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MULTIPLE STRESSES, VEILED THREAT: SALTWATER INTRUSION IN SAMOA Presented at the Samoa Conference III: Opportunities and challenges for a sustainable cultural and natural environment 25-29 August 2014 National University of Samoa, Apia, Samoa By Leo Berthe, Denis Chang Seng, Lameko Asora Introduction Facing a wide range of natural, human and financial constraints, Pacific Small Island Developing States (SIDS) must overcome significant challenges in managing their water resources. Threatened by a complex system of burdens, Pacific SIDS struggle to both preserve their water supply and build the capacity needed to manage efficiently a fragile but vital resource. In the region, water-related issues are as numerous as the measures, tools and approaches involved in responding to them. Although the Pacific SIDS share a number of characteristics and vulnerabilities, it is important to note that the various states differ considerably in terms of geography, geology and population. This in turn creates distinct water and governance challenges. Drinking water coverage well illustrates these disparities: as of 2012, three out of five Pacific SIDS were known to provide improved drinking-water sources to over 80% of their population, but only 56% of the overall people of Oceania 1 had access to safe drinking water 1 Oceania here does not include Australia and New Zealand but American Samoa, Cook Islands, Fiji, French Polynesia, Guam, Kiribati, Marshall Islands, Micronesia (Federated States of), Nauru, New

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MULTIPLE STRESSES, VEILED THREAT: SALTWATER

INTRUSION IN SAMOA

Presented at the

Samoa Conference III: Opportunities and challenges for a sustainable

cultural and natural environment

25-29 August 2014

National University of Samoa, Apia, Samoa

By Leo Berthe, Denis Chang Seng, Lameko Asora

Introduction

Facing a wide range of natural, human and financial constraints, Pacific Small Island

Developing States (SIDS) must overcome significant challenges in managing their water

resources. Threatened by a complex system of burdens, Pacific SIDS struggle to both preserve

their water supply and build the capacity needed to manage efficiently a fragile but vital

resource.

In the region, water-related issues are as numerous as the measures, tools and approaches

involved in responding to them. Although the Pacific SIDS share a number of characteristics

and vulnerabilities, it is important to note that the various states differ considerably in terms of

geography, geology and population. This in turn creates distinct water and governance

challenges. Drinking water coverage well illustrates these disparities: as of 2012, three out of

five Pacific SIDS were known to provide improved drinking-water sources to over 80% of their

population, but only 56% of the overall people of Oceania1 had access to safe drinking water

1 Oceania here does not include Australia and New Zealand but American Samoa, Cook Islands, Fiji,

French Polynesia, Guam, Kiribati, Marshall Islands, Micronesia (Federated States of), Nauru, New

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(UNICEF/WHO, 2014). This regional discrepancy is explained by the prominent and skewing

effect of Papua New Guinea; while the country represents 70% of the Pacific population, less

than 50% of its people use an improved drinking water source2.

Despite the diversity, Pacific SIDS still face a wide range of common, cumulative and mutually

reinforcing natural and human challenges to providing adequate water to their population, both

in quantity and quality. Saltwater intrusion, the “phenomenon of the penetration of seawater into

coastal aquifer and bodies of surface freshwater which have a permanent or periodic

connection to the sea” (Cieśliński R., Bogdanowicz R., Drwal J., 2009), is one of these shared

issues. It is particularly relevant for islands States where a significant supply of water is drawn

from groundwater (e.g. 35% in Samoa), because of the higher potential consequences and

impacts of saltwater intrusion on their freshwater resource. Though widely acknowledged,

saltwater intrusion remains a poorly researched and documented phenomenon in the Pacific

region (see Table 1).

Caledonia, Niue, Northern Mariana Islands, Palau, Papua New Guinea, Samoa, Solomon Islands, Tokelau, Tonga, Tuvalu, Vanuatu. 2 In this regard, Papua New Guinea remains one of the three countries in the world (with Democratic

Republic of the Congo and Mozambique) to have less than half of its population with access to improved drinking water. (UNICEF/WHO, 2014).

Figure 1: Map of Samoa. Source: Government of Samoa, 2006.

