The master plan for the proposed Collins Ridge development in Hillsborough was approved by the Board of Commissioners at its meeting on Monday night.

Hillsborough Mayor Tom Stevens says that the developer has altered its plan to include more affordable housing after several public hearings.

“We had concerns about the level of affordable housing,” Stevens said. “The developers had originally proposed something like 40 units and then they came back when we just didn’t feel like that was adequate.

“They couldn’t do that with units for sale, but they came back [and] working with CASA we could do rental units.”

Stevens says by working with Community Alternatives for Supportive Abodes, CASA, the developer will be able to provide 88 affordable rental units.

The Collins Ridge project would be located on about 125 acres on the eastern end of Orange Grove Street in central Hillsborough.

The master plan, which has now been approved, states that no more than 1,038 units will be permitted on the property.

The town’s planning board had recommended that the master plan be approved with specified conditions, and Stevens says most of the continuing concerns will be handled as the developer moves through the remaining approval process.

“[The master plan] specifies a little bit about the streets, what kind of amenities would be done,” Stevens says, “but it isn’t a specific plan for each one of those parcels.”

Stevens says now that the master plan has been approved, the developer will have to come back to the board and apply for a special use permit.

“That would have a lot more details about lighting and where specifically the roads are and how many units and what setbacks were,” Stevens says of the potential Special Use Permit. “A lot of those things that are of concern we really won’t even see until the SUP.”

Stevens says another concern has been the amount of traffic the development would add to the historic town continues as it continues to expand housing availability.