POST-TSUNAMI RESEARCH INITIATIVES IN THE
COASTAL ZONE OF
SRI LANKA
Ana Gunatilaka
Geological
Consultant, National Science Foundation of
The 2004 December megatsunami that originated in the Sunda
Trench region is probably the greatest ever in modern human history. In
During the past three months,
several Sri Lankan research teams have been gathering data around the coast on
various aspects of this tsunami, based on the guidelines given by the
Intergovernmental Oceanographic Union (IOU). Data on inundation distances,
maximum run-up heights, maximum tsunami heights, standing water levels,
eye-witness accounts etc. have been collected from over 200 localities and is
still continuing. The initial inundation mapping surveys indicate quite
dramatically that the above tsunami parameters are highly variable even within
very short distances (<100 m), indicating that several variable factors have
contributed to the inundation pattern at a given locality. The presence or
absence of mangroves, fringing coral reefs, nearshore
bathymetry, angle and direction of wave approach, shape of the coastline,
artificial coastal boulder barriers, coastal dune complexes, topographic
profiles and gradients from coast to inland are among them. Such detail is
required by the government of
Perhaps the most damaging impact of the tsunami is on the groundwater table in the coastal zone. Over 50,000 drinking water wells abandoned, sewerage systems damaged, with cross-contamination of the water table. Presently, almost a million people in the coastal areas are being supplied with drinking water on a daily basis, at tremendous cost to the state, NGOs and local authorities. Water quality was already poor even before the tsunami. Now it is critical. Further, unscientific cleaning activity by continuous pumping by individuals is only exacerbating the situation, with further salt intrusion into the wells. The groundwater problem will be the most challenging aspect to the authorities and it may take a very long time to restore normalcy. The most highly focused research efforts are on groundwater, with three teams operating in different areas of the coastal zone. Hopefully, the data gathered will lead to a permanent groundwater monitoring and Integrated Water Management Plan for the affected zone. The opportunities for research on groundwater modeling will be an added bonus. Water that was freely available by nature has now become a very precious commodity.
Two research teams are studying
sediment profiles along selected traverses (initially 20 traverses are
envisaged) and encompassing the wide inundation variability seen. The purpose
of this study is to correlate the sediment sequences and their depositional
features with the combined flow characteristics of a tsunami wave as it moves
inland and withdraws – data that will be useful in studying paleo-
megatsunamis. Initial coastal modeling studies
indicate that a bay and headland or promontory is the most devastating
geomorphic combination during a tsunami. The bay creating a
funnel-like effect and the headland a wrap-around effect for the tsunami wave,
as happened in the port city of
It became quite obvious that construction quality in the coastal zone is much to be desired. Foundations were not deep or reinforced and were on loose sand. Houses toppled as the debris-charged wave created a path of destruction inland. There are some indications that the geotechnical properties of the soils in the coastal zones may have been altered. This is also being investigated. Obviously, a new building code needs to be strictly enforced. Much of this research initiative has been generously funded by the National Science Foundation of Sri Lanka.
Generally, the east coast of
Ana Gunatilaka Ph.D.
National Science Foundation,
47/5,
Groundwater Conditions
in the Coastal Region of
Abstract
A.P.G.R.L. Perera, Hydrogeologist,
Water
Resources Board, 2 A, Gregory’s Avenue,
Seven main types of
groundwater aquifers have been identified and characterized in
1. Shallow
Karst Limestone Aquifer of
2. Deep
Confined Aquifer
3. Coastal
Sand Aquifer
4. Alluvial
Aquifer
5. South
Western Lateritic Aquifer
The shallow karstic aquifers are
mainly confined to
Deep confined aquifers are found in the coastal regions of the north
and northwest extending from Puttalam to
Coastal sand aquifers -3 types have been recognized and characterized;
(a). shallow aquifers on coastal spits and bars in the
northwest are found in Kalpitiya peninsula and
Groundwater in these aquifers
gets collected in the forms of fresh water ‘lenses’ above denser saline water.
Coastal sand aquifer regions of
One of the largest carriers of
groundwater is river alluvium. The flood plains of Rivers such as Kelani Ganga and Deduru-oya have broad and deep alluvial beds in their lower
reaches in the coastal region to West.
Laterite aquifers
are found in the coastal region of southwest
The remaining hard rock regions
of
More than 90% of the total
requirement of water in cities such as Puttalam, Mannar Jaffna and Batticaloa in the coastal region is used groundwater.