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In this regard, Samoa (see Figure 1) is no exception and will serve as a representative of the

Pacific SIDS in approaching and discussing saltwater intrusion. Samoa faces both

vulnerabilities to saltwater intrusion and issues in the assessment and management of its water

resources. Producing a reliable assessment of the country’s current water vulnerability

represents an extremely problematic venture and a hindrance to building resilience and

alleviating poverty in the country. From these observations, key questions arise:

1. What is the level of Samoa’s vulnerability to saltwater intrusion?

2. What is the current state of knowledge regarding saltwater intrusion in Samoa?

3. How are national authorities addressing this issue and what are the key challenges

they are facing?

Samoa constitutes the core focus of this case study, but it does not prevent these questions

from being relevant at the regional scale. In this respect, this contribution aims to document the

challenges raised by the current saltwater intrusion in Pacific SIDS and to assess the related

efforts, answers and progress made in recent years in Samoa. It will draw on this particular

case to point out several recommendations to the Samoan national authorities and

development partners that are applicable and relevant to other Pacific SIDS. By doing so, this

contribution hopes to lay the foundations for extended assessment work in the future as well as

potential monitoring mechanisms that will better inform decision making on groundwater

management.

Freshwater in the Pacific SIDS: a Fragile Resource for a Myriad of Countries

Challenges to freshwater security

While contributing marginally to greenhouse gas emissions, Pacific SIDS bear the worst brunt

of climate variability and change. Sea level rise, ocean acidification, and altered temperature

and precipitation pattern are a few of the effects associated with climate change that will have a

disproportionate effect on these island nations. Physically isolated with limited and vulnerable

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resources, these states must secure the safety and sustainability of their natural resources to

cope with a changing environment.

In particular, freshwater is a fragile and threatened resource across the Pacific. Freshwater

supply and access is endangered by natural hazards, climatic season variation, climate

change, and human impacts. These factors create an undeniable reality that compels an

important movement for the Pacific states towards the sustainable use of water in the region.

Prone to recurrent water-related natural hazards, the Pacific SIDS efforts to secure safe

drinking water are frequently hindered by tropical cyclones and storm surges. Expected to

increase in intensity in the near future (IPCC WGI, 2014), these events destroy water storage

and management facilities, and provoke floods and saltwater intrusion, causing brutal water

crises that may escalate to a state of emergency. The Federated States of Micronesia

authorities reached this point in 2007, after been hit by king tides that flooded and destroyed

taro crops.

Most Pacific SIDS also remain extremely vulnerable to any climatic seasonal variation. Extreme

events such as El Niño3 and La Niña

4 periodically produce wet and dry climate cycles that could

lead to, depending on the location of the islands, abundant rainfall episodes or intensive

periods of drought, jeopardizing safe access to drinking water (e.g. in 2011, Tuvalu and

Tokelau both declared a state of emergency due to drought crises). This represents a

particularly prominent issue for Pacific SIDS that are strongly reliant on rainwater and have

limited groundwater resources at their disposal, such as in atolls like Kiribati, Nauru, Republic

of Marshall Islands and Tuvalu.

In addition, Pacific SIDS’ water resources are negatively affected by climate change associated

slow-onset events. For instance, sea level rise, “one of the most widely recognized climate

3 El Niño is a warming of the sea surface temperature phenomena associated with changes in the

atmospheric circulation in the tropical Pacific and worldwide. It usually occurs every two to seven years, causing droughts in most Pacific SIDS. 4 La Niña is associated with cooler than normal water temperatures in the Equatorial Pacific Ocean and its

impacts tend to be the opposite of El Niño (United States National Oceanic and Atmospheric Administration).

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change threats to low-lying coastal areas on islands and atolls” (IPCC, WGII, 2014), is a

considerable obstacle to securing sustainable water resources in the region. Due to the natural

features of islands, Pacific SIDS and especially low-lying islands are expected to experience

intensified storm and cyclone impacts, coastal erosion, flooding and saltwater intrusion in the

future.

Different human and development stresses make the outlook of safeguarding freshwater

resources even bleaker. Economic growth and increasing population escalate the water

demand while evolving consumption patterns and lack of sanitation tend to increase water

pollution, particularly in growing socioeconomic urban centres. By intensifying the competition

for water, these impediments add pressures to an already endangered and limited resource.

