Belo Horizonte Threats and Uncertainties

Belo Horizonte Threats and Uncertainties
Belo Horizonte, October 2006
Urban Waters in Belo Horizonte
Belo Horizonte (BH)is the capital of the State of Minas Gerais, which in economic terms
(gross product) is the third among the 26 Brazilian states. The city lies at 20° South latitude
and 44° West longitude (Figure 1) and has an altitude of 750 to 1,300 meters. It is located in a
mountainous region of tropical soils that originated from the decomposition of metamorphic
rock. Tropical highlands weather predominates in this area, with average yearly rainfall of
1,500 mm and average yearly temperature of 26oC. The rainy season lasts from October to
March, when 90% of the total yearly rainfall occurs. The highest monthly average rainfall
(315mm) takes place in December. Typical rainfall intensities are also relatively high (e.g.:
200 mm/h in the case of a 10-year return period event with 5 minutes duration; 70 mm/h for
the 1h and 50-year return period event). Mean relative humidity reaches 50% during winter
and 75% in summer.
Figure 1 – Location map of Belo Horizonte (Nascimento et al, 1999)
BH has 2,227,400 inhabitants with a population density of 6,900 inhabitants/km2. It is a
planned city, built in 1898 to become the capital of the state. The total area of the municipality
is 330 km2. BH is inserted into a metropolitan area; the RMBH (Belo Horizonte Metropolitan
Area), gathering 33 distinct municipalities, with an area of 9,179 km2 and 3,900,000
inhabitants.
The Belo Horizonte territory locates at two main catchments (Arrudas creek and Onca creek
catchments), each representing at about 50% of the total municipal area (Figure 2). Part of
those catchments locates at neighbourhood municipalities: Contagem, upstream of Belo
Horizonte, and Sabará and Santa Luzia, downstream of Belo Horizonte. There are no rivers in
the municipal territory, although Arrudas and Onça are direct tributaries of the Velhas River,
with a total drainage area of about 40,000 km2, which itself is the tributary of the Sao
Francisco River, the longest one entirely within Brazilian territory (approximately 600,000
km2 of drainage area).
2
Figure 2 – Arrudas and Onça creek catchments and the Belo Horizonte municipality borders
The water supply system (dinking water) connects 99.7% of BH residents with an average
supply rate of 286 litters per inhabitant/day (Table 1). The water supply system presents high
quality standards in operational as well as in water quality terms.
3
Table 1 – Water supply at Belo Horizonte: basic figures
Number of inhabitants
2,277,402
Population connected to the water supply system (inhabitants)
2,271,059
Percentage of inhabitants connected to the water supply system (%)
99.7
Number of connections
469,058
Number of economies connected to the water supply system
802,647
Length of the water supply network (km)
5,113
Percentage of connections equipped with flow meters (%)
98.8
Sources: COPASA and SNIS – Sistema Nacional de Informações sobre Saneamento (SNIS, 2001)
Surface sources predominate in the BH water supply system (Table 2). There are four main
sources, namely:
• Velhas (Velhas River Basin) with a capacity of 6.75 m3/s;
• Manso (reservoir, maximum storage: 121 hm3) with a capacity of 4.2 m3/s;
• Serra Azul (reservoir, maximum storage: 93 hm3) with a capacity of 2.6 m3/s;
• Vargem das Flores (reservoir, maximum storage: 44 hm3) with a capacity of 1.2 m3/s.
Manso and Serra Azul are located at about 60 km from BH. Velhas and Vargem das Flores
are relatively closer. Vargem das Flores, Serra Azul and Rio Manso withdraw water from
tributaries to the Paraopeba River. The Paraopeba river basin has a total surface of 14,000 km2
and the river is also a tributary of the Sao Francisco River. The other systems are located at
the Velhas river basin.
Table 2 – Production of drinking water for Belo Horizonte and its metropolitan region
Water supply system
Full capacity
Average
production (2005)
(m3/s)
(m3/s)
Production for the BH
municipality
(m3/s)
(%)*
Ibirité system
0.45
0.322
0.177
55
Morro Redondo system
0.75
0.543
0.750
100
Água Bruta Barreiro system
0.20
0.030
0.200
100
Água Bruta Catarina system
0.17
0.110
0.170
100
Rio das Velhas system
6.75
4.922
4.233
86
Vargem das Flores system
1.20
1.009
0.252
25
Serra Azul system
2.60
1.500
0.435
29
Rio Manso system
4.20
3.427
1.371
40
16.32
11.863
7.588
64
Total
Source of data: COPASA MG
* Percentage of the RMBH water supply full capacity ascribed to the Belo Horizonte municipality.
All the systems are interconnected and supply not only BH but also most of the municipalities
gathered into the Metropolitan zone.
