LakesWater Quality Society and the Restoration of the Rotorua Lakes
A community group, the LakesWater Quality Society (LWQS), successfully initiated action to restore water quality in a major group of lakes in the Rotorua district. This account is written from the perspective of the chair of the Society from 2000 to 2006. It deals with events of those years and briefly touches on the later implementation phase.
The twelve splendid Rotorua lakes are in the North Island of New Zealand.1 All were formed by volcanic events but vary in characteristics and water quality. Volcanic domes and caldera dominate the landscape. Landforms are mantled by rhyolitic ash eruptions. Rainfall trickles through the soil into pumice aquifers, and some take a century to reach a lake. Water from hydrothermal springs also enters several lakes.
Before human settlement, the land was covered by a temperate rainforest dominated by podocarps. Only limited changes were made in the vegetation by the Maori,2 who arrived around the 14th century.
Before 1880, when Rotorua town was formally established on the edge of Lake Rotorua, European settlement took place slowly.3 The town itself was largely a tourist center and managed as a ‘government town’ for many years.4 As the town of Rotorua grew, nutrients from sewage were discharged into Lake Rotorua with little treatment,5 leading to a deterioration in lake water quality.
Forests were cleared as trees were felled for timber and pine (Pinus radiata) plantations were developed in the 20th century. Farming was slow to develop since sheep and cattle did not thrive. After a deficiency of cobalt was identified in 1935,6 livestock farming spread around several lakes and eventually increased the outflows of nitrogen compounds to these lakes. Government policies to stimulate farming encouraged livestock farming in the catchments.
In 1969 a visiting American compared Lake Rotorua to an ”unflushed toilet” —to the horror of the mayor.7 A few scientists warned of the degradation of the lake water.8 Eventually public pressure led to a proposal to divert little-treated city effluent to the Kaituna River that flows out from Lake Rotoiti (and hence drains Lake Rotorua as well). But a local Maori leader objected and won a legal claim against the government.9
Rotorua City had a population of over 50,000 in 1991 and by then was building a modern sewage treatment plant to remove most nutrients.4,10 The local government authorities and the community relaxed: it appeared that Lake Rotorua was saved.11 Little concern was shown about the other apparently less threatened lakes. In 1999 the Regional Council (BoPRC or EBOP) estimated a cost of only $3.84 million to ”protect the twelve lakes … for ecological, recreational, and cultural importance…”.11
In 2000 EBOP proposed the Regional Water and Land Plan (RWLP) which became effective in due course. This included Rule 11, which prohibited any further intensification of land use that could increase nutrient discharge to Lake Rotorua or four other lakes.
The RWLP included individual targets for water quality for the Rotorua lakes. The realistic objective was for the water quality for each lake to be maintained above, or restored to, what as it was in 1960, rather than back to pristine purity. The indicator of quality used was the Trophic Level Index (TLI).12
We, the lakeside dwellers, became concerned in the late 1990s. Cyanobacterial blooms occurred annually in a few lakes and other algae, such as waternet and foam-producing algae, came and went. Slowly, almost imperceptibly, the water in the linked lakes Rotoiti and Rotorua became murkier. Leading scientists were unconcerned. EBOP no longer monitored water quality annually in all lakes.
LakesWater Quality Society Mobilizes
A local community group called the ”Lakeweed Control Society” was struggling to survive. Founded 40 years earlier by an eminent lawyer, the Society had initiated government action to control the oxygen weed Lagarosiphon by spraying with Diquat. By 1999 the control program was well established, and the Society had achieved its original purpose.
I became chair of the committee of the Society in 1999. The Society changed its name and tackled water quality issues. The first problem we faced was limited knowledge as to what was happening in the lakes. We informally approached the National Institute of Water and Atmospheric Research (NIWA) seeking research on water quality in the Lakes. We were rebuffed. A very senior executive told us that enough was already known about the Lakes.
The LWQS committee reacted strongly. One urged action, and another advocated a scientific seminar to determine research requirements. So the first transforming symposium was initiated as a team effort.