As highlighted in Figure 2, the culmination of the aforementioned factors – flooding, drought,

sea-level rise and growing human consumption – is an increased vulnerability to saltwater

intrusion for the Pacific SIDS.

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Figure 2: Possible causes and drivers of saltwater intrusion. Source: Authors

Table 1 summarizes and highlights reported vulnerabilities and challenges on freshwater

associated with saltwater intrusion, in selected Pacific countries.

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Table 1: Reported saltwater intrusion in selected Pacific SIDS

Country

Topography and freshwater resource

5

Is saltwater intrusion observed, expected or both?

6

Saltwater intrusion reporting7

Mela

nesia

Solomon Islands

Topography

Coral atolls, volcanic islands

Both

“Salt-water intrusion, storm surge and flooding in low-lying coastal areas of the main islands and the atolls such as Ontong Java are already threatening food crops and livelihoods”, National Adaptation Programme of Action (NAPA), 2008.

Water

Surface water, rainwater, thin groundwater lens

“Studies suggest that hundreds of small islands could permanently inundate and their cultural heritage lost in the event of a one meter sea-level rise. Intrusion of salt water from rise in sea level affect groundwater resources, especially small atolls and low-lying islands which rely on rainfall or groundwater for water supplies”, NAPA, 2008.

Mic

ronesia

Marshall Islands

Atolls

Both

“During the most recent El Nino event (1997-1998), many in the community were forced to use the ocean to bath and to drink the groundwater. In some situations this source of water was polluted due to: salt intrusion of groundwater resources, sewerage and sullage water discharges entering the groundwater aquifers, proximity to burial sites, and materials being leached from animal droppings and domestic solid waste”, 2000.

Rainwater

“Public health and nutrition problems may arise from the intrusion of salt water and the general reduction in the quality of the ground water resources of the more highly populated atolls”, 2000.

“Future changes in climatic conditions are likely to affect water supply and quality in the following three major ways. First, through a rise in sea level that may increase problems of salt intrusion to the ground water system”, 2000.

Palau

Volcanic, high limestone, low limestone, atolls and a combination of volcanic and limestone.

“In 1998, saltwater intrusion associated with abnormally high tides caused extensive damage to taro patches (traditional food supply) in Palau (N) Salt water acts like a poison to taro, with crops losses as high as 75 to 100%”, 2002.

5 Freshwater information are obtained from the different national Integrated Water Resources Management programme's Diagnostic Reports, published by SOPAC

in 2007. 6 Red: Observed saltwater intrusion; Orange: Expected; Green: Both.

7 Except where otherwise noted, quotes are extracted from the latest national communication to the United Nations Framework Convention on Climate Change.

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Surface water, rainwater, groundwater (lens are thin and mostly non potable).

There will be enhanced coastal erosion, loss of land and property, dislocation of people, reduce resilience of coastal ecosystems, and saltwater intrusion into freshwater sources”, 2002.

“Soil salinization will make agriculture difficult to sustain into the next century”, 2002.

Poly

nesia

Cook Islands

Volcanic islands, coral atolls

Both

On the Southern group of Islands: “there is no chemical water treatment on any of the islands thus water quality is non-potable and often brackish indicating that exploitation of the water lens is at the limit of sustainability, with saltwater intrusion an increasing threat”, 2011.

Southern Group of Islands:

surface water

Northern Group of Islands: rainwater, groundwater

“Despite limestone cliffs separating the agricultural growing areas the sea storm surges and cyclones can still lead to salt-water intrusion into the low-lying swampy areas. Base line salinity levels still need to be established; however it is clear that any sea level increase is going to be an issue for the island of Mangaia and other makatea type islands”, 2011.

Samoa

Volcanic islands

Both

“Water resources are particularly vulnerable to the effects of climate change. Significant problems associated with climate change include: salt water despoiling ground water and coastal springs as sea levels rise”, 2010.

Surface water, groundwater

“The risk of saltwater inundating groundwater is expected to increase as sea levels rise. The recharging of groundwater is expected to lessen as annual rainfall lessens. Rising sea levels will also affect coastal springs as current boundaries become flooded”, 2010.

