State Highway 23 (New Zealand)


State Highway 23 is a New Zealand state highway that connects the towns of Raglan and Hamilton.

Route

SH 23 commences in the Hamilton suburb of Frankton at the intersection of Massey Street and . It travels west down Massey Street, changing to Whatawhata Road after a six-leg roundabout in the suburb of Dinsdale. After exiting Hamilton, and reaching the town of Whatawhata it shares a brief concurrency of the north–south and crosses the Waipa River. It then continues west over the summit to the Waitetuna valley, through Te Uku and over tributaries of the Whaingaroa Harbour, all the way to Raglan where it terminates on Main Road on the approach to the township.

Traffic flows

records taken by the NZ Transport Agency measures the volume of traffic is measured at roughly 13000 vehicles per day near the eastern terminus while at km 32 closer to Raglan the AADT is measured at roughly 4500 vehicles per day. SH 23 is classified by the NZTA as a primary collector highway as per the One Network Road Classification.
Traffic roughly quadrupled over the period 1975 to 2018, as shown in this table and the graph derived from it.
Location19751976197719781979198019811982198319841985198619871988198919901991199219931994199519961997199819992000200120022003200420052006200720082009201020112012201320142015201620172018
20m West of Hawk St129301226012610124801241912512130041293111414109671089811459111901136011805122571285113004
40m East of Newcastle Rd, Dinsdale3130305057209760973094501000010220103659720110011036010389106961003710402108421071111008119281185412676
880m East of Kakaramea Rd, Whatawhata170016501800129013201660237024502750319021003000310036503700397043804380465047104980506049684995511046424893535547455301499556215743627463706396
200m West of Maori Point Rd, Whatawhata4720527053405640591057715918628460486328645267866235601364296350752275257393
90m East of Wrights Rd, near Te Uku1070103083011001100980100010502250107014801520176017501600167019002350245027102850291030502990356035783517366234633713373135083745365536284102475847754238

from Karamu Walkway

Route changes

When SH 1 used to run through the Hamilton CBD, SH 23 began at the intersection of Mill Street and Ulster Street. When SH 1 was diverted westwards away from the CBD SH 23 was shortened to where its eastern terminus currently lies.

Speed limits

limits apply at Whatawhata and Te Uku.

Safety

In the decade to 2016 there were 10 deaths and 64 serious injuries on SH23. 30% hit a roadside hazard, 40% hit an oncoming vehicle, 25% were at junctions, 47% involved alcohol and 48% driving too fast. Work by the Safe Roads Alliance in 2016/17 on 2 of the 3 sections of road is estimated to cost $13.2m.

Public transport

A public bus service which traverses the length of SH 23 is provided by Waikato Regional Council.

History

The road was gazetted a State Highway in 1961. In the same year tar-sealing of the road was completed. Prior to that, metalling had been completed in 1921.
Until 1863 the route was only passable on foot. By 1864, as part of the invasion of the Waikato, about six bridges were built to make it passable for pack horses. Conversion to a road began in 1878 and the first stage coach ran in March 1880, though the bridge over the Waipa wasn't started until late in 1880. Metalling of the road began after a poll in 1907 and deviations were built to shorten the route, including that over the summit, bypassing what is now Old Mountain Road, which was passable by 1912.

Major intersections