The first symposium was held in March 2001 in Rotorua. Its theme was ‘Research Needs in the Rotorua Lakes.’ Over 100 people attended, including scientists, local government leaders and managers, local people, and executives from lakes-related industries. The infectious enthusiasm of a keynote speaker Professor Willie Ripl of Berlin University enlivened the symposium. He pointed us beyond the lakes to complete catchment systems.
That symposium had unexpected but far-reaching outcomes. The chair of EBOP asked me if I would write a letter to his council asking them to endow a chair in lake science at the University of Waikato. With alacrity I agreed, EBOP endowed the chair and a brilliant choice was made of Dr. David Hamilton as inaugural professor.
A second outcome of the symposium was the message that a farmer took home to his colleagues around Lake Rerewhakaaitu: “The water quality in Lake Rerewhakaaitu is deteriorating. It is our lake. We as farmers are causing the problem. It is up to us to fix it.”
Since then seven symposia have been held, each dealing with the current issues facing the restoration of the lakes and with up to 250 people attending each symposium.13
Lake restoration: the regulatory environment
by Hannah Mueller
The restoration of the Rotorua lakes can be linked with recent changes in freshwater management proposed by the central government of New Zealand. Until 2011, the 1991 Resource Management Act (RMA) governed management of freshwater bodies. The RMA failed to achieve their protection during rapid intensification of land use and increasing diffuse nutrient pollution. Under the RMA, activities that contribute to lake eutrophication, e.g., pastoral dairy farming, are unregulated activities. In 2011 a National Policy Statement on freshwater management was introduced and in 2013 it was followed by proposed amendments. The amended NPS would provide a first step towards a limits-based approach.
This would replace existing voluntary accords based on commitments by stakeholders in the dairy industry to reduce their negative effects on freshwater. The amended NPS is focused on limits designed from collaborative input from communities to manage water according to regional land use and community values. The allowance of long time frames and community agreement mean that changes to pressures on ecosystems will take time to effect.
The Bay of Plenty Regional Council operated ahead of the national directives by limiting nutrient outflows to some lakes (Regional Land and Water Plan, Rule 11) and later implementing its own limits-based regional policy statement. It established a voluntary stakeholder agreement to work together to target nutrient reduction in Lake Rotorua (Oturoa Agreement, 2013). For New Zealand as a country and the Rotorua lakes in particular the new regulatory environment could offer a path to greater community involvement.
Steps to a Solution
By 2000 only a few scientists maintained an interest in the Rotorua lakes. The consensus was that their problems had been fixed by treatment of urban sewage and by soil conservation measures, and that the Lakes were recovering.14,10
Professor David Hamilton was the key to re-evaluating the scientific basis for the lakes’ problems. His measurements described what was happening in the lakes, and his models enabled remedies to be tested. His students and the body of expertise created at the University of the Waikato rejuvenated lake science in New Zealand.
NIWA contributed with scientific information related to the catchments, and with the Geological and Nuclear Sciences (GNS), discovered the long lag-times between nutrients entering the soil and reaching the lakes.15 This explained why water quality in Lake Rotorua was again deteriorating after initially improving when nutrient inflows from sewage were reduced. Nitrogen inflows from the increase in farming were delayed in reaching the lake.
A Technical Advisory Group (TAG) provided valuable external scientific advice to the lakes program. Our symposia reported and publicised scientific developments, and we also provided support for postgraduate students.
Three levels of government share the responsibility for the lakes: central government, the Regional Council, and the Rotorua District Council (RDC). Each organization needed to be convinced that action was necessary. The LWQS used many channels to persuade them. We lobbied local councillors and made presentations at their meetings. We were received courteously and often invited to join in a nice lunch. Some managers patronised us offensively.
We made submissions to their annual and long term plans. Initially these submissions had no effect. We were told that the lakes were either in a satisfactory state, or if they weren’t, that eutrophication was irreversible; or that action already taken would eventually lead to better water quality. In any case, nothing could, should, or would be done. Despite the lack of response, the LWQS presented the case without rancor.