Biological contamination of groundwater is a common problem in all the coastal
regions.
HYDROGEOLOGY OF THE COASTAL
AREAS OF
H.A.Dharmagunawardhane , Department of Geology,
Occurrence and distribution of ground water in the
coastal areas of
Although there are complex geological and hydrogeological conditions, prevailing locally, the coastal belt can broadly be divided into three
aquifer regimes,
a) Northern and north western limestone aquifers
b) Quaternary unconsolidated sandy aquifers
c) Combined rigolith and
fissured crystalline aquifers
Northern and north western limestone
aquifers
Highly Karstic and permeable Miocene
limestone aquifers are present along the Northern and North western coastal
belt from Puttalam through
High nitrate in groundwater in unconfined aquifer
areas arising from intense agricultural practices and High chloride associated with saline water intrusion due to
uncontrolled groundwater
abstraction are common water quality problems in the
sedimentary aquifer system.
Quaternary unconsolidated sandy aquifers
Wind blown accumulations of
recent sands forming dunes occur along almost one fifth of the coast line of
Sri Lanka These together with Pleistocene and Holocene deposits of sand has created sufficiently thick (up to
25m) local and discontinuous highly
productive aquifers in certain areas. This type of aquifers are found along most parts of the eastern
coast from Hambanthota to Mullathivu
and in the western coast from Negombo to Palavi. The transmissivites of these aquifers are in the order of 2500m2/day.Good
quality groundwater occurs in these aquifers and the groundwater table is
present at a depth between 2 to 6m from the surface. In these aquifers, fresh water floats on the
saline water at fresh water saline water interface on the seaward side of the
aquifers. Excessive pumping often causes saline water intrusion. These
unconfined (and occasionally semiconfined) aquifers
are highly vulnerable to contamination where direct infiltration of
contaminants is common from agricultural activities and onsite waste disposal
in these areas.
Combined residual/rigolith
and fissured
crystalline aquifers
The
slightly elevated coastal area from
Alluvial formations that occur in the low lying marshy
lands, wetlands and estuaries have very shallow groundwater levels but often
contain brackish water unsuitable for drinking and domestic purposes.
As indicated above, the coastal aquifers in
Pre and Post Tsunami Effects on Agricultural
Lands of
Ranjith. B.
Mapa,
Faculty of
Agriculture,
W.M.A.D.B. Wickramasinghe,
D.N. Sirisena
Rice Research and
K.M.A. Kendaragama
ABSTRACT
Due to the
Tsunami disaster, which took place on 26th December 2004, lands along about
1200 km of the costal belt of
For this study, Amapara district in the East of Sri Lanka which was extensively damaged by the Tsunami was selected. This area is called the rice bowl of the country giving high yields amounting to 6 tons per ha. Electrical conductivity, which is an indicator of soil salinity, was measured in effected lowland rice fields as well as in cultivated highlands. Salinity of adjacent unaffected areas were measured and taken as pre-Tsunami values. Nindavur area was selected to assess the damage to rice fields while Vinaygapurum in Thrukkovil where tomato, chillies, cowpea and eggplants were grown extensively was selected to assess the damage to the highlands. Electrical conductivity (EC) was measured in the saturated soil paste from 0-5, 5-15 and 15-30 cm depths at 200, 400 and 900 meters from the sea after 18 days of the disaster. This was followed by measurements after 4.5 months and 8 months at the same sites in the rice fields in Nindavur.
The measurements after 18 days of Tsunami showed that the EC values of the saturated paste of the effected areas were highest in the rice fields nearest to sea (200 m), showing 6.12 and 2.94 dS/m respectively at surface and subsurface depths. At a distance of 900m the EC values decreased to 0.85 and 1.28 dS/m in surface and subsurface respectively. The standing water in some depressions in the rice fields showed an EC value high as 11.46 and 5.84 dS/m at 200 and 400 m away from the sea. In the unaffected rice lands the EC was low as 0.07 dS/m.
