World Wetlands Day 2008 shows that it is possible to achieve more sustainable agricultural and urban water practices
with an accompanying improved water quality.
WWD 2008 was celebrated on Saturday 2 February in the Waikato by almost 150 people, visiting seven separate wetland
sites on a guided bus tour coordinated by Fish & Game NZ, the National Wetlands Trust, Department of Conservation, NZ Landcare Trust and Mighty River Power. 2008 is
also the year in which the Ministry of the Environment publishes the second edition of its highly-acclaimed 1997 “The
State of New Zealand’s Environment Report”.
So 10 years down the track how far have we come in managing our environment? The WWD evidence suggest ‘a great deal’.
The 1990s was a ‘black hole’ for wetland conservation. There were no national management guidelines, the first Regional
Plans had only just appeared – and because the District Plans had been prepared before them, there was little or no
linking between their statutes regarding wetlands. Wetlands continued to degenerate and disappear. It was a very
frustrating time.
On the recent WWD fieldtrip, progress over the last 10 years, both on the ground and in attitudes, was obvious. DairyNZ,
for instance, has a demonstration of how best to minimise nutrient and sediment runoff into streams/lakes, by varying
the distance of the fence according to the slope of the paddock and using appropriate plantings in the riparian strip
between the fence and the stream/lake. Fonterra/Hautapu has a mature riparian planting (largely done by local schools a
few years ago), as well as two other experimental structures designed to reduce nutrient runoff from intensive dairying
pasture. One of these is a ‘constructed’ wetland, designed to further purify effluent from dairyshed oxidation ponds.
Over the past 15 years, NIWA’s Chris Tanner has developed ‘constructed wetlands’ into a must-have add-on to dairyshed
and rural domestic effluent primary treatment systems. Fonterra has also recently signed the ‘Clean Streams Accord”,
which promoted stream-fencing among it’s members and Environment Waikato is also moving from ‘voluntary compliance’ to
‘statutory compliance’.
Cambridge’s own urban Lake Te Ko Utu has all of the problems of Hamilton’s Lake Rotoroa, but the Waipa District Councils
management problems have been greater. Before cleaning up a lake, you need first to control the source of the pollution.
WDC has now transferred septic tank systems above the lake to the reticulated sewerage system, installed sediment traps
and brought in greater controls over stormwater inputs. Stormwater is still needed to maintain the lake, though, because
spring-inflows have diminished as the town has sealed off the ground with concrete and tarmac. The lake still has too
many nutrients, too many ducks (which also bring in nutrients), too little summer water, etc, but $600 000 has been
allocated for management improvements this year.
A delightful stop (try their organic blueberry icecream/wine/jam!) at Monavale Blueberries – New Zealand’s largest
organic blueberry farm on the deep peat deposits of Moanatuatua Bog showed that if the natural vegetation of a bog has
already been removed, the best crop to plant there is the acid- tolerant bog plant blueberry! Because it is tolerant of
high water levels and doesn’t like high nutrient levels, the peat is better conserved – it doesn’t shrink (oxidise) so
quickly. Fertiliser and pesticide sprays would threaten the Monavale organic licence, but already there is an agreement
with one neighbouring pastoral farmer (Wallace Farms)who has erected a wind-sock, so that contractors will not apply
chemicals when the wind is blowing towards Monavale. Recognition of you’re neighbour’s needs is an important aspect of
sharing a delicate soil resource such as peat and other landowners should take note. It is a pity that District and
Regional Councils didn’t take note in the 1990s, when their Plans were distinctly user-unfriendly towards wetland
resource conservers.
Now Monavale blueberry farm is no longer a wetland, although it used to be before drainage for agriculture many years
ago, but the NZ National Wetland Trust is still keen to support such enterprises, because they apply ‘wise use
principles’ to conserving peat soils, which were deposited in wetlands over the past 10 000years. Of course, conserving
the peat better than your neighbour creates problems for the future, because your land becomes an island – higher than
surrounding farmland – an water then drains out of your land into your neighbours’. There is no better illustration of
this than the 120ha Moanatuatua Scientific Peatland Reserve – only 2km from Monavale. Here, most of the Reserve’s native
species have disappeared, because the Reserve has been dried out by subsiding farmland. However, belated (after the
1980/90s ‘dark ages’ when most of the damage was done), Environment Waikato is now coming to the rescue, with Regional
Plan rules which prohibit deepening of drains within 200m of a listed wetland, without a resource consent. It’s too late
to save Moanatuatua Reserve without an expensive restoiration programme, but still, better late than never.These same
principles apply even more strongly to peat soils adjacent to important conservation wetlands.