The RDC was in denial as to the need for further sewerage reticulation. The mayor said the lakes would take 200 years to fix and hence there was no urgency. His complacency was disturbed when, on arriving late at a public meeting on lake water quality degradation, he found the room so crowded that the local Member of Parliament (MP) was sitting on the floor and he himself could not get a seat.
The media, especially the NZ Herald and several TV stations, were helpful, especially after widespread algal blooms in 2002.
The LWQS engaged with the central government through the local MP and through the Ministry for the Environment (MfE) of which the chief executive, Dr. Barry Carbon, was serendipitously well qualified in environmental water sciences. He came to look at the problem for himself. He spent most of a week investigating, meeting managers and technical staff from both councils, inspecting the lakes and catchments, and listening to LWQS and other community groups. Finally he met the managers from both councils. He told them that they had a major problem, that they needed to deal with it, and that he would provide help. That moment was a turning point in the history of the Rotorua lakes.
Dr. Carbon commissioned an Australian scientist to review short-term management options for Lakes Rotorua and Rotoiti. Several major recommendations in that review were implemented,16 leading to great improvement in Lake Rotoiti and some improvement in Lake Rotorua.
Once persuaded of the need for action, EBOP moved vigorously.17 Paul Dell, as a Group General Manager, attacked the lakes’ problems with vigor and was supported by the chair of his council. The RDC responded with a sewerage extension program.
EBOP, RDC and Te Arawa (see below) had worked together to produce an important-sounding but ineffective ‘Lakes Strategy Plan’.18 The coordinating body (Rotorua Te Arawa Lakes Strategy Group) was given formal status in 2006 in legislation that transferred ownership of lakebeds back to Te Arawa,19 and has over time become effective.20
The LWQS had considerable support from the public and from other community groups including the Mourea Okawa Bay Action Committee (MOB), the Lake Rotoiti Ratepayers and Residents Association, and residents’ groups at other lakes. Owners of holiday homes around the lakes, particularly from Auckland, provided funds and support. Many local people supported our work. We found little interest among tourist operators or their organizations, despite their commercial interest in making the lakes more attractive. Few businesses in Rotorua City provided support. The city had turned its back on the lake.
Te Arawa is the Maori iwi (tribe) whose territory covers the Rotorua district. Te Arawa owns nearly all the lakebeds, and Maori trusts are major land-owners. The status of Te Arawa as tangata whenua (people of the land) is recognised by law. Te Arawa has had involvement with lakes programs since 1998.21 The LWQS has benefited from Maori representation on its committee and several Rangatira (chiefs) have given their strong support.
Dr. Carbon proposed a collaboration between LWQS and farmers to deal with lake problems. He offered government funding to set up a body: the Lakes and Land Trust. The partners were LWQS, the local Federated Farmers organisation, and a subgroup of Te Arawa. Management services were provided by the NZ Landcare Trust, an environmental NGO that worked extensively with MfE.
Despite the goodwill, the Trust never fulfilled its purpose. Not all farming leaders recognized a need to reduce nutrient outflows into Lake Rotorua. Other factors that contributed to ithe Trust’s failure were the following:
• Landcare Trust sought to copy the Taieri Model (their work in the Taieri river catchment in the South Island). But the model did not transplant well because of different institutional relationships in Rotorua.
• MfE grants required tangible outputs to trigger payment of funds, but much of the work of the Trust was not quantifiable. Artificial milestones (e.g. drafting a strategy for science) were created to release funding. These diverted work away from effective activities.
• No mediator was involved, nor was there funding to encourage farmers to reduce nutrient outflows.
The Trust remains in existence as a collective of landowners.
Central government funding was needed to assist lake restoration, but it was hard to obtain despite a benign fiscal climate. A turning point was a visit by the Prime Minister, Helen Clark. She was brought by local officials to Lake Rotoiti where she stood on the shore. A woman member of the LWQS committee took the Prime Minister by the elbow and guided her out over the lake on a narrow jetty, barely wide enough for both to stand upon. The Prime Minister’s security officers were appalled. The discussion between two feisty ladies did not take long, but the Prime Minister was persuaded that action was needed. This short walk down the jetty was eventually worth $72.2 million to the lakes in government subsidy. The local MP Hon. Steve Chadwick played a significant role in the detailed work to crystallize official support.