Tuvalu

Atoll islands

Both

“The most damaging effects of climate change are tropical cyclones, coastal erosion, salinity intrusion and drought. These have been noted to affect crops, fruit trees and human livelihood”, NAPA, 2007.

“Groundwater resources have been polluted by saltwater intrusion and waste leachate. Therefore, no longer suitable for human consumption”, NAPA, 2007.

Rainwater, groundwater

“Intrusion of saltwater in Tuvalu will also affect ground water availability for plant growth, and food crop productivity and security”, NAPA, 2007.

Source: Authors

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The table reports on selected islands with different topographies and water resources from different

regions across the Pacific. Although the table is a sample, all the listed countries assert cases of

saltwater intrusion, disclosing their concern and vulnerabilities on a phenomena leading to a wide range

of impacts. The table indicates a high level of concern about the significant effects and potential risks of

saltwater intrusion, especially due to likely sea level rise: saltwater intrusion is widely acknowledged as a

significant threat with tough and lasting effects on water supply, health, agriculture, cultural heritage and

the overall resilience of these countries. However, because of a general lack of assessment, few Pacific

SIDS provide knowledge and scientific based evidences on saltwater intrusion.

Saltwater intrusion in Samoa: genuine threat, uncertain effects, modest solutions

“Our land, livelihoods, culture and ecosystems are fundamentally threatened by sea level rise and the

changing climatic conditions” (Government of Samoa, 2010)

Samoa consists of two main islands (Upolu and Savai’i) that accommodate around 180.000 inhabitants.

While the topography is rugged and mountainous, 70% of the Samoan population and infrastructures are

located on the low-lying area. This represents a blatant issue considering the country’s high exposure to

natural disasters, one of the main challenges to secure quality water in the country.

In addition, precipitation pattern8 and the heavy seasonal variability lead to recurrent and extreme

droughts and floods, the latter of which is likely to increase due to significant intensification of rainfall

events (Hay, 2006). Sea level rise is another key challenge to take into account in Samoa. Even under a

low emissions scenario, the rise of sea level is projected to be in the range of 5-15cm by 2030 (Pacific

Climate Change Science Program, 2011); it is likely to exacerbate the impacts of other episodic coastal

hazards, triggering unreliable supply and poor quality water notably through saltwater intrusion.

Samoa essentially relies on two sources to obtain its freshwater: surface water (around 65%) and

groundwater (around 35%), the latter of which is expected to increase in the near future (Government of

8 Data shows no clear trend in annual rainfall over the last 60 years and model results for rainfall projections are not

consistent (Pacific Climate Change Science Program, 2011).

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Samoa, 2013b). During a normal dry season, surface water reserves are gradually exhausted and

sometimes insufficient to provide reliable water services in some parts of the islands. To cope with the

situation and to boost water availability, the Samoan Water Authority (SWA) as well as some major hotels

and other large establishments, have implemented their own water production boreholes (Government of

Samoa, 2013b). This could become a regular practice in the future, considering the existing and

increasing pressures on water: sustained population growth9, response to the needs of tourism

10,

hydropower generation, and other commercial water uses11

are likely to cause surface and groundwater

extractions to soar. This is of particular concern in light of the general lack of present or projected data on

water demand and supply.

In the context of both increasing pressures and uncertainty, the saline contamination of some

groundwater lenses and coastal springs is emerging as a very serious challenge in Samoa.

Institutional changes and governance progress: between commitments and actions

Rethinking water management is irrefutably one of the most prevalent and substantial challenges for the

Pacific States to build water resilience. The Samoan authorities have not turned a blind eye to this issue

and have made major efforts to clarify and improve their water governance framework and institutional

arrangements.

Through the Water Resources Management Act of 2008, the government clearly reaffirmed its sole right

to the conservation, maintenance and sustainable use of water in the country. Enforced in 2009, its full

implementation remains disputed, notably by some villages that maintain independent water schemes.

