AYER -- A new type of investment for retirement benefits could hit this spring's Town Meeting warrant, as selectmen received a detailed pitch last Tuesday night about the benefits of investing in a state trust fund.

Paul Todisco, senior client-services officer for the state's Pension Reserves Investment Management Board, explained how Harvard, Hingham, Boxford and other towns have invested in the irrevocable trust fund set aside for other post-employment benefits, or OPEB.

OPEB funds manage the liability for benefits of future retired town employees, a funding problem that has raised growing concerns nationwide.

The State Retiree Benefits Trust Fund invests those OPEB funds with a yearly return Todisco estimated at about 8 percent.

Todisco said there is risk in investing, but added that municipal trust funds are usually very conservatively managed.

"This is a pension fund and it does have a lot of risk to it because it's a growth fund," he said. "But over time it's outperformed and performed in excess of our expectations."

The town already has OPEB money invested in a mutual fund, Town Accountant Lisa Gabree explained, and is already taking a risk. Numbers from Treasurer Stephanie Gintner show the town earned about 6 percent interest in 2013, noting that the amount the town put in is not going to earn as much money as if it had billions of dollars -- which the state trust fund has.

"This is why I think that this fund is a very viable option for the town," Gabree said.

Todisco said since the fund is from the state, it is nonprofit. Each participating town does, however, pay a management fee that he said is very minimal.

Voters would have to approve an amended version of the necessary state law and authorize the treasurer to invest in the fund at Town Meeting. With the deadline for warrant articles set for April 11, it is still possible the item could land on the warrant list.

In other business:

* Selectmen also heard an update from Mark O'Hagan, one of the developers of Willow Road Development LLC. The company, which is constructing the Willows neighborhood, previously came into the spotlight when the town discovered it owed $250,000 to help pay for the construction of a water tower.

Since the last meeting before the board, O'Hagan said four houses had closed. The town can now receive $48,000 for the water-tower fund, as O'Hagan had agreed to give the town $12,000 for each house that closed. The development has about 21 unsold units, he said.

* Selectman Jannice Livingston said the board had to put an increase in business-certificate fees on the warrant before adopting a change. Selectmen had previously voted to increase the fee from $15 to $30 for four years.

Livingston said with the help of secretary Janet Lewis, the issue will get taken care of. But she said it was disturbing that this was talked about for months, but nobody did anything.

"I'm sitting in between two people who have been a part of the board for quite some time," she said, referencing Selectman Pauline Conley and Chairman Gary Luca, "and how this got past you two, I don't know."

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