Transcript sharing experiences in design and implementation

SHARING EXPERIENCES IN
DESIGN AND IMPLEMENTATION
OF
CLIMATE CHANGE
ADAPTATION MEASURES
Lima, Peru, 22-23, January,
2009
Guyana Conservancy Adaptation Project
(Lionel Wordsworth)
Chief Executive Officer,
National Drainage And Irrigation Authority
Chairman,
East Demerara Water Conservancy Board
(Guyana)
Agenda
Country Profile
Overview of Guyana’s Drainage and
Irrigation System
Climate Change and Guyana
Guyana Floods in 2005
Initiatives towards adaptation/mitigation of
climate change.
Conservancy Adaptation Project
Guyana: Geographical Location
GUYANA
Venezuela
Suriname
Brazil
Country Profile
Land Mass:
83,000 Sq. Miles
Population:
750,000
Natural Rainforest:
61,776 Sq. Miles
Guyana Economy is well endowed with:
- Fertile agriculture lands;
- Available fresh water;
- Range of diversified mineral deposits
- Rich and exclusive economic fishery zone
OVERIEW OF GUYANA’S DRAINAGE AND IRRIGATION
SYSTEM
The D&I system has its origin during Guyana’s Dutch Colonial period
some 200 years ago an consist of an intricate network of drainage,
irrigation, sea and river defence infrastructure and this can be considered
the primary foundation for the country’s economy.
Some of our main physical infrastructure along the Coast of Guyana
includes 4 water conservancies, namely MMA, EDWC, BWC and Itirbisi
and the water storage and transport system to facilitate the Skeldon
Expansion Project, the Link Canal which is almost completed
The drainage system comprises of 136 drainage sluices along the sea coast
and our main river banks. This system allow drainage by gravity tidally,
and are augmented with 85 drainage pumps along the costal corridor.
The gravity drainage discharge window from low tide to mean tide is
shrinking due to sea level rise.
CHALLENGES
The rapid rate of siltation of
rivers and outfall channels
results in decrease efficiency in
gravity based drainage.
The most serious weatherrelated challenge affecting the
agriculture sector is the
management of low and high
rainfall. Water is distributed to
agricultural lands by a system
of drainage and irrigation
canals and therefore the proper
functioning of these systems is
one of the most important
adaptation measures
Drainage Sluice
Drainage Pump & Sluice
Drainage Canal
Maintenance of Key Drainage and Irrigation Facilities
Dredging Equipment
(Maintenance of Outfall Channels)

In 2008, GOG expended 2.5 M US in maintenance of D& I
Infrastructure.
CLIMATE CHANGE AND GUYANA
Guyana’s Coastal Plain is about 1.4 metres
below mean high tide level and approximately
2.1 metres below the flood and water control
dams inland
The Costal Plain is bordered by natural and
man-made sea defences measuring 430 km
long in the North and flood control dams and
dykes in the South that allows for the
settlement of 90% of the country's population
and consists of the most fertile lands in the
country
OBSERVED CHANGES:
Sea- Level Rise :Guyana’s Initial National
Communication in Response to its
Commitments to the UNFCCC (2002)
projected sea-level to rise by about 40 cm to 60
cm by the end of the twenty-first century due
to Global Warming
Analysis of tide gauge records from 1951-1979 shows the trend
in sea-level rise for Guyana to be in excess of 10mm/year, which
implies a net change in sea-level of 0.9 feet over the 28 yr period
Sea-level rise will have significant negative socio-economic and
bio-physical implications on Guyana if systems are not put in
place to adopt to it
Climate change has already resulted in significant damage to the
current Sea-Defence system by eroding mangrove ecosystems
through increased wave activities, loss of infrastructure and salt
water intrusion that result in abandonment of land.
Temperature Rise: The records in Guyana suggest an
increase by 1.0°C of the mean annual temperature within the
last century (TFIR, 2005).
Changes in Rainfall Patterns: Prior to 1960, annual rainfall
amounts were generally above or about normal. From 1960
and onwards, there has been a tendency for below normal
rainfall and an increase frequency of short duration above
normal rainfall (TFIR, 2005).