The next crop of rice was sawn after 4 months of Tsunami. In the same area where the sea water was stagnant EC values decreased only to 3.2 dS/m and the seed germination was very low resulting in a poor stand of crop. Even if rice varieties resistant to salinity can tolerate EC values higher than 4 dS/m the variety grown (BG 94-2) can withstand only lower salinity levels. Due to ploughing at the same depth repeatedly and puddling, a hard pan is formed in lowland rice fields around 15 to 20 cm depth, which restrict deep percolation. In fields where surface drainage was satisfactory, most of the salts got washed way reclaiming the land naturally. The EC values of these lands decreased to 1.7 dS/m after 4 months of Tsunami and a satisfactory stand of crop was observed. The rice crop is irrigated from Senanayaka tank and the irrigation water showed an EC value of 0.18 dS/m. The drainage facilities of some rice fields were improved with the assistance provided by a private company and the drainage water showed an EC value of 2.84 dS/m. At the same time well water in the same area showed a higher EC value of 3.63 dS/m.
At the harvesting time of the crop (8 months after Tsunami) the EC values of the same field with stagnant water showed an EC of 1.06 dS/m in surface soil which increased to 1.85 dS/m at 15/30 cm depth. This indicates that salinity increased with depth due to leaching but stopped at the hard pan. In this land, a thin hard crust was formed upon drying during harvest time indicating soil dispersion due to higher Na content. Where surface drainage was satisfactory the EC values were low as 0.02 dS/m in the surface and to 0.03 dS/m in the subsurface. In the unaffected areas (control) EC values were low as 0.03 and 0.04 dS/m respectively in surface and subsurface soils.
In the highlands the highest EC value measured after 18 days of Tsunami was 0.60 dS/m in the sub soil at 400 m away from sea. Even in the highlands, where water logged conditions prevailed the EC was higher as 3.5 dS/m and the well water showed an EC values of 3.14 dS/m. The highlands are well drained and therefore salinity is easily leached to deeper layers.
These data clearly demonstrate that in certain pockets of land, especially in rice fields where the drainage is poor, the salinity still prevails at high levels affecting the rice crop, even after 8 months of Tsunami. There is a need to identify the land areas where salinity still remains at high levels and improve surface drainage for the farmers to cultivate them even in future seasons. In this exercise priority should be given to lowland rice lands than for highlands.
Synopsis of Post-Tsunami Rapid
Environmental Assessments in
Ministry of Environment and Natural Resources
13th June 2005
1. Scope of the assessments
In an immediate response to the tsunami, the
Minister of Environment and Natural Resources, Hon. A. H. M. Fowzie, took steps to carry out a Rapid Environmental
Assessment (REA) of the tsunami-affected areas, in close cooperation with the
Central Environmental Authority (CEA), and with the assistance and support of
the United Nations Environment Programme (UNEP). The REA was undertaken by scientists from Amparai,
The ‘green’ assessment involved describing, at one-km intervals over more than 800 km of affected coastline, transects perpendicular to the shore and running inland from the high tide line. Data were collected on vulnerability, physical, ecological and social damage, land use, constraints on and options for land use, and on the precise pattern of tsunami inundation. All observations were georeferenced digitally. These profiles provided a significant sample of observation points and a set of locations where the complex interaction of the tsunami with topography, ecosystems and human settlements could be analysed and understood. Each was also an observation point for overlapping descriptions of the surrounding area, yielding continuous coverage of the affected coast.
The ‘brown’ assessment concentrated on contamination at over 750 sites where particular risks were known to exist because the tsunami affected facilities for storage or processing of potentially hazardous materials. These included both established solid waste dumps and new ones used to dispose of tsunami debris, as well as storage and processing facilities associated with the commercial, health, security, transport, tourism, agriculture, fisheries, mining and other sectors. Each site was assessed for type, scope and intensity of pollution, looking at faecal, oil and toxic contamination, visual, air, odour and thermal pollution, disease risks and salinization. Samples of water and soil were collected wherever necessary and analysed chemically. Sites were scored for the severity of impact and conclusions drawn on the urgency and feasibility of mitigation in terms of either short-term, medium-term or long-term projects.
This document is a synopsis of the main findings of the
‘green’ and ‘brown’ assessments, which also takes into account findings by
other national institutions (CCD, DWLC,
2. Summary of assessment findings
a) Variation in depth of penetration.
The tsunami impacted the eastern coastline of
b) Debris and solid waste.
Well over 500 million kg of rubble were created by the tsunami and are still posing an enormous challenge to the solid waste management system. Debris and marine sand, whether deposited by the tsunami or by subsequent clean-up operations, block drainage channels in many areas, posing an acute risk of water-logging and loss of agricultural land, as well as increased mosquito-borne disease.
c) Salinization of drinking water wells.