While 80% of the land in Samoa is customary, and de facto under the direct stewardship of the traditional

9 The annual population growth was of 0.64% between the two last censuses (2005 and 2011). The Samoan Bureau

of Statistics has predicted the annual population growth rate to be between 0.7% and 1.5% between 2011 and 2021 (Government of Samoa, 2013b). These data should be interpreted with cautious considering the uncertain and varying influence of emigration in the country. 10

Tourism -high water consuming activity per excellence- is playing an increasing important role in the economy (20% of the GPD in 2012) while governmental objective is to increase the number of tourist by 5 to 7% per year until 2016 (Government of Samoa, 2012a). 11

The largest water consuming commercial activities in the country are the brewery, the coconut factory and the different bottled water companies.

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authorities, the state’s perceived ownership of water resources is a controversial topic that has already

caused some distrust towards the government.

To manage these conflicts and to mitigate their impacts, the Independent Water Schemes Association

(IWSA), under the supervision of the Ministry of Women Community and Social Development (MWCSD)

was established in 2008. The IWSA aims to provide reliable supplies and safe water to communities and

serves to date 30,000 people, approximately 17% of the Samoan population (Government of Samoa,

2012b). This new entity also acts as a facilitator and mediator between government and communities.

Efforts are made to reach the entire community, with a special focus on women. At the household level,

women usually play a key and active role in water management but remain traditionally excluded from

most of the decision-making process (Government of Samoa, 2012b). To overcome this contradiction and

hurdle, the IWSA has instituted that “village water committees must have at least two female members on

the IWS Water Committee” (Government of Samoa, 2012b). Although the percentage of water managed

by the ISWA is not clear, this represents an important step towards a more integrated and participatory

water management approach.

Aside from a better inclusion of the population, much has also been done to enhance inter-institutional

cooperation and coordination between the different governmental agencies. The establishment of the

Joint Water Sector Steering Committee (JWSSC) in 2009 is an instance of such consolidation. The

JWSSC is a high level committee12

that meets quarterly, attended by the Chamber of Commerce, the

Samoa Umbrella of NGOs, the IWSA and the CEOs of government ministries13

–although attracting them

remains “a persistent challenge” (Government of Samoa, 2012b). Through these meetings, the JWSSC

coordinates the implementation of reforms and provides leadership, policy guidance and monitoring for

the water sector (Government of Samoa, 2012b). These changes allow for permanent coordination while

reinforcing already existing ad-hoc cooperation between ministries. The reorganisation prevents water

12

According to the water sector institutional framework, the JWSSC is acting between the Cabinet and the Ministries. 13

Ministry of Natural Resources and Environment (MNRE), Ministry of Works, Transport and Infrastructure (MWTI), Ministry of Women Community and Social Development (MWCSD), Ministry of Agriculture and Fisheries (MAF), Ministry of Finance (MOF).

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issues from being addressed in isolation and stands as an operational way to make and implement

decisions collectively.

By and large, a set of regional commitments and national pragmatic diagnosis and action plans have

paved the way to an improved integrated management of water resources in Samoa. The Water for Life

sector plan is an essential piece in this respect, demonstrating the importance given by the national

authorities to the water management challenges they are facing:

“The management of water resources must be well planned and effective (N) The linkages between

water supply development initiatives and the initiatives in the agriculture, food, energy, health, education

and other key sectors must be clearly understood and carefully managed, in order to benefit from the

inherent synergies and to minimize or avoid negative cross-sector impacts (N). Good water management

is so fundamental to human and economic development and to the maintenance of ecosystems, that we

cannot afford to fail”14

.

Periodically updated since the initial document was issued in 2008, the Water for Life plan assesses the

performance of the water and sanitation sectors and spells the way forward through clear objectives and

strategies. Through these commitments and with these efforts, the water governance structure has been

enhanced and the water governing processes made more efficient in Samoa.

Nonetheless, much remains to be improved. For instance, the Water Resources Division of the MNRE

still reports lack of access to physical sites for evaluation and difficulty in receiving data from the SWA.

The continued need for improvements, as well as their limits and challenges, have been recognized by

the Samoan national authorities and reflected through important strategy documents. The Strategy for the

Development of Samoa (2012-2016) and the National Environment and Development Sector Plan

(NESP, 2013-2016), where water-related plans figure in prominently, are good examples of efforts to

address these problems, but some of their set objectives still must be translated into actions.

14

Government of Samoa (Ministry of Natural Resources and Environment), 2012b. Water for Life: Water & Sanitation

Sector Plan 2012-2016, Apia, GoS.

