Dormer Construction

Parklands Gravity Sewer Part 2

October, 2016

SCOPE

The Beach Road sewer line sustained major damage during the earthquake and needed to be replaced.

Dormers won the open tender with FCC.

The contract was made up of a main line at 700 meters long of 225mm-300mm PVC sewer pipe between 2.5 to 4.5 meters deep, plus 300m of 150mm collector line.

The whole project required dewatering due to the high water table, well point dewatering systems was used to deal with this.

The connection to the new Pump Station Receiving Manhole required Dormers to come up with a solution that required a one off special 500mmPE fabricated pipe special, as the connection was not standard.

Bypass pumping was also required to be able to bench the manholes due to the high volumes of flow down the line.

Once the new lines were operational we grouted the old lines and re benched the manholes while dealing with the live sewer flow.

PERFORMANCE

Environment

There was considerable ground water that was dewatered and discharged down the Stormwater lines, and then into the Travis Wetlands. So we had to make sure that the discharge water was clear and wouldn’t affect the Wetland.

Health and Safety

We had no Health and Safety issues. This was a credit to the team as this was a one year project, including deep excavations and confined spaces.

Programme

The project was completed in the programed time frame.

Cost/Budget

The project was completed with no major cost escalations. Small variations were completed by open negotiation between FCC & DCL management teams monthly.

ESTUARY ROAD DRAINAGE WORKS

August, 2014

SCOPE

This project consisted of four separate SCIRT contracts.
Work involved the construction of approximately 2.3km of sewer main, 1km of collector main, 4 pump stations, significant bypass pumping, lateral connections, testing and surface restoration.

Scope of works generally involved; all setting out of main pipeline (stormwater and sewer), temporary trenching, dewatering, cutting, excavation, penetrometer testing, lateral connections, junctions, trench and service support, haunching, associated manholes, backfilling and compaction.

PERFORMANCE

Environment

Complied with SCIRT, Environment Canterbury and Christchurch Council requirement at all times for sediment control and methodology. Dormer received positive feedback from residents of the streets where construction was undertaken.

Health and Safety

No serious safety incidents.

Programme

Achieved programme and quality of work. (Dormer’s first contract for sewer renewal on Estuary Road was extended to include 3 further contracts).

Cost/Budget

Measure and value, approved variations.

SCIRT WORKS

August, 2014

SCOPE

Dormer has completed a large number of projects awarded under the SCIRT alliance and continues to add projects to this portfolio of work.  Typical scope of works includes all setting out of main pipeline (stormwater and sewer), temporary trenching, dewatering, cutting, excavation, penetrometer testing, lateral connections, junctions, trench and service support, haunching, associated manholes, backfilling, NDM compaction testing and restoration. In some cases Dormer were responsible for the construction, installation and commissioning and testing of pump/lift stations.
Overall approximately 4,000m of waste water piping ranging from 150mm to 375mm diameter and  approximately 1000m of stormwater ranging from 285mm to 1800mmm (depth range  1.5m to 4m) , over 200 manholes  and 10 lift stations has been installed by Dormer across Christchurch city. Significant projects include;

Chester and Durham St. $1.1M

Montreal Street $1.1M

Richardson Terrace $893K

Crammer Square Lift Stn $245K

PS7 Phase 2 & 3  Shirley $2.4M

 

PERFORMANCE

Environment

Complied with SCIRT, Environment Canterbury and Christchurch Council requirement at all times for sediment control and methodology.

Health and Safety

SCIRT’s very high safety standards complied with without any significant incidents.

Programme

Achieved where works were not interrupted by extreme ground conditions, underground impediments.

Cost/Budget

Measure and value, approved variations.

DEEP SEWER AND WATERMAIN REPAIRS

August, 2014

SCOPE

Waimakariri communities were significantly affected by the earthquake and aftershocks that struck Canterbury in September 2010. This contract involved the reinstatement of infrastructure throughout the Kaiapoi District, replacing damaged sewers, sewer laterals, water reticulation and land restoration. Work was scheduled to meet separable portions at;

  • Raven Quay Sewer Repairs
  • Raven Quay and Hilton Street Water Repairs
  • Chapman Place Sewer Repairs
  • Holland Drive Sewer Repairs
  • Ohoka Road, Williams Street Kaikanui Sewer Repairs
  • Mary Ellen Pegasus PS Sewer Repairs

PERFORMANCE

Environment

Achieved compliance to Council and Environmental Canterbury environmental requirements. Traffic Management plans in place to reduce impact of works on traffic and pedestrian flows.

Health and Safety

Nil incidents

Programme

Separable portion programme prepared by Dormer Construction accepted by Council – achieved project milestones.

Cost/Budget

Value and measure. Worked collaboratively to identify opportunities to minimise cost.