This has affected large areas and rendered more than 15,000 wells unusable, greatly reducing water supplies. Over-pumping of wells in an attempt to clean contaminated or saline water and restore fresh-water supplies has often encouraged salt-intrusion, which has done more harm than good. Existing mobile water treatment units in this respect need scrutiny.
d) Contamination
of water bodies.
Several coastal water bodies have been contaminated with
salt-water, debris, floating material, faecal matter
and black sediments, etc. Karagan lewaya,
Hambantota,
e) Resettlement and reconstruction.
These activities are placing a huge burden on natural
resources, especially through the location of new settlements in or near
protected areas and other ecologically sensitive locations, and increased
demand for sand and wood for reconstruction and firewood for brick-making. Faecal contamination of ground water has become a major
issue in some of the tsunami-affected areas, and further resettlements could
worsen the situation. Without careful
management, these activities have the potential to cause more irreversible
damage to
f) Damage to marine ecosystems.
These showed a variety of impacts; shallow fringing coral reefs were damaged mechanically, with breakage of branching corals and dislodging of boulder corals, with some smothering by debris carried by backwash; intact coral reefs acted as buffers, but these were few because of pre-tsunami damage from mining, blast-fishing and bleaching.
g) Damage to shoreline ecosystems.
Estuaries often acted as channels of entry for the tsunami, facilitating damage and salt intrusion far inland. Front-line mangroves were badly damaged, while deeper mangroves were left intact and dense mangroves converted the wave into a flood. Lagoons absorbed tsunami energy, but in doing so lost seasonal sand barriers, their banks were scoured, and mangroves at their entrances were dislodged, but they were otherwise little affected and/or recovered quickly (apart from litter and debris pollution, and some cases of blocked water flow causing stagnation). Large, vegetated sand dunes stopped tsunami intrusion. Beaches were eroded and scoured, losing width and height, mainly from tsunami back-wash. There is much debris on most beaches, including unexploded ordnance in some areas.
h) Damage to inland ecosystems.
There was severe damage in near-shore areas, including to seashore Pandanus and creeper vegetation, and inland palmyra trees, with near-shore coconuts less affected as were inland economic trees. Casuarina plantations proved vulnerable to tsunami damage and by themselves had little protective value, though in places they helped stabilise sand dunes which themselves moderated the tsunami. Alien invasive species have been spread by the tsunami into new areas.
3. Summary of recommendations
a) Urgent interventions in particular sectors.
· Debris management - mobilise local government and communities to undertake immediate sorting and safe and environmentally-responsible disposal of debris on a ‘cash-for-work’ basis at the local level under the direction and guidance of the CEA.
· Environmental contamination - manage pollution hotspots associated with solid waste dumping and sludge disposal; sample and test marine sludge deposits for possible heavy metals and other persistent pollutants, and remove and safely dispose as appropriate.
· Rehabilitation of natural water bodies - remove debris and sludge, release stagnant, anoxic and contaminated water, and restore pre-tsunami ecological conditions to the extent possible.
· Restoration of land drainage - clear sand and debris from drainage channels, in order to prevent the loss of productive land by water-logging, and the increased transmission of mosquito-borne diseases.
· Sustainable recovery and reconstruction of water supplies - train all staff who manage water treatment and pumping units to maximise the sustainable rate of recovery of safe water supplies and to prevent over-pumping and irreversible salinisation of wells and ground water; invest in the provision of drinking water supply in many affected areas.
·
Sand mining and nourishment- identify
areas where the landward sides of large sand dunes could be harvested for sand,
or wind-blown sand trapped in commercial quantities, without affecting the
dunes’ ability to protect the coast; areas that need nourishment must also be
identified and sand pumping carried out as needed.
·
Ecosystem management – work with NGOs,
local community and other responsible elements to rehabilitate damaged
ecosystems with priority to Special Area Management (SAM) sites.
b) Urgent
interventions at specific sites.
· Clearing debris, and in places unexploded ordnance from beaches, seashores, near-shore sea beds and coral reefs.
· Restoring access channels for fishing boats.
· Replacing and/or relocating safe anchorages.
· Identifying sites for properly-regulated sand mining.
· Identifying sites that need proper water supply and sanitation facilities.
· Regenerating and stabilizing sand dunes and the banks of drainage channels.
· Removing sand and debris from drainage pathways and farmland.