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Progress has also been made in the area of public awareness. Although hard to quantify, the Samoan

authorities have claimed a general positive evolution regarding the population’s perception of water.

Water seems no longer viewed as an unlimited gift but as it is: a threatened and vulnerable resource

(Government of Samoa, 2010). In reaching this conclusion, the MNRE continues to engage in

awareness-raising work, with a special emphasis on water conservation. Water-related issues benefit

from significant media exposure, including appearance in recurrent TV shows, radio talks, and

newspaper articles. Regular consultations with communities are also taking place, focused on

prevention and knowledge sharing about existing policy and recent regulations. In addition, community

engagement is strengthened through occasional programmes (e.g. river cleanup campaigns) and the

World Water Day commemoration. These efforts have resulted in substantial achievements, such as the

purchase by the MNRE of 485 hectares of land from the Samoan Catholic Church Land Board (CCLB) to

protect the Gasegase watershed, which supplies part of the water that flows to Apia (GEF Pacific IWRM

Project, 2013).

While awareness of water challenges among the public and decision makers has grown, the threat of

salinization of groundwater and coastal springs remains largely underestimated. Two explanations can be

proposed to explain this exception. First, the public recognition of groundwater as a vulnerable resource

appears low. The rising number of requests to drill boreholes, despite the existence of unused ones, and

the growing interest in exporting water overseas demonstrates this lack of understanding. Second,

saltwater intrusion, while acknowledged, does not constitute an issue of high importance in terms of

government priorities15

.

A complex phenomenon with profound implications

Due to both human and natural climate driving forces (as seen in Figure 2), saltwater intrusion is a

growing hurdle to Samoa’s sustainable use of water resources and development. However the influence

of saltwater intrusions on coastal springs and on groundwater is highly variable and the severity of the

15

None of the governmental actors we have met have claimed that saltwater intrusion was a prominent challenge to secure water in Samoa.

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problem is not consistently spread throughout the country. The extent of intrusion impact depends on a

locality’s natural characteristics and the type of water (surface or groundwater) used by communities

around the islands.

Many low-lying coastal villages mainly use coastal spring’s water for cooking and bathing purposes,

although it’s commonly consumed as a drinking alternative during times of water shortages. With further

sea level rise, the coastal springs will become more susceptible to saline intrusion, even during low tides,

making the population more vulnerable.

For example, in Saoluafata, a village located at the East of the capital Apia, coastal springs have become

saline and unsafe for consumption. Due to lack of assessment, the exact cause of the saltwater intrusion

remains uncertain. Local people argue that it results from a stronger seawater flow penetrating further into

the river flow (Government of Samoa, 2006); however it could also result from a seepage of seawater in

the shallow freshwater lens. While Saoluafata might be an extreme case, it is worth noting that seawater

intrusion is still a constant problem for many coastal springs in the country, especially during high tide.

Additionally, incidents of freshwater becoming brackish or saline have been reported in groundwater

reserves, especially in the northwest part of the island Savai’i, one of the driest parts of the country (see

Figure 3 and 4).

Figure 3: Auala Borehole Salinity16. Source: SWA, 2014

16

The world health organization (WHO) has set the acceptable limit for salinity to 250mg/l, although the organization has not established any health-based guidelines.

0

200

400

600

800

2006 2007 2008 2009 2010 2011 2012 2013 2014

Sa

lin

ity

(m

g/l

)

Years

Auala Borehole Salinity

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It is of particular concern knowing that saltwater intrusion has already led to the abandonment of many

production boreholes in the past in this area (Government of Samoa, 2012b). Salt pollution here is likely a

direct consequence of human pressures (i.e. the over abstraction of the boreholes) rather than resulting

solely from the effects of climate change and variability. One production borehole has been recently

drilled in the area to supply local water consumption, succeeding to those that were previously

abandoned just close-by. Saltwater intrusion might have had played a role in the decision although their

abandonment remain unclear. However, extracting water from the nearby borehole represents only a

short-term solution.

