{{Use dmy dates|date=July 2019}} {{Use New Zealand English|date=July 2019}} {{Infobox river | name = Mangapu River | image =File:Mangapu River from Pehitawa bridge.jpg | image_size = | image_caption =Mangapu River from Pehitawa bridge | source1_location = | mouth_location = [[Waipā River]] | subdivision_type1 = Country | subdivision_name1 = [[New Zealand]] | length_km = 48 | source1_elevation = | mouth_elevation = | discharge1_avg = | basin_size = }} The '''Mangapu River''' is a river of the [[Waikato]] region of New Zealand's [[North Island]]. It has its sources in numerous streams which flow generally northwards from the [[King Country]] south of [[Te Kūiti]], the longest of which is the [[Mangaokewa Stream]]. These streams join to form the Mangapu close to Te Kuiti, and from here the river flows north, passing close to the east of [[Waitomo Caves]], where the Mangapu caves have the largest entrance in the North Island<ref>{{Cite web|url=https://www.waikatoregion.govt.nz/assets/WRC/Council/Policy-and-Plans/HR/S32/Part-A/Department-of-Conservation-2014.-Conservation-Management-Strategy-Waikato-20142024-Volume-I-Operative-29-September-2014.-New-Zealand.pdf|title=CONSERVATION MANAGEMENT STRATEGY WAIKATO 2014–2024| volume=I|date=29 September 2014|publisher=Department of Conservation}}</ref> (about {{Convert|100|m|ft|abbr=on}} long and {{Convert|90|m|ft|abbr=on}} deep),<ref>{{Cite web|url=http://bts.nzpcn.org.nz/bts_pdf/Well_1987_43__3-6.pdf|title=The Flora of the Lost World Cavern, Mangapu Caves System}}</ref> before flowing into the [[Waipā River]] at [[Ōtorohanga]].<ref>{{LINZ|39558|Mangapu River|2010-04-21}}</ref>
The New Zealand [[Ministry for Culture and Heritage]] gives a translation of "double stream" for ''Mangapū''.<ref>{{Cite web|url=https://nzhistory.govt.nz/culture/maori-language-week/1000-maori-place-names|title=1000 Māori place names|publisher=New Zealand Ministry for Culture and Heritage|date=6 August 2019}}</ref>
[[State Highway 3 (New Zealand)|SH3]] crosses the river on a {{Convert|111|m|ft|abbr=on}} bridge near Ōtorohanga built in 1966<ref>{{Cite web|url=http://his.aucklandmotorways.net/PDFs//WAIKATO/00006_469_WAIKATO_PSMC006_003_6.pdf|archive-url=https://web.archive.org/web/20170205100023/http://his.aucklandmotorways.net/PDFs//WAIKATO/00006_469_WAIKATO_PSMC006_003_6.pdf|url-status=dead|archive-date=5 February 2017|title=Highway Information sheet 003-0057}}</ref> and near [[Hangatiki railway station|Hangatiki]] on a {{Convert|41|m|ft|abbr=on}} concrete bridge built in 1977.<ref>{{Cite web|url=http://his.aucklandmotorways.net/PDFs//WAIKATO/00007_470_WAIKATO_PSMC006_003_7.pdf|title=Highway Information sheet 003-0063|archive-url=https://web.archive.org/web/20170205095832/http://his.aucklandmotorways.net/PDFs//WAIKATO/00007_470_WAIKATO_PSMC006_003_7.pdf|url-status=dead|archive-date=2017-02-05}}</ref> The [[North Island Main Trunk|railway]] follows the east bank for about {{Convert|6|km|mi|abbr=on}}, crossing only small tributaries,<ref>{{Cite web|url=http://www.topomap.co.nz/NZTopoMap/nz56817/Mangapu-River/Waikato|title=Mangapu River, Waikato - NZ Topo Map|website=NZ Topo Map|language=en|access-date=2017-02-04}}</ref> though it did suffer from flooding, for example in 1905.<ref>{{Cite web|url=https://kura.aucklandlibraries.govt.nz/digital/collection/photos/id/180104|title=Flood waters running through a clock cutting on the railway between Hangatiki and Otorohanga|date=9 November 1905|website=Kura Heritage Collections Online (Auckland Council Libraries)|access-date=2025-06-09}}</ref>