· Assessing and restoring ground-water quality.
· Identifying land suitable for resettlement, with special attention to freshwater supply, drainage, fishery livelihoods and tenure/resource conflicts.
· Restoring original ecosystems in water bodies and SAM sites.
c) Urgent
strategic interventions.
· Coordinating post-tsunami investment through a standing committee co-chaired by MENR, CEA and TAFREN, and expert/donor round-tables as needed, to ensure that environmental concerns are fully integrated in all decisions on national reconstruction, and to coordinate country-driven implementation of all relevant government recommendations.
· Strengthening national policy on the management of critical environmental issues through joint MENR-CEA-TAFREN leadership, including policy on the environmentally-responsible disposal of debris and solid wastes, the extraction and sustainable supply of safe drinking water, the restoration of effective drainage to farmlands and urban areas, and the prevention of deforestation resulting from construction and resettlement. The policy framework should be used to develop mandatory guidelines to ensure uniform practice.
· Enhancing the role of MENR in national reconstruction planning, by resourcing it to allow the participation of its officials and/or consultants in all relevant decisions.
· Building institutional capacity for environmental management through an appropriate combination of training, addition of expert staff, resourcing to allow the use of national consultants, provision of appropriate equipment, hardware and software, and resourcing to support field work, data and sample analysis and reporting.
· Building capacity for public participation in ecosystem restoration by encouraging and enabling local authorities to develop and implement integrated local plans at the community, divisional and provincial levels that incorporate options for restoring ecosystems known to help protect against environmental shocks (e.g. mangroves, dunes, reefs and wetlands) as well restoring home gardens, plantations, bunds, banks, channels and other features of livelihood significance that also help protect the environments where people live.
· Disseminating information by producing and distributing clear, simple, illustrated guidelines in appropriate languages, on how safely to classify, separate, compost, re-use, recycle and dispose of solid waste and debris, how to design and construct improved housing and sanitation using safe materials, and how to identify and correct environmental problems such as blocked land drainage, salinisation, and the spread of alien invasive species.
· Mapping of coastal zone terrain up to the 10 m contour, to support priority setting for coastal defence investments.
·
Encouraging
and enabling regional collaboration, by ensuring that
· Building consensus on national priorities through a national round-table discussion on lessons learned from the tsunami, and national priorities for restoration and development in the coastal zone.
4. The path ahead
The above-mentioned body of
recommendations and potential projects has emerged based on the findings of the
REA. A Development Forum held in
· Establish a high-level Multi-stakeholder Platform, comprising MENR, TAFREN, CEA, UDA and other key institutions, to coordinate and direct environmental inputs to the implementation of the PTRR strategy.
· Establish a Helpdesk in Colombo and a network of District Environmental Helpdesks, to facilitate rapid responses to problems experienced at the local level in the implementation of the environmental component of the PTRR strategy.
· Hold meetings of national, provincial and local governmental and non-governmental institutions:
o to develop a comprehensive plan of action for environmental remediation and integration of environmental considerations in the implementation of the national reconstruction and development programme;
o to align environmental needs with donor assistance; and
o to make institutional arrangements to prevent the duplication of effort, ensure coordinated environmental action at all levels, and arrange for monitoring and further support for implementation.
