The Tākaka Freshwater Management Unit has an area of 1013km2 and includes the Tākaka River and its tributaries, the Cobb reservoir, and all catchments between Wainui Bay and Tukurua. Three aquifers exist in this FMU: the Tākaka Unconfined Gravel Aquifer that provides Tākaka township and parts of the Tākaka Valley with water; the Tākaka Limestone Aquifer; and the Wharepapa/Arthur Marble Aquifer that feeds Te Waikoropupū Springs.
Much of the FMU is rugged and mountainous and covered in Department of Conservation-owned national forest. The lower parts of the FMU flatten out towards the main township, Tākaka, and this land is predominantly used for dairying and other farming. The geology is diverse and complex, including many rock types, significant marble layers, and the distinct Karst landscape. This leads to a complex system of aquifers, and interactions with the rivers that flow over them.
The rivers and streams of the FMU overall have good water quality and ecosystem health, but there is significant variation, with examples of the best and worst water quality in the district. This includes exceptional water clarity and ecological diversity in some water bodies, including the internationally renowned Waikoropupū Springs. Poor water quality is predominantly found on smaller, lowland streams within rural catchments, which has also negatively affected coastal water quality and swimming spots.
There is generally good water availability in the FMU with the exception of very dry times, when water takes may not be possible such as on parts of the Tākaka River and tributaries that flow into the Takaka River that are underlain by karst geology that go dry, resulting in security of supply issues. A number of catchment areas are fully allocated (particularly to the east of the Tākaka River from Pōhara up to Wainui), while the Tākaka River and its major tributaries (Waingaro and Anatoki) and northern catchments generally have some additional capacity while still meeting minimum ecological flows.
Note: text in italics shows the sections of the vision specific to this FMU.
It is 2100, our waterbodies are healthy, connected and resilient where indigenous ecosystems and biodiversity are thriving, providing
abundant mahinga kai, food and resource gathering and fishing. All waterbodies and their margins have high natural character and have room to move and adapt.
It is 2035, our land and freshwater management provides for our community’s social, economic and cultural wellbeing. People have
access to safe, clean water for drinking, swimming, recreation and cultural uses.
It is 2040, sustainable and integrated land and water management practices protect the ecosystem health and natural character of our aquifers, rivers, lakes, springs, tomo, karst sinkholes and wetlands, and provides for our agriculture, tourism, commercial and industry sectors. Our urban development connects us to our backyard waterbodies.
It is 2055, our communities and livelihoods are resilient to our changing climate, floods and droughts. We have enabled use of
renewable energy and water storage and our food producing areas continue to play an important role for local food security.
We all respect and take responsibility for freshwater health. We value the taonga we are protecting. Through collaboration and
innovation we have adapted to new ways of doing things. We have restored, protected and maintained freshwater habitats and the
quality and quantity of freshwater, enabling sustainable use for generations to come.
Te Waikoropupū Springs is Te Puna Waiora (purest water). Lake Killarney has been restored and our tamariki enjoy swimming there. The shady banks of Te Kakau and Motupipi streams provide a restful haven that protects water quality.
The Wharepapa Arthur Marble Aquifer and Te Waikoropupū Springs are outstanding water bodies with protected tikanga Māori, amenity, intrinsic, cultural health, habitat, biodiversity, wild, scenic, natural, scientific, ecological and spiritual values.
Our Tākaka Township drinking water from the ground is so clean we don’t need to treat it.
Note: Values in italics are relevant to the Water Conservation Order.
| Value Type | Values applying in FMU | Values not applying in FMU |
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Compulsory National Values |
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Other National Values |
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Other Community Values |
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Key challenges:
The area experiences a generally mild climate with average to high sunshine hours. Local climate is affected by elevation which also affects temperatures and rainfall. For example, the rainfall gradient declines from the west where it can be 5000mm/year in the western ranges, 3,500mm/year at Canaan on the Tākaka Hill, 2000mm/year at Kotinga, and to the east where it can be 1200mm/year. However, summer drought is a feature. Although, heavy rainfall is possible, causing flooding of the lower Tākaka valley and slope instability in the mountains, hills and river valleys.
