The testing revealed 99.4 per cent of the traffic observed during tests travelled at less than 40km/h and all traffic was recorded travelling at less than 50km/h - the legal speed limit for the area.
Council officers were unable to find records of an accident involving a young girl - who petitioners said was struck by a car late last year but was not injured.
Senior roading engineer Rui Leitao said not all accidents got reported to police and that council could only make decisions based on what was officially reported.
"During the last 17 years there has been one reported non-injury crash involving a vehicle hitting a parked vehicle," Mr Leitao said.
"In terms of crash risk, this section of road is considered low risk."
He said schools within 50km/h urban areas, where speed was determined to be
an issue, the chosen solution has been to erect high visibility 40km/h advisory speed signs.
"Due to Portal Street's road classification and purpose, speed bumps aren't recommended."
The signs would cost $4000 and would be funded by the New Zealand Transport Agency. Advisory signs were speed recommendations and the speed limit passed the school would remain at 50km/h.
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Councillor Charlie Anderson thought 40km/h was too fast. "I wouldn't go through at 40 - I was thinking 20."
Graeme Young said a speed restriction slower than 40km/h was "utter nonsense" and pointed out the speed tests which showed no speeding traffic.
Hadleigh Reid described the proposed signs a "sensible good cheap get-it-done solution."