The same ‘wise use principles’ that Monavale demonstrates also come into play at Lake Rotopiko (Serpentine). Serpentine
is a ‘peat lake’ – a very special type of lake, because it is rare both nationally and internationally. Peat lakes are
characterised by a ‘wall’ of peat holding back the water on at least one side. So if the peat goes (like agricultural
shrinkage), the lake disappears too. All peat lakes have declined in depth by at least 3metres due to drainage
operations over the years – some of them, more than that. Most are now very shallow, and that makes them very difficult
to manage for their conservation values, because they are turbid with erosion from surrounding land, high in
agricultural nutrient ts and they heat up quickly in summer. Serious attempts are now being made to reverse their
deterioration, with the major players being the Department of Conservation, Environment Waikato and the Waipa District
Council.
After very half-hearted attempts at improvement of the Lake Serpentine Reserve in the late eighties and early 90s, the
Department of Conservation and the Waipa District Council have now made the Serpentine Lake complex their ‘priority
conservation wetland’. Extensive plantings, pest fish removal and weed control, together with Environment Waikato
installing a weir so that the outlet can no longer be lowered to satisfy neighbouring agricultural interests. In fact,
EW is setting water levels for all of the significant peat lakes of the Waikato. Serpentine is now becoming a valuable
conservation and recreation resource. DoC, WDC and EW have a ‘hit’list’ of the ‘top five peat lakes and they’ll be
applying resources as they can to improve the conservation quality of them all as soon as they can.
Lake Cameron (Kareotahi) was being written off in the early 90s – heading for oblivion. Then came the Lake Cameron Care
Group in 1997 and a transformation, involving removal of willows and other weeds, setting of the lake outlet level, less
intensive land-use in the catchment and development of the area as an attractive recreational resource. John Pretty and
Alec Bennet from the local Fish & Game Cub spoke here on behalf of the Care Group, and one cannot emphasise more strongly the importance of engaging and
involving the local people if a conservation objective is to be achieved and on-going management seriously contemplated.
The existence of a local Care Group does not necessarily guarantee long-term sustainability of the resource, but in many
(most?) cases it would be difficult to achieve this objective without community support and assistance. There is a
rapidly increasing number of organised community groups making significant conservation impacts. Tune into the Waikato
Biodiversity Forum website for appreciation of the diversity of these groups.
Horseshoe Lake (Waiwhakareke) on Baverstock Road is probably the most ambitious wetland restoration project in the
Hamilton region. It is administered by the Hamilton City Council, with Waikato Univerity, Wintec, Ngaa Mana Toopu o
Kirikiriroa and Tui 2000 partners. Already there has been extensive planting, and more planting will ensure that the
wetland becomes self-sustaining. The site will be integrated with Hamilton Zoo, just at the top of the catchment, and a
cycleway, community parks, boardwalks and hides, viewing platforms and interpretation boards are in the long-term plans,
as also is a predator-proof fence. Partnership projects like this are also becoming the future of successful
conservation.
The ‘Lake of abundant food’ (Lake Otamanui) has never looked less likely to fulfil that promise! It lies at the bottom
of a gulley system originating in the township of Te Kowhai (named after the iconic golden-flowered tree, now sadly rare
there), and historically fed by water from a catchment to the south. Green Ribbon and NZ Order of Merit awards recipient
Graham McBride described the sad plight of Otamanui today. It is to some extent a tale of community and administrative
neglect and disinterest. It is not currently a pretty sight but, in a restored state, it would be the only remaining
example of a wetland of its type in the Waikato – a gulley-fed lake impounded by an ancient Waikato River gravel bar and
subject to deep flooding from the Waipa River, only 100m to the north.
So, the take-home message from Lake Otamanui is that decades of careless effluent disposal, intense peri-urban and
agricultural development, loss of its summer water supply and some poor local government planning decisions (including
failure to recognise an existing esplanade reserve and lack of protection for a pa site and pre-European fortifications)
are indications that, although great strides have been made in wetland protection during the past 10 years, since the
1997 State of New Zealand’s Environment Report, there is still a long way to go before we can say that there is a fair
balance beween conservation and development, before we can fully acknowledge that making money is not always more
important than retaining some of our natural environment for biodiversity, enjoyment and recreation, before common sense
and scientific facts take precedence over planning rules and, occasionally, personal gain. Wetlands are different from
other conservation areas like forests, because they are part of their catchment and their health therefore depends upon
what else happens in their catchments (like nutrients and erosion, for instance). We’ve come a long way, but we’re not
there yet, because compromise doesn’t always work for wetlands.
February 2nd gave 150 participants a really broad appreciation of wetlands values and the conflicting issues in their
management. What better way to illustrate the issues discussed in the new State of the Environment report?
Ends