The Tākaka FMU is geologically diverse and unique. It includes New Zealand’s oldest fossil-bearing rocks (early Cambrian limestone) through to the youngest riparian and coastal sand. Volcanic (basalt, andesite and ultramafic, including asbestos) and metamorphic rocks (schists, granite, marble, including Arthur Marble) are associated with the sedimentary layers. Tertiary sediments include the Tarakohe Mudstone, Tākaka Limestone and Motupipi Coal Measures. Much of the Tākaka valley floor is covered by gravels.
A distinctive feature of this area is the karst landscape. This is largely shaped by the dissolving action of water on carbonate rock in this area occurring over many thousands of years. It results in the unusual surface and subsurface features ranging from sinkholes, vertical shafts, disappearing streams and springs to complex underground drainage systems and caves.
A key geological feature influencing subsurface water, the Arthur Marble, covers an area of about 180 km2 including underneath the Tākaka Valley floor, and from Upper Takaka to the Golden Bay coast, and in the mountain ranges parallel to the Tākaka Valley section. Under the central Tākaka Valley floor the marble is covered by tens of metres of alluvial gravel and in the lower Tākaka catchment it is additionally covered by impervious Tertiary formations - i.e. the Motupipi Coal measures and Tarakohe Mudstone. The thickness of the marble is variable and is considered to be at least 500 m and possibly 1000m.
There is a small section of Separation Point granite along the Pōhara to Tata Beach hills.
The diversity of the geology leads to a soil chemistry and structure that is equally diverse. The range of soil types on the Tākaka plains range from high to low fertility, with the Rameka and Motupipi soils having high fertility. Most of the soils are deep and well drained, with the exception of the Rototai soils which occur on gently sloping land in the Rototai and Motupipi areas and are imperfectly drained. Tarakohe soils sit above the Tarakohe Limestone Formation. Intensive or extensive use of Tarakohe soils is restricted by the highly variable surface topography and proportion of rock outcrop that covers the landscape.
Tākaka is the largest catchment in the FMU with an area of 940km2. It includes the Tākaka River and its tributaries, along with the smaller catchments around Wainui, Pohara and Motupipi.
The alpine headwaters of the Tākaka River are located on the north side of the Arthur Ranges at the southern end of the FMU. The upper reaches of the river flow through national park beech forest at a mean annual flow of around 31,000 l/s (measured at Harwoods). The river then flows northwards through a narrow valley where it begins to lose water through the alluvial gravels of the floodplain into the cavernous marble beneath, with the mean annual flow of the river dropping to 14,333 l/s at Kotinga. Sections of the river can be dry in summer below Lindsays Bridge (between several days to several weeks per year), depending on riverflow, rainfall and Cobb Hydro power generation and lake storage. Parts of the lower reaches of the river channel have been straightened and modified, in part to provide flood protection.
Major tributaries of the Tākaka River include the Cobb River (and Cobb Dam), Waingaro, Anatoki and Waikoropupū rivers. These rivers and several smaller creeks all link in the lower valley creating a distinct flood plain. A feature of these smaller lowland creeks is that many are dry for most of the year. Examples include Dry Creek, Gorge Creek, Rameka Creek and Craigieburn Creeks. The Waingaro is the second largest river in the catchment, and flows east from the Lockett Range, before joining the Tākaka River near Paines Ford. The Anatoki River descends very steeply from a similarly mountainous area to the west of the Tākaka River, before joining it near the Tākaka township. Toward the lower reaches of the catchment the Waikoropupū River meets the Tākaka River. A substantial amount of water flowing into the Waikoropupū River is from the Te Waikoropupū Springs via Springs River.
