Henniker voters approved virtually everything at Town Meeting including the latest in a long series of steps to limit how often ponds in town turn a nasty, and potentially dangerous, green.

“We’re lucky, we haven’t had any illnesses … but Keyser Pond has had measurable levels of the toxin,” from cyanobacteria blooms, said Mark Mitch, chairman of the town Conservation Commission. By a margin of 87-5, voters approved a $100,000 warrant article to continue work finding sources of the excess phosphorus that gets into Henniker’s four main ponds, fueling a population boom among the single-celled organisms that release toxins when they die.

Mitch pointed out that the blooms are becoming more common in town, to the point that some people who own shoreline homes are getting property tax abatements from diminished value.

The cost of the work will be covered by the state’s Clean Water Revolving Fund. The next step after identifying sources of excess phosphorus, such as agriculture runoff or leaking septic fields, will be to find ways to limit their impact.

Also during the two-hour meeting, voters approved a budget of $6.66 million, up 6% from the amount approved last year. A proposed amendment to trim $18,000 from the total, the amount it will cost to add 7 ½ hours a week to one town hall position and raise it to full-time, was rejected by a show of hands.

The only warrant article that failed was a petitioned request to increase the amount of income and assets that a person over 65 could own and still be eligible for an elderly exemption on their property taxes. Alexis Deruisseau said she proposed the article because the current limits, including net assets of $84,000 not including primary residence, date to 2007.

“It’s time to bring it up to date to 2024,” she said.

Several speakers sympathized with the financial burden of retired people but balked at indirectly increasing the tax burden on others, and questioned how the proposed changes, such as raising the maximum asset level to $400,000, were determined. One urged the select board to study the matter and bring a proposal back to voters later.

Christine Johnston was among those who opposed the article but sympathized with its goal of helping retired people stay in their homes. She pointed to the state’s tax structure as an underlying issue.

“The fact that we rely solely on property tax … unfairly burdens people who are past their earning years,” she said.

The town tax rate is estimated to increase from $6.93 per $100,000 of assessed valuation to $7.52, adding about $180 to the annual tax bill of a $300,000 home. However, Diane Kendall noted that the estimate is a maximum and may not happen, depending on factors such as leftover income. As an example, she pointed out that last year it was estimated that the tax rate would rise more than 50 cents but it ended up not rising at all.

Voters approved a petitioned article that would eliminate rental fees for using town property from organizations “whose efforts benefit residents of Henniker,” and approved, 85-3, a 20-year bond for $1.5 million in upgrades to the town’s wastewater treatment system, $425,000 of which will be covered by the state’s revolving fund loan program.