GUYANA’S FLOODS IN 2005
From the 14th to 22nd of January 2005, the coastal regions of
Guyana received some 1108.2 mm or 43.6 inches of rain. The
heaviest rainfall record since 1888 and resulted in the country's
worst flooding.
Most of the rainfall occurred over the Coastal Plain in Guyana and
the Water Conservancies, EDWC and BWC.
These areas are considered the most important natural regions in
the country since 90 % of the population, as well as economic and
administrative activities are concentrated.
The torrential rains and subsequent flooding resulted in severe
physical damage and economic loss to the country. Extensive
flooding lasted from 1 to over 3 weeks in some areas in the
administrative Regions 3, 4 and 5 including the capital city,
Georgetown, where over 62% (463,300) of the nation’s population
reside
The magnitude of the damage caused by the floods is estimated
to be equivalent to G$92.2 billion or 59% of current GDP for the
year 2004. The agriculture sector was the hardest hit with severe
damage to the two principle crops, Rice and Sugar.
This event resulted in loss of 34 lives, disease outbreak, loss of
crops, livestock, population displacement and infrastructural
damage.
Flood condition in Mon Repos
Flood condition in Mahaicony Creek
Flood condition in Good Hope
Georgetown, Region No. 4
Mahaica, Region No. 4
Mahaicony, Region No. 5
Flood Hit Regions, 2005
Failure of the EDWC dams in January 2005 did not occur.
However significant overtopping did occur, thus compounding
the flood situation . Comparison of flood levels with a crest
level survey undertaken by the GLSC in 2005 suggests that 10
% of the length of the dam was overtopped [TFIR, 2005].
Initiatives towards Adaptation/Mitigation of Climate Change
in D&I Sector
Conservancy Adaptation Project
Institutional Measures; Maintenance of D&I System
Introduction of more Mechanical Means of Drainage
(GDRP)
New Dredging Technology
Rip Rap Designs (Flexible Wall), 9th European
Development Fund
Improved Design of D&I Infrastructures (Relevant Data)
Construction Criteria
East Demerara Water Conservancy
Background of the EDWC: The EDWC was constructed over
150 years ago by damming the Lama and Maduni creeks, a
number of water courses and tributaries.
The EDWC functions as a flood control structure during the
rainy periods and simultaneously store water for irrigation in
the dry season.
Raw water is also tapped from the EDWC, treated and supply
the city with potable water.
Data on EDWC:
Surface Area:
130 sq.miles
Catchment Area:
200 sq.miles
Length of Perimeter Dam: 45 Miles
Full Storage Level:
57.5 GD
Dead Storage Level:
53.5 GD
Relief Structures:
Lama Relief Sluices:
Discharge into Mahaica Creek
Maduni Relief Sluice:
Discharge into Maduni Creek
Land of Canan Sluices: Discharge into Demerara River
Cunia Relief Sluice:
Discharge into Demerara River
Friendship (Kofi) Sluice: Discharge into Demerara River
Areas Provided with Water
Sugar Cane:
Rice:
Vegetables:
Orchards/Coconuts:
13,000 hectares
2,500 hectares
500 hectares
2,000 hectares
Water Management and EDWC
90.0
80.0
70.0
60.0
50.0
40.0
30.0
20.0
10.0
0.0
58.00
56.00
54.00
52.00
50.00
48.00
46.00
1D
3- ec
D
5- ec
D
7- ec
D
9- ec
D
11 ec
-D
13 ec
-D
15 ec
-D
17 ec
19 D ec
-D
21 ec
-D
23 ec
25 D ec
-D
27 ec
-D
29 ec
31 D ec
-D
e
2- c
Ja
4- n
J
6 - an
Ja
8- n
J
1 0 an
12 Jan
-J
1 4 an
-J
1 6 an
18 Jan
-J
2 0 an
-J
2 2 an
24 Jan
-J
2 6 an
-J
2 8 an
30 Jan
-J
an
ELEVATION (GD)
60.00
Dec 2006/Jan 2007 Rainfall
Dec 2008/Jan 2009 Rainfall
Dec 2007/Jan 2008 WL
38.1 mm Rainfall
Dec 2005/Jan 2006Rainfall
Dec 2006/Jan 2007 WL
Dec 2008/Jan 2009 WL
Dec 2007/Jan 2008 Rainfall
Dec 2005/Jan 2006 WL
Avg. Dam Level
RAINFALL (mm)
GRAPH SHOWING DECEMBER TO JANUARY RAINFALL & WATER LEVELS IN THE EDWC FOR THE
YEARS 2005 - 2009
Conservancy Adaptation Project: EDWC
Project Objective: To reduce vulnerability of catastrophic
flooding in low-lying costal areas by developing technical
master plan for future investment in improving and
upgrading the drainage system.