The Motupipi River to the east of the Tākaka River is mainly a spring fed lowland stream and flows to the Motupipi estuary. The Wainui River, the easternmost catchment in the FMU, flows from Mount Evans through a narrow gorge in the Abel Tasman National Park and out to Wainui Bay.
The much smaller Tākaka north catchments have a combined area of 73km2 and include the Onahau, Puremahaia, Pariwhakaoho, Onekaka and Tukurua Rivers. Areas to the east of the State Highway where the rivers originate, rise steeply and are largely within the Kahurangi National Park. Aggradational terraces form the flat land immediately adjacent to the State Highway and towards the coast.
Around 70% of wetlands/swamp areas have been removed from lowland and low hill country of the Takaka FMU since about 1840. Almost all the wetlands that remain are located in in high country areas. The major areas of lowland wetlands remaining include the Onehau Wetland and Little Onehau River catchments (mostly pakihi), near Waikoropupū, and Tukurua Rivers.
The largest lake in the FMU is the Cobb Reservoir, completed in 1956 to provide water for hydro-electricity. There are over 15 alpine lakes in the upper catchment including: Lake Stanley (formed by landslide in 1929), Lockett, Sylvester, Iron, Cobb, and Diamond. Almost all lowland lakes in the FMU are sinkhole lakes, including Lake Rototai/Blue Lake. Lake Killarney in the Tākaka township and several small lakes near the upper southwestern end of Long Plain Road are some of the few lakes heavily polluted with nutrients.
Te Waikoropupū Springs is a large karst resurgence consisting of a main spring and a number of smaller springs. Te Waikoropupū Springs are the largest in the Southern Hemisphere and are an example of a wetland type that is rare in New Zealand and of immense cultural significance to local manawhenua. They are also an important tourist attraction for Golden Bay. In recent years, however the nitrate levels at the springs have been detected as increasing.
There are three main aquifers in the FMU - the Arthur Marble Aquifer, Tākaka Limestone Aquifer and the Tākaka Unconfined Gravel Aquifer. These are directly related to the underlying rock characteristics and geology. There are complex interactions and connections between the various aquifers and the rivers and streams in the area including their recharge and discharge, and their nature i.e. unconfined and confined.
The Arthur Marble Aquifer (AMA) is the principal aquifer in the Tākaka Valley. It is held within the Arthur Marble due to its karstification (the process of rocks being eroded by underground water to form features such as sinkholes and caves) and in some places such as East Tākaka and Te Waikoropupū Springs area, it is more than 500 metres deep. The AMA covers an extensive area of 86.6km2 and has a water volume of 3.4 km3. Water in the aquifer has an estimated residence time between 1.2 to 10.2 years. Recharge is from rainfall as well as flow from the main rivers. For example, the Tākaka River loses on average 8000 l/s into the aquifer below Lindsays Bridge.
The AMA is unconfined from Upper Takaka to about Hamama. North of Hamama the AMA becomes confined by impervious Motupipi Coal Measures that overlie the Arthur Marble. Te Waikoropupū Springs are the main discharge zone for the AMA, along with the coastal marine area of Golden Bay. The Tākaka Limestone Aquifer (TLA) occurs between East Takaka and Tarakohe and has a thickness between 30 – 60m. The Takaka Unconfined Gravel Aquifer (TUGA) covers most of the Tākaka Valley from Upper Tākaka to the sea with a depth of between 5 and 60m thick.
The receiving environments for discharges from these freshwater bodies include:
The Tākaka Valley was originally densely covered in tall forest, mostly totara, kahikatea or beech. Northern rata occupied coastal and lower limestone areas. Towards the coast open flax and cabbage tree swamp was common with estuaries and sand spits a feature of the river mouths and coastline. The wetter terraces carried pakihi shrubland and forest with rimu and silver pine. Above the natural bushline a mix of shrubs, snow tussocks and herbaceous plants occurred.
