10.1 Introduction
10.2 Infrastructure Functions in the Water-Energy-Food Nexus
-
Basic well-being of the population;
-
Delivery of Government services; and
-
Enabling economic activity.
10.2.1 Maritime Transport Infrastructure
-
All incoming fossil fuel supplies from international locations are either offloaded to storage facilities, often located on vulnerable land along the coast, or domestically transhipped through major ports. These fossil fuels are typically the dominant source of fuel used to produce energy in the form of electricity, which then powers water treatment and distribution infrastructure and refrigerates stored food.
-
The imported fuels that pass through ports also drive land-based transportation networks that distribute food, bottled water, and other goods, and drive domestic shipping and recreational boating that underpins commercial and subsistence fisheries.
-
Gas imported through ports forms a significant source of heat for cooking food and boiling drinking water.
-
Jet fuel imported through ports is vital for air transport, and in particular supports the key economic role of tourism in the region.
-
Ports provide for the extensive domestic and international commercial fisheries industries that are a significant component of local and regional economies, and a critical source of food for many countries.
-
For countries with minimal arable land (atoll-dominated countries, for example), imported food via sea transport forms a major component of people’s diet to supplement locally available produce.
-
Domestic ports and harbours provide the opportunity for inter-island movement of food, both imported and exported from domestic agriculture, aquaculture, and other primary producers, and for movement of other supplies and produce between remote communities.
-
Domestic harbours are the safe base and hub through which many local fishermen access the seas surrounding their islands to undertake subsistence fishing.
10.2.2 Water, Sanitation, and Hygiene (WaSH) Infrastructure
-
Alternative water supply technologies such as RO have high energy costs and if not using renewable energy, require fuel to be imported, providing further cross linkages with transport infrastructure.
-
Similarly, energy, and therefore fuel, is required for water treatment plants and pumps for boreholes and surface water intakes. As highlighted above, energy supply disruptions can lead to households storing more water to mitigate against intermittent supplies. This can contribute to poorer water quality and health outcomes.
-
Unsustainable groundwater use, leading to drawdown or salinisation of aquifers, requires higher energy inputs due to increased pumping and treatment requirements.
-
Life on Pacific atolls can be “harsh and precarious,” due to their low agricultural productivity and highly porous soils, coupled with limited available land area, leading to food insecurity and the need to import food (Terry and Chui 2012). Attempts to improve productivity through fertilizers and pesticides risk contaminating the limited freshwater reserves and impacting adjacent coastal ecosystems.
-
More research is required into safe rearing practices for livestock that better protects freshwater sources in the Pacific context (MacDonald et al. 2017). For example, the proximity of domesticated pigs to community water sources increases the risk of leptospirosis through contamination of freshwater by urine.
10.2.3 Coastal Protection Infrastructure
-
For many island communities agricultural crops, in particular taro crops grown in low-lying freshwater wetlands, form staple food sources but can be destroyed by saline ocean water from wave overwash and storm surge processes, or damaged through erosion (e.g., impacts from Cyclone Pam on outer islands of Tuvalu) (Taupo and Noy 2017).
-
Freshwater lagoons, wetlands and shallow groundwater aquifers that form drinking water reserves can become contaminated with salt water (Storlazzi et al. 2018), destroying their viability for decades into the future (e.g., impacts from Cyclone Percy on the atoll of Pukapuka in the northern group of the Cook Islands) (Terry and Falkland 2010).
-
Protection of other infrastructure within the coastal zone that supports the water-energy-food interdependencies, including water distribution infrastructure, transport infrastructure (road, port, and air), power supply infrastructure, fuel storage etc., from the impacts of these extreme ocean events.
Country | Coastline length (km) | Reported coastal protection types |
---|---|---|
Cook Islands | 120 | Concrete sea walls, rock boulder revetments, groynes, rock breakwaters, grouted coral sea walls, geotextile sandbag revetments, gabion baskets, beach planting, beach replenishment |
Fiji | 1,129 | Mass concrete seawalls, reinforced concrete seawalls, rock revetments, rubber tires, gabion baskets, mangrove planting |
Federated States of Mirconesia | 6,112 | Grouted coral seawalls, stacked coral boulders |
Kiribati | 1,143 | Small-stacked sandbags, grout-filled and mortared sandbags, reinforced concrete, grout mattress, tetrapod armour units, rock revetments, gabion baskets, stacked coral, grouted coral, planted mangroves |
Republic of Marshall Islands | 370 | Rock rip-rap revetments, sandbags, vertical concrete block or cemented coral walls, concrete armour units, gabion baskets filled with coral gravel, stacked tires, scrap metal and old heavy machinery |
Niue | 64 | Concrete seawalls |
Nauru | 30 | Coral boulders, concrete seawalls, rock seawalls |
Palau | 1,519 | Rock riprap, grouted rock, vertical concrete |
Papua New Guinea | 20,197 | Stacked rock, bricks, sandbags, tree trunks, gabion baskets, concrete filled tires |
Samoa | 403 | Grouted stone walls, rock revetments, groynes, beach replenishment, mangrove planting |
Solomon Islands | 9,880 | Rock revetments, stacked rock behind wooden piles, mangrove planting, vertical concrete walls, concrete armour units (tetrapods), gabion baskets |
Tonga | 419 | Limestone/coral boulders, mangrove planting, grout-filled bags |
Tuvalu | 24 | Vertical concrete walls, gabion baskets, concrete cubes, steel drums filled with concrete |
Vanuatu | 2,528 | Vertical concrete walls, stacked coral, grouted coral, gabion baskets, revegetation |
Timor Leste | 735 | Rock revetments, concrete armour units, mangrove planting, coastal and marine protected areas |
10.3 Climate-Related Vulnerabilities
10.3.1 Maritime Transport Infrastructure
-
More regular overtopping of the wharves, breakwaters, and ancillary facilities, making them unsafe or undesirable for use by the community;
-
Reduced high-tide freeboard for vessels at berth, compromising the ability to safely load and unload cargo;
-
Permanent inundation of the shoreline connections and/or wharves, making the infrastructure unsafe or unusable; and
-
Increased maintenance requirements due to increased nearshore wave heights and cyclonic activity.