The issues of management and monitoring in the northwest part of Savai’i seems to suggest a very

different problem than the climate related challenges faced by the Saoluafata village (in Upolu)

demonstrating the pervasive and dynamic nature of saltwater intrusion issues. As indicated in Figure 4

and as previously mentioned, saltwater intrusion cases tend to differ from one location to the other in

Samoa. In Upolu, inflows of saline waters are sporadic and result from likely climate causes. In contrast,

Savai’i cases are concentrated in the northwest part and likely stem from human causes.

Figure 4: Reported saltwater intrusion cases in Samoa. Source: Authors (on Google maps)

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Safe and clean water is “essential for the enjoyment of life and of all human rights”17

. By turning the

freshwater brackish and unsafe for consumption, saltwater intrusion represents a threat to the very

source of the well being of people and society. The increased salinization of some coastal springs and

groundwater reserves is detrimental to a wide range of essential human activities. In general, the rise of

salinity level negatively affects fertile soils and crop yields. In this respect, Samoan authorities

acknowledge that sea level rise is one of the “key challenges associated with climate change, which will

increase the vulnerability of Samoa’s agriculture sector” (Government of Samoa, 2010). Yet, it should be

noted that most of the Samoan agriculture lands are located further inland and thus less likely to be

threatened by saline intrusion than on one of small atoll countries.

Saltwater intrusion also puts public health at risk. The likely impacts on agriculture may result in a lack of

affordable, nutritious and healthy food, which can weaken communities’ health, making people less

resilient and more vulnerable to diseases, especially to obesity-related ones. More directly, saline water

consumption can also lead to hypertension diseases (IPCCWGII, 2014). Additionally, the distribution of

the mosquito Aedes Polynesiensis, the vector for dengue fever, could be affected due to sea level rise

(Government of Samoa, 2010).

Current state of groundwater assessment and monitoring

Samoa is clearly facing a lack of water data and statistics, particularly in the groundwater sector. The

country has no groundwater profile and the Water Resource Division of the MNRE has monitored only 14

out of around 60 existing production boreholes. There is a growing concern and a profound uncertainty

regarding the state of groundwater in Samoa, particularly in light of the increasing requests for rights to

drill groundwater boreholes.

17

General Assembly resolution 64/292, the human right to water and sanitation, A/RES/64/292, 28 July 2010.

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Figure 5: Boreholes in Upolu. Source: Samoan Water Authority, 2014

Figure 6: Boreholes in Savai’i. Source: Samoa Water Authority, 2014

So far, few measures have been conceived to address the problem. The Water for Life 2012-2016 reports

slight progress in groundwater monitoring but further assessments of groundwater and surface water is

still a pressing need, as highlighted in the NESP 2013-2016. To respond effectively and efficiently to the

deficit of information on how the intrusions appeared and what their consequences are, human and

financial resources need to be enhanced in Samoa. Currently, the authorities are struggling to develop

and retain a sustainable level of hydrological technical and management capacity because of a high

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turnover of specialized staff and lack of applicants in the desired field: while advertising for a hydrology

specialist, most of the candidates received by the MNRE had a sociology expertise profile. B

ox 1

Data and monitoring to enhance resilience in Marshall Islands

Small and low-lying islands usually obtain their freshwater from rainwater catchments and thin, limited groundwater lenses. Due to these characteristics, they are especially vulnerable to saltwater intrusion that can result from both human and climate causes. The risk of saline contamination of the water resource is especially high during periods of drought, since groundwater withdrawals sharply increase to alleviate water shortages during those times.

Majuro Atoll (Republic of Marshall Islands) experienced such a scenario during El Niño 97-98, an event that wreaked havoc in the whole Pacific. To counteract the drought and the freshwater shortage, the daily groundwater withdrawals nearly tripled. Fortunately, in cooperation with the US Geological Survey, the Marshall Islands authorities have installed boreholes to monitor the status of the shallow freshwater lens to detect unsustainable pumping rates, which would have directly led to saltwater intrusion and endangered crops.

Having more data for analysis has undoubtedly improved the overall water management and decision-making process. The Majuro case highlights in an explicit and unequivocal way that assessment and monitoring are essential tools for water security, by enhancing the ability of authorities and the population to respond, mitigate and adapt to potential similar situations.

Inspired by the case study: “Managing vulnerable water resources in atoll nations” written by Stephen Anthony for PIRCA, 2012, Climate change and Pacific Islands: Indicators and impacts.

