17. NATURAL HAZARDS
NGAA MOOREAREA AO TUROA
17.1.1 Natural hazards are environmental events that are not caused by human interference with the environment but occur as a result of nature’s activities. However, the magnitude or the consequences of these events can be exacerbated by human activity, such as increased frequency and severity of landslips through poor land management practices. Natural hazards are a concern, as they have the potential to affect human health, property, and the environment, yet they cannot necessarily be managed in the same manner as natural resources. The hazards that are most likely to occur in Waikato-Tainui include flooding, earthquakes, volcanic eruptions, landslips, severe weather events (e.g. tornadoes, drought), fire, and tsunami.
17.1.2 Global warming and climate change are likely to result in a rise in sea levels; more extreme weather events; changes to rainfall patterns; increased erosion; changes in the population density and distribution of fish and wildlife; and changes in the viability of cultural and/or spiritual resources and activities. Climate change caused by human activity and its effects are a controversial issue both globally and nationally. The impacts that climate change has on our indigenous flora and fauna is largely unknown, therefore it is vital that Waikato-Tainui actively engage and contribute to any nationally led initiatives, policies, guidelines and programmes on climate change. Most importantly, Waikato-Tainui wants to avoid any disruption that climate change causes to indigenous ecosystems, Waikato-Tainui cultural and/or spiritual beliefs and/or practices. Note that references to climate change in the Plan are to climate change potentially caused by human activity.
17.1.3 The potential effects of climate change on water bodies could cause increasing droughts in some areas that could reduce summer low flows that could create greater stress for aquatic life. Increases in storm flows can increase the potential to scour life and habitats out of water ways (particularly smaller more open streams).
17.1.4 The region is prone to flooding particularly as it is susceptible to tropical storms. There are steep river catchments that receive intense and localised rainfall, the Waikato River has a large and extensive catchment, there are low lying areas of flood plain that are intensively farmed and some land management practices allow, or have allowed extensive land clearance followed by increased runoff and erosion. An area at substantial risk of flooding is the Lower Waikato River from Ngaaruawaahia northward. The confluence of the Waikato and Waipaa Rivers is highly prone to flooding. Flooding in coastal areas may arise from tsunamis, or from high tides coupled with storm events.
17.1.5 Natural hazard risk management is very important to ensuring the safety of people, communities, marae, and areas of cultural and spiritual significance. Activities and resource use practices should occur in a way that does not increase the risk of a natural disaster occurring or increase the magnitude of the effects from a natural event should it occur in an integrated holistic manner.
17.2.1 Inappropriate subdivision, land use, or development can increase the risk of some natural hazards occurring and the magnitude of any effects when hazardous events do occur. There is concern that land use regulations have, over the years, permitted the subdivision and development in hazard prone areas. For example, building houses in an area prone to flood or tsunami creates a risk that residents or buildings are endangered if a flood or tsunami was to occur.
17.2.2 Coastal erosion and land instability cause environmental as well as cultural and/or spiritual impacts particularly on waahi tapu and sites of significance (e.g. human remains being exposed through coastal erosion and land use creating landslips.
17.2.3 General land use issues are addressed in other chapters, such as Chapter 21, ‘Te whenua – land’; Chapter 25, ‘Ngaa whakaritenga moo ngaa whenua o Waikato-Tainui – land use planning’; and Chapter 26, ‘Waihanga matua – infrastructure’, and are not considered further in this chapter. This chapter focuses on land use as it relates to natural hazards.
17.2.4 Affected property owners may have an expectation that properties already developed in hazard zones should be permitted to erect protection structures. The erection of these structures may enable the wellbeing of an individual or group but may have an adverse effect on landscape, indigenous fauna and flora, and culturally and/or spiritually sensitive sites.
17.2.5 It appears that “hard” engineered solutions are used too widely and more natural “soft” solutions to natural hazards (particularly erosion and stability) should be considered. Additionally, these structures sometimes magnify the local effect that they are designed to prevent (e.g. sea walls may provide an unnatural barrier to wave action which subsequently may cause greater gouging of the sand at the base of the sea wall when wave action occurs).
17.2.6 Balance is required between utilising hazard management protection mechanisms, such as groynes, walls, and stop banks to protect property, and protecting areas of significance to Waikato-Tainui and avoiding adverse effects on the environment.
17.2.7 Climate change is likely to result in sea level rise, more frequent and intense rainfall as well as increased frequency and duration of drought. A shift is needed in the way hazards are managed to protect developments in areas that may be at risk in the future. Climate change has the potential to change physical and natural processes. This is of particular concern if climate change is exacerbated by human activity. There is concern that human activity and the cumulative effect of discharges, farming, industry, and commercial practices, and deforestation may adversely contribute to climate change, global warming, and the reduction in the ozone layer.
