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A detailed scientific analysis of the impact
g on water resource
of land use change
provision to Bogotá D.C. and implications
for the development of PES schemes
Chingaza
Park
Bogotá
City
Chingaza
Park
Guavio
catchment
Golillas
Guavio
Sumapaz
Park
Leonardo Sáenz and Mark Mulligan
Environmental Monitoring, Modelling and
Management Group
Description
1.
KCL objectives
2.
USE of FIESTA model and main datasets
3.
Implementation of other FIESTA model
components
4
4.
M i h
Main
hydrological
d l i l findings
fi di
5.
Main policy implications
6.
Main Conclusions
KCL objectives
1.
Produce a baseline scenario of water
resources p
provision to dams from forests
and paramos surrounding Bogotá D.C.
2
2.
Estimate
E
i
potential
i l hydrological
h d l i l benefits
b
fi off
forest and paramo conservation through
PES schemes
h
for
f different
diff
t scenarios
i off
land cover change to the year 2050.
2.
Estimate potential economic effects of
PES conservation on water provision and
hydroelectric power generation.
FIESTA Delivery Model
FIESTA is the most sophisticated model of mountain hydrology
to help understand the magnitude of fog contributions to the
water balance at national and regional scales (Mulligan and
Burke 2005).
FIESTA models:
* fog interception
p
* evaporation
* water balance
* Accumulated water
b l
balance
(runoff).
(
ff)
With appropriate soils
data it also models:
* soil hydrology
y
gy
* estimates sedimentation
yields.
FIESTA is applicable elsewhere with appropriate data processing an
uses globally available datasets and free software.
FIESTA implementation - datasets
- Humidity (%)
- Temperature (°C)
- Wind speed (m s-1)
s 1)
- Wind direction.
- Precipitation (mm)
- Air
Ai pressure (mb)
( b) and
d
- Cloud frequency (%).
- Potential solar radiation
(W m-2).
- Elevation (m).
- Land cover: % of tree
cover (MODIS VCF)
- Roads and river streams.
N
Baseline1977
Land Cover Classes
Paramo
Forest
Crops
Bare soil
Baseline2000
Land Cover Classes
Paramo
Forest
Crops
Bare soil
Creation of Land Cover Change scenarios.
Forest and paramo resources to the years
1977 and 2000 surrounding Bogotá D.C.
Derived from Landsat and MODIS datasets
FIESTA scenarios – year 2050
N
PES scenario:
Forest and
paramo loss
avoided within the
Chingaza park
NO PES scenario:
Forest and
paramo loss
Allowed within the
Chingaza park at
Current rates
79,000
39,500
0
79,000 Kilometers11,000
5,500
0
11,000 Kilometers
PES and NOPES scenarios, detail of natural cover loss in the
Chingaza National Park.
FIESTA Components: Paramo
a
M d lli off paramo water
Modelling
t storage,
t
retention
t ti and
d
contribution to runoff
FIESTA Components: dam filling
Guavio
dam
Water storage and discharge
discharge, hydraulic head
head, and
hydroelectric generation potential.
FIESTA and Dams database
Main dams surrounding Bogotá D.C.
Dams database - KCL effort to enhance the knowledge of hydrological impacts
from land cover and climate change upon highly engineered human infrastructure
Main hydrological findings
Cloud forest hydrology and implications to dams
Tota
Tota
N
Copa
Copa
Neusa
Neusa
Sisga
Sisga
Tomine
Tomine
Chivor
Guavio
Guavio
Golillas
Golillas
Chingaza lagoon
Prado
Chivor
Regadera
Regadera
Chingaza lagoon
Prado
Overall: Fog inputs are of major importance in dry areas to the
north of the Bogotá region and in the western fringes towards the
Magdalena basin, where Tota lake and Copa, Sisga, Tomine, Chivor
and Prado dams receive important seasonal fog inputs.
Main hydrological findings
fi di
Deforestation impacts on fog inputs and
implications to dams
a. Overall: Fog inputs are already minor in most of the flat areas of
the high Bogotá sabana since most of the cloud forest resources
have already been converted to other land uses
uses, but not so in the
steep slopes surrounding Chingaza and Sumapaz parks.
b. Deforestation
b
D f
t ti
has
h already
l
d potentially
t ti ll increased
i
d flows
fl
for
f mostt
of the dams in the region.
c. However, further deforestation threatens the seasonal
regulation of base flows to dams especially in the driest areas, for
Copa,
p , Tomine,, Sisga
g and Chivor dams,, where fog
g inputs
p
are an
important proportion of seasonal water balances.
Main hydrological findings
fi di
Paramo loss and implications to dams
a. Overall: Climatic and topographical conditions and high water
balances with regard to the high Bogotá sabana make paramo
areas essential to sustained water supplies to Bogotá City.
b. The importance of paramo conservation is with respect to
maintaining water quality and regulation. Much research is
needed to better understand the g
generation of the runoff
phenomenon in undisturbed and intervened paramo
catchments.
M i policy
Main
li implications
i li ti
Implications to PES
a. In dry areas to the north and south west Bogotá D.C surrounding Tota
lake and Sisga,
g , Copa,
p , Chivor and Prado dams,, deforestation and thus
the reduction in fog interception affects river flows seasonally.
b In paramo catchments surrounding areas of Chingaza lake,
b.
lake Golillas
Guavio and regadera dams, where flows are not enhanced by
deforestation and could even reduce with increased evapotranspiration when paramo is converted to pasture or crops,
conservation measurements are essential to maintain regular flow
regimes and water quality downstream.
M i policy
Main
li implications
i li ti
Implications to PES
a. In highly engineered systems any change in flows exciding design
specifications is bad. Therefore, PES schemes could potentially
maintain the safety
y of operation of hydraulic
y
infrastructure in Golillas
and Guavio dams.
b E
b.
Economic
i impact
i
t off infrastructure
i f
t
t
f il
failure
d to
due
t increased
i
d peak
k flows
fl
has yet to be estimated in the surrounding areas of Bogotá D.C.
M i policy
Main
li implications
i li ti
Implications to PES - Economic Estimates
a Implementation of PES schemes preventing the loss of paramo in the
a.
Chingaza park could potentially maintain up to 0.9% of hydropower
generation of the Guavio dam to the year 2050 (up to about 3.2 USD
million year-11).
)
b. PES implementation in the Chingaza park could potentially conserve
up to 3.8%
3 8% of water inputs to Golillas dam from paramo conservation
to the year 2050 (up to about 6.2 USD million year-1).
c. Further enhancements of the paramo protected area in Chingaza
would help maintain seasonal water resources that would otherwise
be lost if paramo loss takes place at the same rates of today.
Conclusions
a. Results from paramo conservation are encouraging since
conservation efforts through
g PES schemes could p
potentially
y represent
p
positive economic impacts
b. Study outcomes must now be validated and compared with
information from respective relevant drinking water, hydroelectric and
environmental organizations and understood within the economic
context of the provision of these services in the region to support and
potential
t ti l PES schemes
h
i l
implementation
t ti surrounding
di
B
Bogotá
tá D.C.
DC
c. Conservation of cloud forest and p
paramo resources should be tackled
not only considering potential benefits of water quantity but of water
quality and flood mitigation specially in the eastern Andes, which are
essential to the efficient, economic and safe operation
p
of dams in the
region.