WESTBROOK — Planning officials from Westbrook and Portland are meeting this week for talks on the potential traffic and stormwater impacts from the proposed 500,000-square-foot Dirigo Plaza shopping center, which will straddle the city line. 

At issue is how the site, formerly owned by Pike Industries, will impact surrounding traffic, especially at aging intersections that are already in need of improvements. 

The project is expected to generate a lot of traffic. An early estimate last year from Jeff Dirk, a traffic engineer working on the J&J Gove Development team, said the plaza is expected to produce some 2,400 “new trips” on a peak weekend afternoon.

For the two cities that means taking a look at some key intersections. 

According to Jennie Franceschi, the Westbrook city planner, these include the intersection of Main Street and Larrabee Road, and the Portland intersection where Maine Turnpike Exit 48 meets Riverside Street and spills into Larrabee Road. 

Developers will present both cities with their traffic study findings and proposed intersection upgrades on Tuesday, May 17, at 7 p.m. in room 114 of Westbrook High School.

At Exit 48 in Portland, Franceschi said details will be discussed on how to improve the intersection, which is complicated.

“This project won’t be the cause of all of that intersection’s woes, but we will try to improve an already tricky situation,” she said.

Another intersection to be looked at by Portland is Riverside Street at Brighton Avenue. 

Portland planning staff will be present at the meeting, along with the city’s full-time traffic engineer. Also reviewing the traffic plans are engineers from the city of Westbrook and the Maine Department of Transportation, which has final say on what improvements need to be made. 

“There are a lot of eyes on it, as there should be,” Eric Dudley, Westbrook’s director of public services and engineering, said. “We knew this was going to be the biggest piece of the puzzle.” 

“The ultimate approval comes from the Maine Department of Transportation,” Westbrook Planning Board Chairman Ed Reidman said. 

Community discussion about the project increased last month when it was reported that Wal-Mart would be one of the anchor tenants. Many residents in Westbrook have shared vocal criticism since the announcement, while others have defended it. Some have said they plan to attend Planning Board meetings to air concerns. 

Reidman said that while Tuesday’s meeting is a workshop intended to inform the public, the choice of Dirigo Plaza’s tenants will not be discussed. 

“I do know that the selection of stores will not be a topic,” he said. “I expect that when we have a public hearing, but there’s nothing the board can do about the selection of stores.” 

The shopping plaza will be entirely in Westbrook, but a large pit that has been used for decades as a quarry by Pike Industries falls right on the Westbrook-Portland line. The property is 81 acres, including the 20-acre gravel pit.

Also on the agenda Tuesday will be further discussion of the site’s stormwater runoff, which is complicated by the large pit. Officials from both cities have been discussing drainage for the site; developers have proposed allowing the 350-foot-deep pit to fill with water, creating a large pond.

Franceschi said that because the project uses land in both communities, Portland has to have a subdivision review process. She said they are also reviewing the proposed path around the pond. 

Reidman said he believes the developer has already been working with Portland to discuss drainage plans, which include upgrades to Nasson’s Brook, which runs through the property. 

At a Westbrook Planning Board meeting on May 3, Wayne Morrill of Jones-Beach Engineers, part of the development team, said they will be replacing an existing culvert in the brook. The stormwater impact and related modifications must be approved by the Maine Department of Environment Protection. 

With Pike Industries all but finished on the property, the pit has already begun filling with water, which Morrill expects will take a few years to fill completely. They may also add water themselves as part of the site work.

Developer Jeffrey Gove has said the pond will be a focal point of the development, with planned walking paths circling the perimeter and the potential for hosting events such as fishing derbies. He said he expects more tenants to be announced over the next few months. 

A backhoe dumps dirt last week at the Pike Industries gravel pit, which will eventually become a pond and focal point of the proposed Dirigo Plaza shopping center in Westbrook. The land straddles the Westbrook-Portland line and officials from both cities are taking part in the review process.Officials from Portland will be involved in the Dirigo Plaza review process, because the large gravel pit and several surrounding intersections will be impacted. This intersection, at Riverside Street and Brighton Avenue, will also most likely receive upgrades.