17.3 Objectives, Policies & Methods
Objective – land use and structures
17.3.1 Land use and the construction of structures occurs in a way that does not increase the risk or magnitude of a natural hazard event, and that does not increase the risk or effects on human life or activity in the event that a natural hazard event occurs.
Policy – land use and structures
220.127.116.11 To ensure that land use and structures do not increase the risk or magnitude of a natural hazard event, and does not increase the risk or effects on human life or activity in the event that a natural hazard event occurs.
(a) New land use and structures that increase the risk or magnitude of a natural hazard event shall be avoided. Note: Preference is given to any new or changing land use, subdivision or development avoiding, rather than mitigating, any hazard.
(b) Existing land use, activities, and structures in zones where natural hazards occur are encouraged to change land use or activities and shift, abandon or suitably modify structures to withstand the potential effect of a natural hazard event.
(c) Consider taangata whenua historical knowledge of natural hazards when considering land use, activities, or structures under this policy.
Objective – risk management
17.3.2 The risk of adverse effects on human, cultural, spiritual, or environmental wellbeing shall be prioritised over risks to individual properties when assessing natural hazard risks and/or the need for hazard protection structures.
Policy – risk management
18.104.22.168 To ensure that human, cultural, spiritual, or environmental wellbeing is appropriately considered when assessing natural hazard risks and/or the need for hazard protection structures.
(a) Policy 22.214.171.124 and the associated methods are noted as a key means to manage risk.
(b) Where it is practical, and environmentally, culturally, and/or spiritually preferable, a ‘soft’ engineering solution should be utilised over a ‘hard’ solution (e.g. the use of swales rather than concrete channels).
(c) New land use and structures shall avoid creating actual or potential adverse effects on natural hazards which subsequently causes adverse affects on human, cultural, spiritual, or environmental wellbeing.
(d) Existing or new structures or land use that requires the use of hazard protection structures that could adversely affect human, cultural, spiritual, or environmental wellbeing are generally not supported.
(e) In the event that an existing or proposed hazard protection structure adversely affects human, cultural, spiritual, or environmental wellbeing then alternative solutions are encouraged and expected.
(f) Where there is existing development and the effects on cultural and/or spiritual values and the environment are adverse, the concept of ‘managed retreat’ where existing structures are not replaced or maintained and no new structures are allowed to be erected, should be applied.
(g) Hazard management structures, activities, and schemes and their ongoing function should strive to maintain and restore ecosystem function and habitat, and cultural and/or spiritual wellbeing.
(h) The cumulative adverse effect of land use and structures on natural hazards shall be avoided or managed consistent with the policies in this chapter, such that there is no increased risk to human life, structures, cultural, spiritual or environmental wellbeing.
(i) Notwithstanding the above methods, protecting life is a priority in hazard management structures, activities and schemes.
(j) A practical balance between natural hazard management and the restoration and protection of cultural, spiritual and environmental wellbeing is encouraged.
(k) Where culturally and/or spiritually sensitive sites or sites of significance are subject to natural hazards, in which human intervention has played no role, then Waikato-Tainui should be advised to enable the correct protocols and procedures to be adopted in order to address the situation.
(l) In the event that human remains or koiwi are exposed through a natural hazard event, the protocols set out in Chapter 16, ‘Ngaa taonga tuku iho, ngaa waahi tapu, ngaa waahi tuupuna – valuable historical items, highly prized sites, sites of significance’, apply.
(m) When developing integrated management plans, they shall consider the management of natural hazards.
(n) Maintain a register, in partnership with other stakeholders (e.g. local authorities), of natural hazards in the Waikato-Tainui rohe. This may include merely being aware of which entity keeps such a register.
Objective – climate change
17.3.3 The cause and effects of climate change are understood and prepared for within the Waikato-Tainui rohe.
Policy – understanding and managing adverse effects of climate change
126.96.36.199 To ensure that the causes and effects of climate change are understood and prepared for within the Waikato-Tainui rohe.
(a) The use of ozone depleting chemicals and activities is not supported.
(b) Any known or potential adverse effects of climate change on Waikato-Tainui are prepared for and managed.
(c) Any adverse effects of global or national climate change policy on Waikato-Tainui are managed.
(d) Waikato-Tainui is engaged and consulted on regional, national, and, where practicable, global climate change policies and process.
(e) The effects of resource uses or activities that can aggravate climate change are managed.
Note that other methods in this chapter contribute to managing the adverse effects of climate change.