Remedial activities were planned in consultation with local communities through the formulation of action plans devised by Action Plan Working Groups. Draft action plans were prepared by EBOP for each lake with a scientific assessment of the lake and its catchment, and the sources of nitrogen (N) and phosphorus (P) enrichment were identified. Possible interventions were described and evaluated, and the working groups expressed community preferences. Their role was consultative, educative, and advisory.
The action plans got off to a shaky start at Lake Okareka: in part because the lakeside community was divided over the relative importance of better lake water quality as compared with pastoral vistas, and in part because of reluctance by officials to yield leadership to the community. Eventually a plan was produced and has been successfully implemented.22 Lessons were learned, and action groups and action plans were effective for some lakes.
The most difficult issue was unsolved: a reduction of the outflow of N from farm land in the Rotorua catchment as diffuse discharge.23 It was not enough that the authorities were consulted and the parties met together. The farming leaders of the time were not committed to change and no skilled facilitator was used.
Later, in 2009, EBOP froze action plans after a legal opinion cast doubt on the validity of the basis for requiring nutrient reductions from farms.24 After a delay, action groups were reinvigorated for Lakes Rotoehu and Rotoma, and similar processes involving the community were recently initiated for Lakes Tikitapu and Okataina and restarted for Lake Tarawera.
With great reluctance, we in LWQS spent much time and effort on the processes required by the Resource Management Act (RMA), which is the basis of environmental law in New Zealand.
We were involved with various consent applications under the RMA. We dealt with the Regional Water and Land Plan (RWLP) as it was being developed and especially Rule 11 of that Plan. Two issues arose:
• Farmers were concerned over restrictions on intensification of land use.
• No action was proposed to protect the seven lakes not subject to Rule 11. All these lakes had water of higher quality but were at that time not considered to be threatened. We objected to this in the proposed RWLP and eventually agreed to a compromise that required action plans should water quality fall below a threshold level. While this seemed far too soft at the time, it has proven to be valuable in getting action initiated automatically.
Under the RMA, the underlying statutory document setting limits and timeframes to reduce nutrient flows in the region is the Regional Policy Statement (RPS). Negotiations over the proposed RPS involved LWQS heavily for several years before the water quality provisions were agreed upon in 2013.
In 2006 I resigned as chair of LWQS, John Green QSM was elected and has led the Society since. His wife, Ann, has played an important role as the Society’s secretary.
The work of LWQS changed as the councils became active, and we worked with them on implementing action plans to fix the lakes. For example, we advocated low-pressure sewerage systems with ”grinder pumps” rather than gravity systems. We persuaded EBOP that 250 years was too long to wait to restore Lake Rotorua’s water quality. We continued to support scientific research and its dissemination. We continued to organise symposia focusing on the most important issue at the time, but with a broader scope. We continued to bring in world-renowned experts such as Professor Robert Costanza (by video) and Mayor Bo Frank of Växjö, Sweden.
Agreement between farmers and LWQS on reducing flows of nutrients from farm land came as a result of fresh initiatives by our MP (Hon. Todd McClay) and farming leaders. This was given legal effect in 2013 when the Environment Court approved it as part of the Regional Policy Statement (RPS). Many people, other than those mentioned here, have contributed to the success of the lakes programme.
Lake restoration: management regimes of Lake Rotorua
by Hannah Mueller
Since 2007, management of Lake Rotorua, the largest of the Rotorua lakes, has included treatment of two inflowing streams with alum in order to reduce in-lake concentrations of phosphorus and to slow and reverse eutrophication. The Trophic Level Index target for the lake, which was set at 4.2 a part of a community consultation process and is indicative of trophic status of the lake in the 1960s, was attained in 2012-13 after five years of alum dosing during which time the TLI decreased markedly. Dosing with alum is arguably the main driver of the reduction in TLI for Lake Rotorua and questions might now be raised about whether achieving this target may reduce impetus to more efficiently retain nutrients on land.
