The Catchment
The Piako catchment is a unique and diverse landscape, home to globally significant wetlands, remnant forests, and a rich variety of native wildlife. Despite its history of intensive land use, the catchment offers abundant opportunities to restore and celebrate its natural treasures for generations to come.
Wild Piako / Home to globally significant wetlands and remnant forests
The Piako Waihou catchment is a unique and diverse landscape, home to globally significant wetlands, remnant forests, and a rich variety of native wildlife. The Kopuatai Peat Dome is a world-class wetland, and the catchment feeds into the internationally important shore-bird feeding grounds of the Firth of Thames, making the health of our waterways a matter of both local and global significance.
Historically, the floodplain forests of the Hauraki Plains supported huge flocks of kererū and kaka when kahikatea trees fruited. Today, remnants of these ancestral forests remain, providing a rare opportunity to restore an almost lost ecosystem. The hills surrounding the catchment—Pukemokemoke, Maungakawa, and Te Miro—contain extensive native forests, and community members work hard to protect these areas from pest plants and animals.
The catchment is home to a variety of native wildlife. Iconic birds like tui are increasing in number, while kaka are frequent visitors in winter. The native long-tailed bat also uses remnant forests along waterways as corridors through the landscape. These natural treasures highlight the importance of working together to preserve and enhance the Piako’s biodiversity, ensuring it remains a source of pride for our community.
Catchment / StoryMap
Our Story Map is a strategic communication and planning tool designed to showcase the big picture and highlight contributions to a catchment-wide vision.
Key Elements:
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Provides essential understanding of where projects are
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Information sharing, storytelling, and collaborative approaches
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Helps identify which actions will have the greatest impact and where they should be implemented
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Functions as a catchment-wide tool that's relevant and accessible to all stakeholders
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Funding - Phase 1 development is funded by A2E (MfE)
Explore the Piako-Waihou Catchment Insights app
The map shows the Piako and Waihou catchments. You can search for your address or navigate and zoom into your preferred area to explore a more detailed network of waterways.
The catchment encompasses six district councils within its boundary:
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Matamata-Piako
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Hauraki
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Thames Coromandel
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South Waikato
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Waikato and Waipa.
Water Quality / Restoring River Health
The Piako River is the dominant waterway in the Matamata-Piako District, flowing approximately 100 km from the Te Miro-Tahuroa hills and Pakaroa Range to the Firth of Thames, passing through Morrinsville and Ngatea. Its catchment includes two major stems—the Piako River and the Waitoa River—fed by numerous smaller streams and wetlands. Together, these rivers drain much of the Hauraki Plains and contribute around 25% of the water flowing into the Firth of Thames.
Intensive agriculture has historically impacted water quality, although monitoring shows some improvement in recent years. The Waikato Regional Council collects data on water quality and aquatic ecosystems at multiple sites. Water quality ranges from poor to excellent, with headwaters surrounded by native vegetation generally in the best condition. Total phosphorus and nitrogen are improving at most sites, while E. coli and turbidity remain areas of concern. Ecological monitoring of invertebrates also provides insight into river health, showing variation across the catchment.
The Piako River and its tributaries support a variety of freshwater species, with 21 recorded species including 14 natives such as longfin and shortfin eels, kokopu, and several bully species. The black mudfish, a resilient native species, has historically thrived here. Exotic species, including gambusia, goldfish, and bullhead catfish, are present in the lower reaches and drainage canals, often impacting native fish populations.
Geology / Maps and soil composition
The Piako catchment sits within the Hauraki Rift and has been shaped by dramatic geological events. Sediments from the Taupō volcanic zone and historic Waikato River flows have created deep, fertile soils across the plains. Widespread peat formation, particularly at the Kopuatai Peat Dome, reflects poor drainage in low-lying areas.
Soil types vary across the catchment, from clay and loam to peaty soils, supporting both productive farmland and natural habitats. Groundwater flow contributes significantly to river discharge, particularly during dry periods, helping maintain the Piako’s connection to the Firth of Thames.
