Hahei Drinking Water Upgrade – 2022 Update

Bore and Pipeline Development

Two bores have been drilled, constructed and tested. Production Bore 1 (PB1) is constructed to a depth of c. 135m and is on the western side of Hahei Beach Road at the top of ‘Snake Gully’. Production Bore 2 {PB2) is constructed to a depth of c.150m and is on the eastern side of the road, at the bottom of Snake Gully.  At each site, an observation bore was installed to enable monitoring of the groundwater response during the pumping test.

Water quality samples were collected and analyzed.  Results indicate good water quality without elevated metals.

Pumping tests were undertaken at each production bore in accordance with Regional Council consent requirements. Each pumping test occurred over one week which included days of pumping followed by a period of groundwater recovery. Groundwater levels were measured in the production bores, observation bores, two neighbouring private bores during both tests.

The pumping test data is currently being assessed and a report is being drafted. The test results will enable an understanding of the aquifer parameters (how the groundwater responds to pumping the production bore), the sustainable yield of the bores and qualification of the effects of pumping on other bores and surface water (if relevant). Once the report has been received Council will need to consider the results and then engage with the relevant land and bore owners. Ultimately resource consent (water permit) will need to be sought from Waikato Regional Council. We anticipate that a consent application will be lodged in 2023.

Design and contract documentation is being prepared for the pipelines from the bores to the new Water Treatment Plant.  The documentation will also include a new rising main pipeline from the water treatment plant to the Grierson Close reservoir.

Water Treatment Plant Progress

The concept design of the new Water Treatment Plant (WTP) is complete and enabling works required by the geotechnical design have commenced. This involves significant pre-loading of the site that will be monitored for the period until the required improvements are achieved.

Completion of the WTP is scheduled for late 2023 but the required pre-load consolidation period is somewhat unknown, but it should not slip past the end of the 2023-24 financial year.