The Tākaka catchments, particularly the coastal areas, were used extensively for cultivation and habitation by Māori, due to the rich mahinga kai, mahinga mātaitai and other special resource areas found there.
During the late 19th Century, virtually all the forest in the valley was cleared for farming and timber used for building and shipping. Along with vegetation clearance the wetlands were drained. Less than 1% of the original swamp forest now remains. Only about 25-30% of freshwater wetlands remain.
Today, close to 80% of the FMU (785km2), particularly in the mountainous areas remains in native forest predominantly within the Kahurangi National Park and Tākaka Hill Forest Park. Exotic grasslands cover most of the remainder of the FMU (15%). Dairying is the predominant land use on much of the flat land in the valley floors and Tākaka North catchments. There are also areas of sheep and beef, deer, and horticulture, including kiwi fruit, and limited areas of pine forest (2%).
Tākaka Township with a population of around 1400 is the largest settlement in the FMU and lies on the floodplain in the lower reaches of the valley. Smaller settlements occur in Upper and Central Tākaka, Clifton, Pōhara, Ligar Bay and Tata Beach along with rural-residential or ‘lifestyle block’ land use around these areas. The Tākaka North catchment, contains several small beach communities, such as Patons Rock and Tukurua.
Some 19 of the 51 freshwater fish species are found in the Takaka FMU. While some parts of the FMU have very low fish diversity such as streams that go dry for much of the year in the Takaka Valley (e.g. Dry, Rameka, Gorge, Waitui (mid and upper reaches only), Craigieburn, Stony), the very high native fish diversity in lowland streams near the coast. In some streams we have found the highest fish diversity in one reach in the whole of Aotearoa e.g. Onekaka. These coastal streams with high diversity of fish species include: the Tukurua, Onekaka, Parawhakaoho, Onahau (little and big) and streams in Wainui Bay,). Giant kokopu is particularly abundant in wetland-fed streams such as Dogan Creek (Onekaka catchment) and tributaries of Waikoropupu River. Dwarf galaxias have recently been found in the Waikoropupu catchment. Kakahi/freshwater mussels are found in the Motupipi catchment.
There are barriers to fish access on some streams, including culverts. The macroinvertebrate community on the Onekaka River is diverse (Macroinvertebrate Community Index 115-130) and is dominated by mayflies, stoneflies and caddisflies.
Although fish diversity is good in many lowland streams, there are still quite a few that have been straightened and lack native tree cover and are therefore very compromised.
In comparison there is relatively low species diversity in the upper Tākaka especially in and above the drying reaches. The Cobb Dam restricts migration of longfin eels and koara, and upland streams and rivers are too far for migratory fish species. However, the Waitui River for example had very high macroinvertebrates when surveyed in 2010.
The Waikoropupū Springs supports a diverse aquatic flora and fauna. This includes 16 species of algae, seven species of moss, three species of liverworts and two species of angiosperms some of which are nationally unique. Ten species of worms, six species of crustacea, two mites, 28 species of insects, three snails and four fish have been recorded from the springs.
Examples of all original native flora are present in the FMU, with the exception of some local extinctions since human occupation such as pakihi podocarps, maire and pingao. Manawhenua ki Mohua have identified 100 plant species and 60 bird species that are taonga in the FMU. Significant areas of native habitat are present given the large area of the FMU within conservation estate. However, there is little native habitat on land below 500 metres and there have been many extinctions and species decline, especially among birds.
The most significant coastal bird site in this FMU are the “internationally important” shellbanks at Rototai, near the Motupipi River mouth. These have been found to support a significant proportion of the breeding populations of Black-billed Gulls / Tarāpuka, Red-billed Gulls / Tarāpunga, Caspian Terns / Taranui and White-fronted Terns / Tara.