Conclusion

Ensuring quality and secure water resources are a critical development issue. It is an essential catalyst

for improving agriculture, health, education and sustainable development in general. Consequently,

saltwater intrusion, both from its climate and human causes, has to be regarded as a priority and properly

documented.

Pacific SIDS governments have repeatedly recognized this key impediment but research remains

incomplete and available information is lacking. In addition, Pacific SIDS are, in most cases, unable to

draw on an efficient institutional management and governance framework for water resources. In the

context of a highly complex scheme where traditional and legal structures are intertwined, official entities

have difficulty conducting reforms that can keep pace with the evolutions mentioned hereinabove. Facing

limited data and fragmented water governance, it is not only the decision-making process that is hindered

in SIDS but also the sustainable development perspectives that are restricted.

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Samoa is experiencing the same water challenges as other countries in the Pacific region. To respond to

these issues, the integrated water management and governance framework have been significantly

improved. However, the specialized human resource shortages and lack of data have been a

considerable stumbling block to the analysis of surface and groundwater related issues in Samoa.

Saltwater intrusion, an emerging threat in areas of Samoa, illustrates this observation. Though it has been

broadly acknowledged, as seen in national communications on climate change, information on the issue

remains basic, limited and patchy. Although of paramount importance and a prerequisite to any practical,

efficient and lasting solution towards the sustainable use of water, the lack of assessment and systematic

groundwater monitoring remains one of the main hurdles to overcome in obtaining water security and

engaging in sustainable development. With limited technical resources, the national authorities are

presently unable to address and respond effectively and efficiently to the increasing challenge of

saltwater intrusion. Key recommendations are:

The data gap needs to be addressed and information on more boreholes and coastal springs ascertained

in order to have a reliable and detailed assessment of the country’s current vulnerability to saline

intrusion.

There is no known integrated water analysis and projection in Samoa. This significant constraint is a key

element to be addressed to drive the water sector evaluation, planning and adaptation forward.

The tangible cooperation and collaboration between the national actors dealing with water should be

extended and deepen. Particular emphasis should be given to knowledge sharing between the Water

Resources Division of the MNRE and the SWA. Combined research between the Water Resources

Division and the meteorological services should also be encouraged.

The current commitments set in the SDS and the NESP need to be further translated into actions and the

legislation related to water needs to be better enforced. This specially includes supporting training and

capacity building related to groundwater assessment and management, while sustaining national public

awareness campaigns.

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These four key recommendations are important requirements for carrying on the achievements related to

drinking water coverage in Samoa18

. Human rights, economic aspirations and the well being of society

are at stake. As such, these guidelines represent a necessity for Samoa and the Pacific, for its population

today and tomorrow in proceeding towards the post-2015 agenda.

Biographical note

Denis Chang Seng is the Programme Specialist for Natural Sciences at UNESCO Apia, Office for the

Pacific States. Leo Berthe is assisting Dr Chang Seng work and research while finishing his Master

Degree in International Relations and Development. Lameko Asora is the Principal Officer of Hydrology

for the Water Resources Division of the Ministry of Natural Resources and Environment of Samoa.

Acknowledgments

This case study is the result of a research work led by the Science programme of the UNESCO Apia,

Office for the Pacific States. However, this production would not have been the same without the support

and advice of different people and institutions.

We want to warmly thank every individual and division from the Ministry of Natural Resources and

Environment (MNRE) of Samoa that gave their time to help us in this study. We would like to

acknowledge their key role in dealing with problem of scarcity of information by providing tangible facts

and field observations to this case study. In this regard, particular thanks go to the Water Resources

Division and to the Water Sector Coordination Unit, which have made their expertise available for us.

We are also very grateful for the guidance and advice of Engin Koncagul, programme officer at the United

Nations World Water Assessment Programme.

At last, we wish to thank Mikia Weidenbach for her language editing and constructive review.

18

According to the UNICEF/WHO Joint Monitoring Programme for water supply and sanitation, Samoa has met the MDG on drinking water source. In 2012, 12% of the population gains access to improved water-drinking compare to 2000. Nonetheless, considerable efforts have still to be done to meliorate the water quality, which remain of poor quality in general (Government of Samoa, 2012b).

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