The New Zealand Transport Agency, police and contractors working on the Baypark to Bayfair Link say too many people are speeding through the area, putting lives at risk.
Agency project manager John McCarthy said not everyone was adhering to the 50km/h speed restriction through the site and there had been "a number of minor crashes through the site due to speeding and driver inattention".
"The temporary traffic management has narrowed lanes, providing less time to react to other vehicles, and a reduced speed is required to keep road users and workers safe."
Since August 2017 there have been 36 crashes within the Bay Link project site. Of those, 11 per cent of the crashes were a result of speed, and 75 per cent were a result of driver error, namely following too closely, failing to notice the car in front was slowing, and failing to give way.
McCarthy said due to the narrower lanes, the potential for both worker and motorists to be harmed was greater.
Vehicle activated speed signs will be installed this week to monitor motorists' speed through the construction site and from July 16 the screens will flash up vehicle speeds.
Project contractors, CPB Contractors, are working on the site - which is expected to reduce congestion and improve safety by separating local and state highway traffic.
Project manager Stephen Wright said there was a team of 80 involved on site.
"Our workers have a right to a safe workplace and drivers need to play their part in providing it.
"We ask that road users make good decisions to protect the road workers – they are mums, dads, sons, daughters, loved family and friends."
Twelve-year-old Finley Smith, whose father works for CPB Contractors, has added his voice to those concerned about speeders. Finley's message to drivers was: "Please slow down when you're driving through the roadworks".
"I want my Dad home safe."
Western Bay of Plenty head of road policing Senior Sergeant Mark Pakes said officers would be watching road user behaviour in the Baypark and Bayfair area.
"Temporary speed restrictions are enforceable. This is a busy area of Tauranga and road users must watch their speed and keep a safe following distance."
The key features of the project include the construction of two flyovers and improvements to the SH29A and Truman Lane roundabout, and the SH2 Maunganui-Girven roads roundabout.
It is expected to be complete late 2020.