HAMPDEN – Town councilors authorized on Monday a public hearing to discuss the town’s flood-plain management plan, which state officials said is outdated and, without adjustments, could prompt residents to lose their flood insurance.

Investigating a request to place some fill along a private property on Maine Road North, Hampden code enforcement officer Ben Johnson recently found the ordinance governing development in areas subject to flooding “is in need of critical updates,” he said in a letter to councilors.

Hampden’s ordinance hadn’t been revised since it was enacted in 1988, and failure to adopt and comply with the changes could prevent Hampden residents from getting flood insurance through the Flood Management Program, according to the letter.

State officials have given the town six months to comply.

Town officials are already preparing to make the necessary changes and said it’s largely a matter of approving a boilerplate document provided by the state.

The proposed ordinance document is only three pages longer than the previous document, said Councilor Thomas Brann.

He said the most substantial changes are wording that would bring the town into compliance with laws that weren’t in place when the first ordinance was passed. Councilors are also considering changes to the town’s sewer ordinance after effluence flowed into a new Patterson Street home on April 14 after the town flushed the system.

A simple back-flow valve could have prevented much of the damage to the home, and councilors are considering wording that would require such devices to be installed when new homes are built.

Town Manager Sue Lessard said requiring the valves in all Hampden homes would be too much to ask, as would using a special camera to check every pipe for blockage.

The council is expected to discuss with its Public Works Department in the coming weeks better ways to locate potential problems.

In the Patterson Street case, a specialized camera sent down through the pipe showed that tree roots were responsible for a full blockage in the pipe near where the new home was connected.