The invertebrate fauna of Tākaka is renowned for two reasons: the several species of large landsnail, Powelliphanta, and the limestone cave fauna. Landsnails are being severely impacted by predation from wild pigs. New Zealand’s unique and largest, rare cave spider (Spelungula cavernicola) is found only from limestone caves in Tākaka and Oparara. Manawhenua ki Mohua have identified 45 invertebrate species that are taonga in the FMU.
Tasman District Council with ESR have been undertaking GDE assessment specifically for stygofauna in the Tākaka FMU which includes the AMA and TUGA since 2018. The ESR 2021 report indicated total abundance and species richness were low, compared to ecosystems examined in other South Island locations. The 2020 sampling seasons results indicate an endemic ecosystem is present. While stygofauna at the period of sampling did not appear to be abundant but more species could be discovered with more sampling. The karst system in Tākaka itself is unique in its evolution and geochemistry and a system that evolves with karst dissolution.
The Takaka FMU is host to a number of ecologically important estuaries including: Wainui, Tata, Motupipi, Waitapu-Takaka Delta, Onahau and Onekaka. As an example, the Motupipi Estuary is a moderate-sized (169ha), shallow, well-flushed, seawater-dominated, tidal lagoon type estuary with one tidal opening, and two main basins. Ecologically, habitat diversity is moderate to high with much of its intertidal vegetation intact, extensive shellfish beds, large areas of saltmarsh (39% of estuary), and some seagrass (1.6% of estuary). However, the estuary is excessively muddy (22% soft mud) and the natural vegetated margin has been lost and developed for grazing. Also, since 1943 there has been a loss of 24ha of saltmarsh through drainage and reclamation.
Key water quality characteristics for the FMU are summarised below:
Some water quality issues that need addressing include:
Residents of the Tākaka township obtain water from private individual domestic bores that are generally between 5 - 8 m deep. These bores are mainly driven pipes as groundwater is easily accessed by surface pumps. The water table is not far below ground level (2 - 3 m) and within easy suction reach for the surface pumps. The groundwater is unconfined.
The Water Conservation Order recently gazetted only allows for further irrigation in the recharge area if set limits for nitrates are met at the Te Waikoropupū Springs. The limits set in the order are lower than the current measured levels and hence any new irrigation that can add nitrate to the system cannot be consented.
For many catchments in Tākaka, water supply is reliable most of the time, but during infrequent particularly dry times, water may not be able to be taken for extended periods at a time. Those reliant on a high supply security may need to install water storage, find alternative supplies or change management practices in these situations.
Recent analysis by the Tākaka Freshwater and Land Advisory Group to define appropriate allocation limits, has found that all zones with the exception of Tukurua are currently either under or fully allocated. Additional water up to the proposed allocation limit is available at varying degrees in the following zones: Waingaro, Upper Tākaka, Lower Arthur Marble Aquifer, Anatoki, Tākaka township, Motupipi surface water, some streams and groundwater in the coastal western catchments, Campbell Creek, and Wainui.
Water is generally fully allocated in the Pohara, Ligar Bay, Wainui North and Rototai catchments.
In the Tukurua Zone, the current amount of water allocated in consents is slightly higher than the proposed allocation limit although this is because non-consumptive water is included in the cumulative take.
FLAG Recommendations Report - July 2019.pdf (pdf 2.8 MB)
Matauranga Report - June 2019.pdf (pdf 3.4 MB)
Water Resources of the Takaka Water Management Area.pdf (pdf 19 MB)
Opportunities for ecological restoration report
2005_Soils of Lower Takaka Valley.pdf (pdf 880 KB)
Naturally uncommon ecosystems - pakihi wetlands
State of the Environment Report 2011 - Freshwater Fish.pdf (pdf 6.8 MB)
The health of freshwater fish communities in Tasman District 2018.pdf (pdf 9.9 MB)
Coastal Risk Assessment Monitoring Report August 2012.pdf (pdf 6.5 MB)
Review of current and past health of Ten Tasman Lakes 2023.pdf (pdf 4 MB)