Given uncertainties about the consenting process and long-term sustainability of alum dosing, it seems imperative that the window of time for improved water quality which has been provided by alum dosing, should be used to drive down nutrient loads to levels congruent with the target TLI in the absence of alum dosing. Further efforts to reduce nutrient inputs and integrated catchment management based on sound science can provide options to sustainably restore and enhance the diverse and complex ecosystems of the Rotorua lakes.
Dosing with alum or similar chemicals has played a much lesser role in the remediation programmes for most other lakes.
[Note: this sentence seeks to sum up a quite complex set of remediation measures: with dosing heavily used at the small Okaro, used initially at Okareka but with apparently mixed results, used only in embayments at Lake Rotoiti, especially when BG outbreaks have followed heavy spraying of weeds, and not used at for Tikitapu. What I seek to avoid is the impression that the programme overall has been dominated by alum dosing.]
With all the authorities convinced, action started to save the lakes. The remediation is a story in itself, and the following is only a summary.
The developing scientific evidence confirmed that enrichment by N and P compounds from human activities caused most of the lake problems. By the early 2000s, all the easier measures had already been implemented: fencing cattle away from streams and lake margins, planting erodible banks of streams, and dealing with effluent flows from dairy-farm milking premises. The measures needed were substantial and expensive:
• reticulated sewerage for communities around the lakes,
• specific engineering works such as the ”Lake Rotoiti wall” and the precipitation of P from some lakes and streams,
• adoption of best practices in nutrient reduction by farmers, and
• some change in land use from farming to forestry.
The solutions required bigger changes: much more than minor modifications in behavior by people living in the catchments. Major investment and changes in public policy were also required.
Interventions were discussed by working groups and formally approved by the Lakes Strategy Group and by the two local authorities (RDC and EBOP) who carried out the program.
The first of the new major measures put in place were the Okawa Bay sewerage reticulation in 2006 and the ”Rotoiti Wall” in 2008.25,26 The role of RDC was provision of sewerage reticulation and treatment, which comprised about half of the total program costs. The city treatment plant was progressively upgraded to deal with increased inflows.
EBOP designed and implemented other projects, including several engineering works. It is collaborating with farmers around the lakes to reduce their nutrient outflows. EBOP has also tested weed harvesting and aeration as methods of reducing nutrient levels in lake water.27
Funding was provided by the central government, EBOP, and RDC by charging for sewerage services and through rates (local taxes). Public-sector costs were borne about 50/50 by the central government and by the two local councils. In addition, farmers will bear much of the cost of improving management or changing land use. The EBOP has always been in a strong financial position, and has used its financial strength to support the program.
The RDC was in a very different financial position with projects like the airport extension requiring funding. Nevertheless it too, once convinced, gave priority to funding sewerage works to benefit the lakes.
The central government funding came in two parts: $7.2 million committed in 2004 as a result of Dr. Carbon’s initiative, and then $72.1 million committed in 2007. The latter was negotiated with ministers by EBOP and RDC with LWQS assistance.
Water quality in the lakes is generally improving.28 By the 2012-2013 season, the TLIs were falling for most lakes where interventions had been carried out.29 It is far too soon to claim victory since climatic fluctuations may be a factor, but the results and actions taken are tangible. Across all the lakes, the situation can be summarised as follows:
• Sewerage reticulation is nearly complete.
• For all but three lakes (Tarawera, Rotomahana, and Rotokakahi), the actions taken, underway, or planned should be sufficient to meet water-quality targets.
• For the most difficult challenge of Lake Rotorua, almost all sewage-derived nutrients are now removed, P is being precipitated in contributory streams, and a major step has been taken towards reduction in N outflows from farms.
Thus major progress has been made on the programme to restore the Rotorua lakes.
