Gladstone Bridge Widening

LOCATION Gladstone Road, Gisborne    PRINCIPAL Gisborne District Council   PROJECT DATES August 2018 – July 2019

Bridge widening of the Historic 1925 Gladstone Bridge (originally built using wood in 1885).

A 1.5m widening to provide a shared path using prefabricated cantilevered concrete slabs.  The 1.5m widening extends the width to create a 3m shared cycle and pedestrian path.

Structure:  Works involve demolition of existing concrete balustrade, widening bridge footpath with precast deck slabs, precast concrete balustrades to 2no. spans and steel balustrades to 6no. spans, external beam strengthening and reinforcing of overtopping concrete to footpath for increased centilever loading.

Health & Safety:  The site specific Health and Safety Management Plan is implemented and observed in accordance with the company’s secondary level requirements for ACC WSMP. The project was completed without incident.

Environmental Management: A comprehensive project specific Contractors Social and Environmental Plan was developed and implemented. The works involve demolition and concreting over a sensitive waterway.

Full scaffold platform lined with filter cloth was erected under the work zone to collect and retain any small piece of demolition material that may fall from the work zone. Existing surface water outlets on the bridge were bunded and residual water diverted to a settlement area. All concrete from demolition works is recycled for later reuse within local infrastructure works.

CSL understands the direct impact and lasting effects construction works can have on the physical environment and are proactive in ensuring no contaminants enter the water way and minimal physical disturbance is made to Turanganui river, banks and associated fauna.  There were no environmental issues.

Earthworks:  Excavation and backfilling/hardfill of approaches carried out with smaller plant due the number of underground services present.  Further works involved demolition of existing balustrades and reinstatement of subgrade and concrete slab.  CSL redesigned approach excavations to minimise risk of service disruptions.

Traffic Management: A traffic management plan was in place for the duration of the project which included a speed restriction of 30 km/hr along and restricted access onto adjoining roads.  Approach signage was installed in both directions, VMS boards, and stop/go set-ups during precast landing were in place.    Live traffic was adjacent to the work, this being one of the region’s busiest roads with the bridge carrying 21,000 vehicles per day.  The physical bridge construction zone is isolated using 2m temporary barriers for protection of the worksite.  This demonstrates CSL’s ability in working in and around a high trafficked corridor within the site boundaries.

Liaison with Affected Parties:  The bridge is a NZ Heritage listed structure and regulations/requirements surrounding the final aesthetics of the bridge were in conflict with public and public office opinion.  CSL negotiated and presented a solution which was better suited to meet all parties requirements in aesthetics.  This was approved and implemented. This demonstrates CSL’s cooperative approach to progressing contracts and ability to be adaptable and flexible.