenge now for Scalera is coming up with the additional funds needed to get the projects moving. The majority of the money for the work is coming from a $502,663 Illinois Green Infrastructure grant.

The balance will likely come from a combination of sources, including the village’s parking lot fund, motor fuel tax money and the capital projects fund.

“We’re trying to determine a recommendation on where to pull that money from,” said Scalera.

He said he expects to have a recommendation for the village board to vote on at their May 21 meeting.

Despite the higher cost of the green projects, Scalera said the village will seek green infrastructure solutions moving forward.

“It’s worthwhile to go down this path. Once these are completed we’ll be happy with the result,” said Scalera. “We’ll continue to look at projects to see if they can use green materials, whether it’s the commuter parking lots or other alleys.”