Factors Hindering or Helping Restoration
General political, economic, and social factors were not a significant influence in hindering or advancing restoration. Both major political parties assisted in the effort once convinced. The state of the economy did not affect funding, with favorable decisions made at both high and low points of the economic cycle. Social factors were not significant except specifically as below.
The main factors hindering or helping restoration related to information, institutions, and attitudes. The information gap comprised a lack of good science and inconsistent monitoring. The misguided scientific consensus that the lakes would eventually recover without further action was wrong. A comprehensive monitoring program in the early 1990s had been reduced and made sporadic.
The institutional reforms under the RMA were still working through to regional plans and regional policy statements. In the years to 2000, they had proven to be insufficient to trigger action. The MfE was still developing its role, as was the Commissioner for the Environment. In civil society, few national environmental organisations had impact on political decisions, apart from specific issues. None of them had significantly taken up fresh water quality issues.
Environmental awareness had been slow to develop in New Zealand. Only a few issues had attracted public attention. The major issues had been soil erosion, the preservation of indigenous forests and the treatment discharge of raw sewerage by Auckland City.30,31 Deteriorating water quality had been little recognised as a national issue.
The hardy freshwater scientists who survived the reforms of the 1990s were important in providing a scientific base on which to build reforms. The University of the Waikato contributed substantially through one or two key scientists, but more so especially after the establishment of the Chair in Lakes Management and Restoration.
Leaders in all three tiers of government contributed greatly once they were aware that problems needed to be solved. The MfE and the Commissioner for the Environment played a key role once engaged.32,33 The RMA codified environmental law and, in particular, required regional land and water plans to be produced and implemented. The Bay of Plenty Land and Water Plan prevented further enrichment of some lakes, and has been a useful, if limited, assistance for other work. The LWQS obtained advice and encouragement from environmental NGOs once its own efforts were underway.
Public attitudes to the lakes and the need for restoration changed and made it possible for political decisions to be made. The key to the change in public attitudes were the LWQS symposia.
The Lessons and Conclusion
In retrospect, the approach by LWQS was quite logical:
• develop the science,
• inform decision makers and opinion leaders about the science,
• change public policy,
• obtain funding,
• get physical works undertaken, and
• improve land management and change some land use.
We sought a scientific basis for lake restoration, we publicised the science, and we strategized on changing public policy. We spent no time on a master plan for the lakes, or on vision statements or mission statements. Rather we followed the advice of Professor Willy Ripl in 2001 on the sequencing of remediation measures: do whatever you can as soon as you can.
In 2002 with severe algal blooms affecting the lakes and the authorities indifferent, our task looked hopeless. Even in 2006, the Commissioner for the Environment warned that, ”Water quality will continue to get worse for some decades to come. In light of this bleak scenario, the challenge is enormous…”1 We found, however, that eutrophication can be reversed, and sometimes quickly. Waters that had annual blue-green algal blooms became free of blooms a season or two after nutrient inflows were greatly reduced. The restoration of some lakes was achieved much more quickly than we ever envisaged possible.
Effective action to restore the lakes required good science. The science was undertaken with some independence from the authorities responsible for the lakes. The LWQS symposia built up interest in the science and transmitted scientific knowledge to decision makers and the community.
Complacent public authorities were prodded into action by community groups. It took time, patience, determination, and commitment by dedicated people. Competent people in government authorities acted once the facts were clear.
Success was the result of hard work. We kept tight focus on better water quality and were not diverted by other issues. We were independent of the authorities. Changes such as different land use or reticulation of sewerage were neither easy nor cheap. They required persuasion and exhortation, some carrot, and some stick.
Agreement between stakeholders with conflicting interests required more than discussions around the table. Good leadership was needed from stakeholder groups and skilled mediators advanced agreements greatly.
Leading LWQS was a great journey shared with talented and interesting people. It was hard work, but was richly satisfying as the lakes improved far beyond our best hopes. Good water quality is the legacy that LWQS and others leave behind—but we have the challenge of working on until all the lakes are fully restored.