|
Annex 1: Summary of proposed urgent
interventions |
|||
|
Project
theme |
Target |
Proposed
intervention and location |
Indicative
budget (US$) |
|
1. Managing debris and waste |
Tsunami-affected
areas |
Mobilise local government and communities to undertake
immediate sorting and safe and environmentally-responsible disposal of debris
and solid wastes on a ‘cash-for-work’ basis at the local level with the
direction and guidance of CEA. |
2,000,000 |
|
2. Assessing and remediating
environmental contamination |
Component 1: Tsunami-affected water
bodies in |
Component 1: Restore affected lagoons and estuaries
(e.g. Karagan lewaya, Hambantota, |
2,000,000 |
|
|
Component 2: Abandoned and active
mineral pits. |
Component 2: Remedy pollution
hotspots associated with solid waste dumping and sludge disposal (e.g. at Thelwatta, Akurala, Habaraduwa and Ambalangoda). |
500,000 |
|
|
Component 3: Tsunami-affected areas
in |
Component 3: Share information among
countries concerning the sampling and testing of marine sludge for persistent
pollutants, and its removal and safe disposal. |
75,000 |
|
|
Component 4: Tsunami-affected fishery
harbours |
Component 4: Clean, rehabilitate,
restore or reconstruct fishery harbours as needed
(e.g. Panadura, Beruwela,
Hikkaduwa, Tangalle, Hambantota, Kirinda harbours and Arugam Bay, Kalladi Beach, Vallachchanai
lagoon anchorages); correct sanitation and waste management issues. |
2,500,000 |
|
3. Rehabilitating ecosystems |
Component 1: Rehabilitation of SAM
sites |
Component 1: Rehabilitate SAM sites
with removal of debris and sludge, dilution of stagnant, anoxic and
contaminated water, and restoration of pre-tsunami ecological conditions. |
200,000 |
|
|
Component 2: Rehabilitation of
Protected Areas |
Component 2: Restore natural
vegetation and eliminate alien species, restore damaged sand dunes, clear
debris (e.g. Yala, Bundala). |
100,000 |
|
|
Component 3: Rehabilitation of
wetlands |
Component 3: Restore mangroves in the
first 300 metres on both sides of the Odu lagoon, and on both sides of the Batticaloa-Vaharai
road, where previously cleared for security reasons. |
500,000 |
|
4. Restoring land drainage |
Tsunami-affected
areas |
Clear
sand and debris from drainage channels to prevent water-logging and impacts
on farming and public health. Make new drainage as appropriate so as to
minimize the water –logging capacities |
300,000 |
|
5. Water supply and sanitation |
Component 1: Tsunami-affected areas |
Component 1: Provision of water
supply. Reconstruct new water supply
schemes and sanitation facilities |
200,000,000 |
|
|
Component 2: Tsunami-affected areas |
Component 2: Provision of safe potable
water supply from existing mobile units during transition. Train all staff who manage
water treatment and pumping units to maximise the
sustainable rate of recovery of safe water supplies and to prevent
over-pumping and irreversible salinisation of wells
and ground water. |
500,000 |
|
|
Component 3: Tsunami-affected areas |
Component 3: Rehabilitation of
sanitary facilities in temporary welfare camps during transition. |
5,000,000 |
|
|
Component 4: Tsunami-affected areas. |
Component 4: Provision of sanitary
facilities for new settlements. |
94,500,000 |
|
6. Sustainable sourcing of sand |
Nationwide |
Identify
areas where the landward sides of large sand-dune systems could be harvested
for sand, or wind-blown sand could be trapped in commercial
quantities, without affecting the dunes’ ability to protect the coast. |
30,000 |
|
7. Policy development and implementation |
Component 1: Nationwide |
Component 1: MENR, CEA & TAFREN,
supported by expert/donor round-tables as needed, cooperate to ensure that
environmental concerns are fully integrated in all decisions on national
reconstruction, and to coordinate country-driven implementation of all
relevant government recommendations. |
40,000 |
|
|
Component 2: Nationwide |
Component 2: MENR, CEA & TAFREN
to develop an integrated national policy framework on the management of
critical environmental issues arising from the tsunami
(environmentally-responsible disposal of debris and solid wastes; extraction
and sustainable supply of safe drinking water; restoration of effective
drainage to farmlands and urban areas; prevention of deforestation resulting
from construction and resettlement).
Develop mandatory guidelines to ensure uniform best practice. |
60,000 |
|
|
Component 3: Nationwide |
Component 3: Enhancing the role of
MENR in national reconstruction planning. MENR to be resourced to allow
participation in all relevant decisions by MENR officials, by other
government officials with special knowledge acting on behalf of MENR, and/or
by MENR consultants from the Sri Lankan academic, business and other
communities |
50,000 |
|
8. Building capacity for environmental
management |
Nationwide |
Build
capacity of MENR and CEA to conduct EIA and establish monitoring procedures
prior to construction of new settlements and infrastructure, through
training, addition of expert staff, resourcing to
allow the use of national consultants, provision of appropriate equipment,
hardware and software, and resourcing to support
field work, data and sample analysis and reporting. |
200,000 |
|
9. Promoting public participation in ecosystem
restoration |
Pilot
Districts and Provinces |
Strengthen
local authorities through MPCLG to develop and implement integrated local plans
at the community, divisional and provincial levels that incorporate options
for restoring ecosystems known to help protect against environmental shocks
(e.g. mangroves, dunes, reefs and wetlands) and restoring home gardens,
plantations, bunds, banks, channels and other features of livelihood
significance and also help protect the environments where people live. |
200,000 |
|
10. Disseminating knowledge |
Nationwide |
Produce
and distribute simple, illustrated guides on how safely to handle, classify and
process solid waste and debris, how to design and build improved housing and
sanitation using safe materials, and how to identify and correct
environmental problems such as blocked land drainage, salinisation,
and the spread of alien invasive species. |
10,000 |
|
11. Mapping coastal zone terrain |
Coastal
zone |
Detailed
mapping of coastal zone terrain (up to about the 10 m contour) to support
priority setting for coastal defence activities. |
3,000,000 |
|
13. Promoting regional collaboration |
|
Enable
|
150,000 |
|
14.
