HOKITIKA RIVER MOUTH BRIDGE LENGTH STUDY

A new highway project is to re-route SH6 so as to bridge the Hokitika River near its river mouth some 4 km downstream of the existing bridge. At this tidal site the natural river width of 850 m is considerably wider than upstream. The study examines whether a shorter bridge and causeway would provide an adequate waterway. A design flood size at the site was determined from various rainfall and river flow records. This included briefly establishing two water level recorders to correlate flow with another recorder site, and also to examine tidal effects. Backwater analysis was then used to examine the hydraulics of various bridge waterway options. The tide was found to have little effect in design flood conditions. A bridge length of less than half the natural river width was assessed as providing similar hydraulic conditions as the existing situation, and thus was recommended.

• Corporate Authors:

  Institution of Professional Engineers New Zealand

  158 The Terrace
  Wellington,   New Zealand 
• Authors:
  • Williman, E B
  • Crossen, L C
• Publication Date: 1989-3

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 15-21
• Serial:
  • Transactions of the IPENZ
  • Volume: 16
  • Issue Number: 1/CE
  • Publisher: Institution of Professional Engineers New Zealand

Subject/Index Terms

• TRT Terms: Channels (Waterways); Design flood; Highway bridges; Hydraulics; Hydrology; Impacts; Length; Recommendations; Tides
• Old TRIS Terms: Tide effects
• Subject Areas: Bridges and other structures; Highways; Hydraulics and Hydrology; Research;

Filing Info

• Accession Number: 00486081
• Record Type: Publication
• Files: TRIS, ATRI
• Created Date: Aug 31 1989 12:00AM