Four phases over five months.

That’s the plan for the construction of a roundabout at the intersection of Pennsylvania Avenue and Market Street.

Work starts April 3 — that’s Phase 1 — and PennDOT has described in further detail how each of those phases is going to work and, roughly, how long each will take.

“During this phase, a large portion of the roundabout construction will take place predominantly within the existing intersection,” PennDOT said in a statement. “Westbound traffic will continue to use one lane of the existing roadway.”

That phase is expected to take about two months.

“Phase 2 will include opening a portion of roundabout for eastbound traffic on Pennsylvania Avenue,” according to a PennDOT statement. “This phase is expected to take approximately four weeks to complete.”

Phase 3 will then include opening another portion of the roundabout, this time for traffic heading westbound on Pennsylvania Avenue from Market Street. That phase is also expected to last about four weeks.

“Phase 4 is tentatively planned to occur in August,” per PennDOT. “It will include the final layer of paving, final updates to street lighting, as well as landscaping and other finishing work. This work will be completed under normal flagging operations.”

That’s also expected to take about four weeks.

Utility relocation and material acquisition, according to PennDOT, started last year after the contract was awarded.

“When needed, detours for Market Street will use Route 6, Laurel Street, and Pennsylvania Avenue,” according to PennDOT. “As needed, detours for Pennsylvania Avenue will use Route 6 and Ludlow Street. Water Street will also be closed to through traffic for a portion of the work.”