Kapiti Coast resident Lynn Sleath told Fairfax there was "an obvious connection" between the closure and the level of traffic on the road in the past few days.
"I'm watching all these people driving in their cars and some of them are going to Taupo and distances away, but a lot are just doing local trips, and a lot of those folks could be on the train," Sleath told Fairfax.
He said while the work at Paekakariki seemed "perfectly reasonable", it was going slowly and would have been better done overnight.
"If this was Wellington airport runway, or a state highway being repaired, they'd get it done quickly, they'd minimise the disruption," Sleath said.
Sleath told Fairfax the bus service was often not running to schedule because of the traffic mayhem, with 11 online messages sent to him on Tuesday alone, alerting him to delays.
Fairfax said another commuter had to change buses three times on a trip between Kapiti and Wellington because of the closure.