The river at Ōtorohanga is classed as being in the worst 25% of similar sites as regards all measured pollutants,<ref>{{Cite web|url=https://www.lawa.org.nz/explore-data/waikato-region/river-quality/waikato-river/mangapu-river-at-otorohanga/|title=Land, Air, Water Aotearoa - Mangapu River at Otorohanga|website=www.lawa.org.nz|access-date=2017-02-04}}</ref> though some attempts are being made at restoration.<ref>{{Cite web|url=http://www.makearipple.co.nz/Action-groups/ripples/Mangapu-River-Riparian-Restoration/|title=The Ripple Effect|website=www.makearipple.co.nz|language=en-NZ|access-date=2017-02-04}}</ref>
== Pehitawa Kahikatea Forest Reserve == [[File:Pehitawa_suspension_bridge.jpg|thumb|Pehitawa suspension bridge]] The reserve {{Convert|18.5|ha|acre|abbr=on}} of [[Dacrycarpus dacrydioides|kahikatea]] forest on the east bank of the river, was purchased by the [[NZ Native Forests Restoration Trust|Native Forests Restoration Trust]] in 2001. Kahikatea forest once covered {{Convert|41000|ha|acre|abbr=on}} in the Waipa Ecological District, now reduced to {{Convert|158|ha|acre|abbr=on}}, of which {{Convert|52|ha|acre|abbr=on}} are in the Mangapu valley, though over {{Convert|70|ha|acre|abbr=on}} has been felled since 1975.<ref name=":0">{{Cite web|url=https://www.nfrt.org.nz/reserves/pehitawa-kahikatea-forest/|title=Pehitawa Kahikatea Forest - Native Forest Restoration Trust|website=www.nfrt.org.nz|language=en-US|access-date=2017-02-04}}</ref> A major drainage scheme was carried out just upstream from the reserve in the 1930s, including emptying of a lake.<ref>{{cite news|url= https://paperspast.natlib.govt.nz/newspapers/NZH19321108.2.135|title=BIG DRAINAGE SCHEME (New Zealand Herald, 1932-11-08)|website=paperspast.natlib.govt.nz|publisher=National Library of New Zealand|language=en|access-date=2017-02-04}}</ref> The forest floods in winter<ref>{{Cite web|url=http://www.waikatoriver.org.nz/wp-content/uploads/2016/04/TECHNICAL-SUMMARY-FINAL-MARCH-2016.pdf|title=2016 Pilot Waikato River Report Card: Methods and Technical Summary|date=March 2016|publisher=Waikato River Authority}}</ref> and flood protection would be uneconomic.<ref>{{Cite web|url=https://www.waikatoregion.govt.nz/assets/PageFiles/22974/Waipa_Zone_Plan.pdf|title=Waipa Zone Management Plan|date=April 2012|publisher=Waikato Regional Council Policy Series 2011/17}}</ref> Some kahikatea in the reserve are about 120 years old. The reserve also has [[Syzygium maire|swamp maire]], [[Prumnopitys taxifolia|mataī]], [[Alectryon excelsus|tītoki]] and [[Laurelia novae-zelandiae|pukatea]].<ref name=":0" /> [[Te Araroa]] long-distance walkway passes through the reserve and crosses the river on a [[Simple suspension bridge|suspension bridge]].<ref>{{Cite web|url=https://www.teararoa.org.nz/waikato/pehitawa-track/|title=Pehitawa Track:Te Araroa - New Zealand's Trail - Waikato / King Country|website=www.teararoa.org.nz|language=en|access-date=2017-02-04|archive-date=23 January 2020|archive-url=https://web.archive.org/web/20200123120347/https://www.teararoa.org.nz/waikato/pehitawa-track/|url-status=dead}}</ref>
==See also== *[[List of rivers of New Zealand]]
==References== {{reflist}}
==External links== * [http://riverlevelsmap.waikatoregion.govt.nz/cgi-bin/hydwebserver.cgi/points/details?point=799&catchment=17 Flood levels at SH3 bridge near Hangatiki] * [https://www.google.co.nz/maps/@-38.1954996,175.2050049,3a,75y,332.5h,63.89t/data=!3m6!1e1!3m4!1sl7WXua9RzjnO776-AE4z_Q!2e0!7i13312!8i6656?hl=en Google Street view of the river at SH3 bridge near Ōtorohanga] * [https://www.google.co.nz/maps/@-38.2465299,175.1817104,3a,75y,124.48h,70.72t/data=!3m6!1e1!3m4!1sGVc6ifFWsfFVnqLGBHv6hA!2e0!7i13312!8i6656?hl=en Google Street view of the river at SH3 bridge near Hangatiki]
{{coord|-38.193537|175.203708|region:NZ_type:river|display=title}}
[[Category:Waitomo District]] [[Category:Rivers of Waikato]] [[Category:Rivers of New Zealand]]
{{Waikato-river-stub}}