10.3.2 WaSH Infrastructure
10.3.3 Coastal Protection Infrastructure
10.4 Management and Adaptation
10.4.1 Infrastructure Adaptation Options
Effect of climate change | Impact on infrastructure | Potential adaptation responses |
---|---|---|
Marine transport infrastructure | ||
Changes to seasonal climatology such as winds, air temperature, ocean currents, and waves | Implications for navigation and berthing of vessels | Altered operating rules for vessels entering port, modifications to navigation channels, and harbour wave protection structures |
More frequent occurrences when vessels cannot enter port or safely transfer cargo to island barges | Modify harbour facilities to provide additional shelter or safer passage during broader window of conditions, consider alternative/backup unloading facilities, increase storage of goods held on-island | |
Implications for operation of cargo unloading equipment (such as cranes), cold storage, etc. | Alter operations to accommodate periods of down-time, adapt cargo-handling methods to accommodate higher winds or air temperature, improve efficiency of cold storage facilities | |
Sea level rise | More frequent inundation of wharf facilities | Structural changes to raise wharf deck levels and lift other infrastructure |
Increased wave conditions impacting port due to deeper water or increased winds | More frequent maintenance of wave protection structures | |
Modifications to wave protection structures | ||
Landward retreat of adjoining coast | Protection of adjacent areas of coast (soft or hard), modifications to interface areas of wharves/surrounding terrain | |
More intense cyclones | More frequent and/or more intense storm surge inundation of wharves and other port infrastructure | Raise level of wharf decks and other infrastructure, adapt land-side facilities to tolerate short periods of inundation, modify coastal protection to reduce impacts of wave setup and infragravity waves, modify cyclone preparations to accommodate more severe conditions |
Larger waves and higher water levels impacting on coastal protection structures | Raise and increase armouring of protection structures, increase maintenance top-ups of armouring, adapt protection structure designs to tolerate more intense conditions | |
Additional wind damage on cargo handling and other land-side equipment/facilities | Strengthen cargo handling equipment and storage facilities, modify cyclone preparations to accommodate more severe conditions | |
WaSH infrastructure | ||
Changes to seasonal and annual rainfall cycles | Water shortages due to insufficient storage | Increase storage and catchment areas, more diverse water sources developed |
Reduced recharge for springs and freshwater lens | Sustainable yields identified, more diversity in sources | |
More intense rainfall events | Increased flood risk and damage to infrastructure | Diverse water supply sources |
Cross contamination of freshwater from sanitation infrastructure | Improved water sources with less exposure to surface water inflows, improved design and siting of sanitation infrastructure | |
Sea level rise | Increased saltwater intrusion for freshwater lens | Limited ability to adapt to this impact |
More intense cyclones | Increased incidence of wave overtopping for freshwater lens | Limited ability to adapt to this impact |
Extreme rainfall and wind speed damage to infrastructure | Diverse water supply sources | |
Increased temperatures | Changes in microbial growth | Wider use of improved water sources, wider use of system or household disinfection systems |
Increases in algal growth | Improved catchment protection Mechanical and chemical treatment | |
Engineered coastal protection infrastructure | ||
Sea level rise causing increased water levels at protection structure | Increased frequency and volume of overtopping | Raise structure crest to reduce overtopping or adapt backshore areas to tolerate higher overtopping flows |
Larger waves caused by higher wind speeds or deeper water at protection structure | Higher wave loading on armour units | Place larger armour over existing units or create berm/beach in front of structure to induce early wave breaking and dissipation |
Increased frequency and volume of overtopping | Raise structure crest to reduce overtopping or armour backshore to tolerate higher flows or create berm/breakwater/beach in front of
structure to induce early wave breaking and dissipation | |
Landward retreat of shoreline under rising sea level or faster lagoon currents | Erosion of sand from around ends of protection structures | Extend structure alongshore or re-align ends to accommodate new shoreline position |
Beach level lowers in front of structure | Extend or create deeper toe (base of protection structure) using additional armour material (rock, sand-filled geotextile bags etc.), sheet piling or concrete |
10.4.2 Pacific Strengths and Barriers to Infrastructure Adaptation
10.5 Conclusion
-
Framing infrastructure investment using the water-energy-food nexus is vital to ensure that the interconnectedness of infrastructure is not missed and to prevent maladaptation. Ad-hoc or individual infrastructure improvements will not increase the resilience of PICTs.
-
Building knowledge and capacity within the region to:
-
Mainstream climate risk considerations as part of the initial design of new, and adaptation of existing infrastructure, such that integration with natural environmental systems and local knowledge is captured within designs, and that expertise is retained;
-
Improve design standards for infrastructure; and
-
Support maintenance of infrastructure across its functional life.
-
-
Continuing to close the gap in scientific knowledge and use traditional knowledge of island-specific processes, such that infrastructure interventions are fit-for-purpose in terms of their own longevity, the service they provide, and the impact of the site-specific environment within which they sit.
-
Ensuring whole-of-life sustainability for infrastructure interventions and integration of engineering and nature-based solutions, such that climate adaptation works appropriately reflect the scale required, and due consideration is given to the specific environmental and cultural context.