Urgent erosion protection work at Horokiri Stream in Battle Hill Farm Forest Park, initiated by Greater Wellington, has safeguarded the public water supply following heavy rainfall on 26 August. The downpour caused significant erosion, threatening the water treatment plant located in the park’s historic red milking shed.
Greater Wellington Park Ranger Gary Wheaton and Resource Management Advisor Rachael Boisen Round had previously identified the area as an erosion risk. However, the damage caused by August’s rainstorm required immediate action.
Mike Harkness, Senior Analyst – Hydrology at Greater Wellington, reviewed the stream’s data, stating, “it was the 7th highest flow on record since the Snodgrass monitoring site was established in 2002.” The park was temporarily closed after the stream overflowed.
Remedial work, including a fish rescue, was completed over three days. Senior Biodiversity Advisor Ashley Webby says, “longfin tuna, kōura, and bully were rescued and relocated.” Over 140 tonnes of rock were used to build protective groynes, with the structure reinforced by excavated material and 200 replanted carex grasses.
George Bowman, Team Leader of Assets & Performance, praised the collaboration involved, stating, “the success of the Horokiri Stream erosion works showcases the power of teamwork within Greater Wellington, protecting a vital public resource.”
The park is now open again, offering outdoor activities such as walking, camping, and farming education.