Deliverables (Medium & Long Term):
a) Development of a Hydraulic engineering foundation for flood
control and water management.
b) Recommendation on 10 key drainage projects/regime aimed
at improving or upgrading the drainage system.
c) Improved discharge capacity of the EDWC by 30%-35%.
d) Strengthening of the GOG institutional capacity in flood
control and water management.
Project Components:
Component 1- Pre-investment studies for engineering
design of works ( US 2.1 m, GEF).
Objective; Develop the hydrologic baseline, detailed elevation
model, mapping of the local water shed characteristics and drainage
regimes for future engineering interventions will be achieved
through:
- Detailed topographic and land use mapping
- Hydrologic/hydraulic modeling of EDWC and costal lowlands
- Assessment of EDWC structural integrity
- Operational Capacity building within the GOG agencies
- Pre-feasibility studies for costal lowlands interventions
Component 2- Investments in specific adaptation
measures ( US 2.9 m, US1.7 GEF, US1.2 m from GoG).
Objective; Improve the overall discharging capacity of
the EDWC during rainfall and to counteract the effects of
sea level rise:
- 2.1 Widening of key drainage relief canals
- 2.2 Improvement of Water flow system within EDWC
- 2.3 Upgrading of Water control Structures
- 2.4 Selected equipment purchase and installation
Land of Canaan Sluice
Lma Sluice
Maduni Sluice
Strengthen of embankment
Component 3- Institutional Strengthening and Project
Management ( US 0.1 m, GEF,).
Objective; Strengthen the institutional framework of the
national emergency management sector, Civil Defense
Commission:
- 3.1 Contingency plan for flood events
- 3.2 Consolidation of flood control actors
- 3.3 Monitoring and evaluation of project progress
- 3.4 Project management
Expected Impact: Components 1& 3
The development of engineering data and models, will result in the
preparation of future works & bidding packages for future execution
through the GOG and Donor Agencies.
Improving the government’s ability to protect over 75% of population
in Guyana and its capital from flooding associated with drainage
system and failure of the EDWC dam.
Development of an engineering tool to be used as a foundation for
determining the environmental impacts of follow-on interventions.
Expected Impact: Component 2
Investment in specific adaptation measures; rehabilitation of relief
drainage structures.
Increasing the discharging capacity (30-35%) by rehabilitating the
Cunha relief channel and associated structures, less need to
operate the eastern reliefs.
Lessons learned and reflected in Project Design
Loss of Information: Analytical output of CAP will be
distributed to GOG agencies who will be trained in data
management and analysis.
Implementation delays at procurement stage: Due to rebiding, high bid cost, too big contract package, etc.
Tenders under this project is divided in 3 package.
Lack of expert firms to undertake specific service:
Tender criteria developed to attract both local and
international expert firms.
Conclusion:
The effects of climate change will only get worst in the
years ahead especially in small developing countries
such as Guyana. Therefore, it remains a priority to
intensify our efforts in adaptation/mitigation measures by
working with our Caribbean and international partners. In
this regard, the development and implementation of CAP
will seek to upgrade the functioning of the EDWC and
recommend mitigation projects for implementation in
highly vulnerable low costal region in Guyana to
safeguard some 300,000 acres of agricultural land.
Hope
(07/01/09)
Thank you.