A state grant will fund a study that could lead to a healthier Monponsett Pond. The town received $65,238 through a Massachusetts Office of Energy and Environmental Affairs program aimed at easing ecological damage at reservoirs. Town Administrator Charlie Seelig said the town has until the end of June to complete a study of the pond, which hosts a boat ramp and beaches, and is also a reservoir for Brockton, which can draw up to 25 million gallons a day from it from October to May. “There’s been a definite change in the water quality over the years. It’s not as clear. We’ve also had a significant increase in plant growth,” said Seelig. He noted that the town has banned boating and swimming in the pond the past two summers due to algae growth.