The likely speed reductions would cover Farndon, York, Arataki, Kirkwood, Percival, St Georges and Chatham roads.
Eastern Police road policing prevention manager Senior Sergeant Dan Foley was "all for the suggested changes".
"We are happy that those are good speed reductions that will make those pieces of road safe.
"Farndon Rd in particular (which has seen 22 crashes, including two fatal crashes, in five years) is a dangerous piece of road and an 80km/h speed limit through there will save lives. In fact all of those speed reductions are all about decreasing the chances of serious crashes, loss of life or serious injury.
"There are a lot of roads in New Zealand that have a 100km/h speed limit but are probably not fit for someone to drive at 100km/h."
Farmers Transport Hastings branch manager Nigel Parker said the company was fully behind the move.
Although it would raise some costs, the company would "happily suck up those costs" to improve safety for the community, he said.
"I think it's a good thing to be honest, with the way the building industry and the way the whole area is growing. We need to be very mindful of the amount of people around.
"The more infrastructure the council can put on the roads and reduce speed limits the better it is for everyone's safety."
Local truck driver and former traffic cop Trevor Elmers also agreed.
"I travel a lot on York Rd during the daytime and I find that the speed limit should be lowered [even further] to 70kmh as there are quite a few driveways hidden by hedges."
Cycling Action Network spokesman Patrick Morgan praised HDC for being "ahead of the game" in the safety sphere.
"If you have an expressway, then by all means, the speed limit can be 100km/h but on a narrow country road that's populated with people on bikes and pedestrians then we think 100km/h is not the appropriate speed limit."
Lower speeds would have a positive effect on road safety for cyclists and motorists.
"It's hard to argue with physics - and it also makes very little difference to travel times because that's mainly determined by driving conditions rather than the speed limit.
"The council is really taking a leadership position on this and it's really consistent with the Government's desire to eliminate deaths and serious injuries on our roads."