Building national consensus |
Nationwide |
National
round-table discussion on lessons learned from the tsunami and national
priorities for restoration and development in the coastal zone. |
100,000 |
|
|
|
Total
indicative budget |
312,015,000 |
Impact on drinking water supply & sanitation facilities and
rebuilding of the water & sanitation infrastructure
affected by the
Tsunami tidal waves
R. S. C. George
Deputy General
Manager (Corporate Planning)
National Water Supply
& Drainage Board
Abstract
The Tsunami tidal waves caused damage mainly to exposed
parts of water supply systems. Water
supply services were disrupted in the affected coastal areas owing to
this. Quick remedial action was
necessary to resume supply. Most of the
toilet structures were damaged in the affected areas. Septic tanks in the flooded areas were
full. Again immediate action was
necessary to repair the toilets and empty the septic tanks. Immediate relief activities had to be
provided in the affected areas. This
included water supply using bowsers; construction of
temporary toilet facilities or repair of existing toilets; enhancement of
facilities in temporary/ transit camps; emptying and cleaning of wells etc.
Some people went back to their damaged houses and their
water supply facility had to be restored.
Some of our customers were provided with alternate land and they had to
be provided with new connections free of charge. The land use planners identified resettlement
areas for the affected people. Water
supply facilities had to be extended to those areas. In certain areas this requires the
augmentation of the treatment works.
Meanwhile several donors pledged their support to assist
Tsunami Impacts on Shallow Groundwater and Associated Water
Supply on the East Coast of Sri Lanka
Karen G. Villholth,
Senior Researcher, Groundwater Specialist
Abstract
The major Tsunami of Dec. 26, 2004 that hit many South Asian
countries bordering the Bay of Bengal severely devastated the coastal regions
of
Pre
and Post Tsunami Effects on Vegetation of Coastal Areas
S.P. Nissanka
Department of Crop Science
Faculty of Agriculture
Abstract
The devastation and destruction
caused by the tsunami disaster is not only restricted to damaging human lives
and livelihoods but also collapsed the entire environmental, agricultural and
social setup of the coastal area of
Situation assessment results
reveled that 82% and 62% of the displaced people are in favor of moving out of
the proposed 100 m buffer zone in Hambantota and Amapara districts respectively. Furthermore, most of the people who wish to
move away from the buffer zone wanted to continue their authenticity in the
former lands. Regarding future
expectations of the affected community both at Hambantota
(85%) and Ampara (95%) districts, permanent residence
appeared to be the top priority. The job priority (livelihood) seems secondary.
It highlights the affected people’s desires on the rehabilitation programs.
Large stretches of coastal region inundated with saline seawater body up to a few kilometer to heights of about 10-30 m at certain places. Severity and the extent of the damages varied with the force of the tsunami waves, topography, land use pattern, vegetation types and the extent of damages caused to sand dunes and corral reef. In addition to the loss of thousands of human lives and properties, inundation of coast and deposition of saline sediments caused severe damages to natural habitats of terrestrial and wetlands, agricultural fields and plantations, and to soil and water bodies etc. Major terrestrial vegetation types come under the tsunami-affected regions are thorny forest/scrublands, sand dune vegetation, arid zone maritime grasslands/pasture, riverine forests, and semi evergreen forests. The major wetland types are the salt marsh, mangrove, brackish water lagoons, seashore, water hole/tanks, and streams.
It is estimated that the number of farming families affected by the Tsunami was 9048 and the total extent of damage to agricultural land is around 4200 -6000 ha. In most environmental surveys to date, damage to the natural ecosystems was categorized as slight or negligible in most instances except for few cases. Among the different land use systems, paddy farming was the hardest hit mono-crop, next to fruits and vegetables grown in home gardens. The total number of home garden units affected is estimated as 27,710. However, over 50% of the agricultural lands have been successfully replanted several weeks or months after the tsunami.
