Carterton Mayor Greg Lang wearing a cap and goggles, with council chief executive Geoff Hamilton. The new wastewater reservoir is being filled with groundwater. PHOTO/SUPPLIED
Carterton District Council [CDC] has battled significant challenges in its wastewater treatment ponds project over the past few years.
And while there may not be any silver linings resulting from reservoir lining damage and delays, the council has celebrated a project milestone – filling one of the three new ponds [Reservoir 1] with groundwater.
CDC took possession of the Dalefield site from contractor Central Hawke’s Bay Earthmovers [CHBE] in September after repeated delays and the discovery of extensive damage to the reservoir linings.
It was made known that 122 notices were issued to CHBE throughout the earthworks contract, with the latter of these to fix the damage and alter work practices that could avoid further damage.
But proposed mediation plans were considered insufficient.
The council commissioned an independent engineer’s report on the best way to repair the damaged liners, which was discussed at an infrastructure and services committee meeting.
CDC chief executive Geoff Hamilton said reaching the stage of filling Reservoir 1 with groundwater was “a testament to the tenacity and hard work of our project team and their ability to overcome hurdles and manage complex problems”.
“The engineering report provided necessary guidance for our project team,” he said.
“The project team started work on the repairs as soon as practicable to get ahead of the winter weather.
“It is hugely positive that we have got water flowing into the reservoirs now.”
The capacity of Reservoir 1 is about 60,000 cubic metres, roughly the same size as the existing three storage ponds.
The project team is using a staged approach when filling the reservoirs to ensure the safety of the team working on site, and to protect the surrounding environment.
The filling is weather dependent, with cold mornings needed to ensure the liner does not expand or crease during this crucial initial fill.
Maintaining groundwater levels below the rising level of the reservoir is also important to ensure the liner settles on to the base and slope of the structure while allowing air pockets to vent naturally.
“Filling the ponds is another huge step towards achieving our strategic goal of protecting our waterways and finalising one of our council’s largest infrastructure projects,” Hamilton said.
Planning the repairs for Reservoirs 2 and 3 is under way, with the weather and cooler temperatures potentially adding risks to the repair timetable.
The work will fall within the previously announced budget of up to $1.944 million, which was approved last December by the council. — NZLDR
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