JOHNSON CITY, Tenn. (WJHL) — Johnson City could have big staffing shake-ups early next year as just under 60 employees evaluate whether to accept retirement incentives offered earlier this month.

Town officials have long anticipated a so-called “silver tsunami,” a wave of longtime employees retiring all at once.

Offering these employees benefits to retire by Feb. 28 will help the city make plans for their retirement.

“It’s like controlling the water over a dam,” City Manager Cathy Ball said when presenting the proposal to the City Commission on Dec. 16. “If we allow a certain amount to flow out then we know what we have in there and we’re able to manage with that level.”

Employees who’ve worked for Johnson City for 30 or more years are eligible. Among the 58 total employees eligible are eight of the city’s 21 department heads.

City commissioners approved the early retirement plan and notified employees they have until Jan. 31 to make a final decision.

Those who take the offer will retire on Feb. 28, giving the city a month to plan for their departure.

“People who choose that, we’re going to know we’ve got to start focusing on where we need to transfer that institutional knowledge, where we need to start making that succession planning,” Assistant City Manager Randy Trivett told News Channel 11.

“It is an incentive that would tell us that [those who don’t accept are] going to be here another year or two years, because they are foregoing six months of salary to stay with us,” Trivett said. “So that helps us to know that we can postpone the planning or work toward that secession plan in the future.”

Ball told the City Commission earlier this month that junior employees leaving the city have often cited lack of advancement opportunities as a reason for leaving, making the retirement incentives not only critical for planning but helping the city build its future workforce.

Trivett said building up a younger workforce is also critical as the city faces rapid growth.

“By us growing at such a fast pace, it makes the city departments workload grow, and so it’s growing exponentially and when that happens, we’ve got to have people in place who can continue to move forward,” Trivett said.

Those who accept the offer will receive a one-time payment of six months’ salary. Employees who opt-in will also be able to stay on the city’s health insurance along with their dependents until they turn 65 or gain insurance through a new employer.

Vacant positions will be held open until July 1.