Study carryout by our team to investigate the impact of tsunami on vegetation and soil salinity developments (over 500 soil sampling sites) in the southern region of different land use types namely; urban and rural home-gardens, rice fields, coconut fields, and plantation and natural forest, revealed that salinity development is not a major problem across all land use types. Majority of the sites are having EC values lower than 4 dS/m. Few areas developed salinity, they are mostly sites where sea water was accumulated for longer period due to topographical setup. These sites may need restoration and recovery attention. However, these sites could be recovered faster if the drainage is improved. As an immediate measure especially for rice cultivation use of salinity tolerant varieties, irrigation and improved drainage facilities together with site-specific fertilization and organic matter may improve the productivity.
Mostly affected species in urban and rural home-gardens are the mango, banana, breadfruit, palmyrah, some citrus spp, sesbania etc. Coconut, woodapple, pomegranate, neem, casuarinas, gansuriya (Thespesia populnea), palu (Manilkara nhexandra) were some species that were not or least affected. Most of the species that were defoliated are recovering. Some species have shown bud breaking and production of fruits with high salt contents (Guava) showing stress adaptation mechanisms. Forested lands and Coconut fields are also having a similar trend. There were a few sites where salinity levels are higher than 4 dS/m (range of 4-10). The trend has been to have slightly higher EC near seashore and decline when moves towards countryside. Urban-homegardens were having soil EC levels well below 4 dS/m casing no real impact on vegetation.
Most of the pandanus and mangrove stands in beachfronts and lagoons were severely affected because these species were the first line of defense in many areas, which took over the full force of the waves. Seashore vegetation cover that consists of mainly creepers is reduced by about 75% in some locations. Debris, sands and sea mud deposited on maritime grasslands, salt marsh and agricultural lands and other land use types. Land use setups such as bunds, irrigation channels, and drainage systems have been badly blocked and destroyed. Massive erosion has occurred and debris left on agricultural fields especially on rice fields pose a problem as the large areas of land need to be cleaned which can be time consuming.
Tsunami waves have pushed seeds of
alien invasive species from their coasts farther inland especially in southern
region. In some areas, including important national parks, the wave has
encouraged the spread of alien invasive species, such as prickly pears (type of
cactus) and salt-tolerant mesquite (Prosopis),
which have become an invasive and severe threat to the natural vegetation in
the Bundala national park. They will definitely
spread in an unprecedented rate and become dominant posing a severe threat to
our natural ecosystems reducing faunal and floral diversity.
In some areas species like Trianthema (sarana), Solunum xanthocapum(elabatu), Avera spp (pala types) are thriving
well and spreading very rapidly.
Several studies
confirm of many signs of satisfactory recovery; trees knocked over by the
wave’s impact and inundated vegetations are regenerating, wildlife including
those of elephants and leopards is returning to damaged areas and beginning to
drink from ponds that had been contaminated with saltwater but are returning to
fresh water.
We
learned that the natural ecosystems and barriers such as coral reefs,
mangroves, other coastal vegetation and sea-grasses, and sand dunes which we
have so casually destroyed were the lifesavers capable of helping to defend our
homes, our loved ones and our livelihoods from this nature's more aggressive
acts. Several studies also confirm that in those areas with healthy coral reefs
and mangroves, the impacts of the devastating tsunami were significantly
reduced. Mangrove forests along shorelines are considered critical to halting
erosion, but much of growth has fallen victim in recent years to intense
coastal development.
Resettlement and reconstruction are now placing a huge burden on natural
resources, specially through the location of new
settlements in or near ecologically sensitive areas, and increased demand for
sand and wood for reconstruction and firewood for brick-making etc. It is
therefore vital, that during the reconstruction of shattered coastlines and
settlements, the environment is taken into account along with the economic and
social factors. If ad-hock, unplanned decisions are taken, it may cause more
irreversible damages to the environment than did the tsunami itself.
Tsunami affected many of natural and
agro-ecosystems by destroying natural habitats, vegetations in home gardens,
plantation crops and forest species and farm fields causing salinization
of soil, wells, ponds etc. So far, much of what is known about the
environmental damage of the tsunami comes from anecdotal or local
reports.