4
In BH, about 92% of population is connected to the wastewater sewerage system but there is a
lack of interceptor pipelines and wastewater treatment facilities (Tables 3, 4 and 5). There are
two relatively recent wastewater treatment plants in operation, the Arrudas WWTP (Figure 3)
and the Onça WWTP, with a total capacity to treat 4.0 m3/s. In the future, those WWTP will
have their total treatment capacity increased to 8.1 m3/s and will then be able to treat almost
100% of the total wastewater flow generated at the Arrudas and Onça catchments, including
wastewater drained from Contagem municipal area located upstream in both catchments.
Table 3 – Belo Horizonte wastewater system: basic figures
Population connected to the sewerage system (inhabitants)
2,223,943
Percentage of inhabitants connected to the water supply system (%)
91.7
Number of connections
466,458
Length of the water sewerage (km)
3,806
Percentage of treated wastewater volume in respected to total wastewater volume (%)
38.0
Source: COPASA (www.copasa.com.br, 2006)
Table 4 – WWTP at Belo Horizonte
Wastewater Treatment Plant
Treatment Process
Operational capacity
(m3/s)
Arrudas (secondary)
Conventional activated sludge
2.25 (1st stage)
4.50 (2nd stage)
Onça (secondary)
Upflow anaerobic sludge blanket
(UASB) reactors
1.80 (1st stage)
3.60 (2st stage)
Pilar/Olhos d'Água (primary)
UASB reactor
0.017 m3/s
Pampulha
Physico-chemical and flotation
0.75 m3/s
Table 5 – Interceptor pipelines in Belo Horizonte
Lengh of interceptors
Required
Existing
To be built
Catchments
Total
Arrudas
(km)
Onça
(km)
Velhas
(km)
(km)
278
96
182
301
161
140
6
0
6
585
257
328
Source: GGSAN (2004) and COPASA (www.copasa.com.br).
5
Figure 3 – View of the Arrudas WWTP (Papiri and Raverai, 2005)
In Belo Horizonte as well as in all the BH metropolitan area, a separated sewerage system is
adopted, although illicit inter-connections between wastewater and stormwater networks
prevail, resulting in heavily polluted receiving bodies in the urban area and downstream the
city (Velhas River). Another source of water pollution by wastewater is the lack of interceptor
pipelines (Figure 4) as part of the main sewerage system (Table 5). Therefore, improvements
on urban creeks, detention ponds, wetlands, and in the Velhas River water quality will require
important investments in wastewater interception. Alternatively, a new approach, which may
combine the existing end-of-pipe WWTP with decentralised treatment facilities, may be
adopted.
Figure 4 – Pollution of receiving bodies by wastewater due to lack of interceptors
6
Another point under evaluation by the BH municipality is the possibility of keeping combined
systems in certain areas where in fact this approach has been informally adopted (e.g.: in
many of the shantytowns). Embracing such an approach will require improvements on those
existing systems in order to eliminate continuous outflows in receiving waters (Figure 5) and
to employ modern solutions for the reduction of CSO (e.g.: retention structures).
Figure 5 – Creeks heavily polluted by wastewater and solid waste
7
In Brazil, as stated by the federal legislation, water supply and sanitation are public services
under municipal responsibility. In BH, COPASA, a state company1, provides those services,
by concession.
Since its creation in the 60s till the end of the 90s, COPASA, like all the other Brazilian state
water utilities, had been in charge of planning, operation, control and regulation of the BH
water supply and the wastewater systems. Recently, BH municipality decided to recover its
role on water supply and sanitation planning and regulation, a new policy that led to
modifications on the municipal legislation for the sector (e.g.: Municipal law 8260/2001
stating the municipal policy on water supply and sanitation) as well as on the concession rules
(e.g.: the Cooperation Agreement between COPASA and the BH municipality, from
November 2002, for the provision of drinking water and sanitation). As one of the outcomes
of those political changes, the municipality became shareowner of the COPASA state utility
(Municipal law 8754/2004).
Further than the concession contract amendments, other instruments and institutional
improvements were set up by the BH municipality in order to allow the development and
implementation of a comprehensive municipal policy for drinking water and sanitation:
• The Municipal “Saneamento” Committee (COMUSA), composed by municipal staff
and stakeholder representatives, having as main purpose the statement of a water
resources management policy for the municipality (“saneamento” means, in
Portuguese, drinking water + wastewater +stormwater + solid waste);
• The Municipal “Saneamento” Fund, stated with the purpose of contributing to finance
actions on water supply and sanitation at BH (Decree 11289/2003);
• The Water Supply and Sanitation Strategic Plan; and
• The Municipal Conferences on “Saneamento”, an instrument of intense public
participation on the decisions related to the water supply and sanitation policy.
Stormwater management has been entirely under the responsibility of the BH municipality
since the city foundation. Traditional storm water systems prevail in the city, although
experiences with detention ponds exist since the 50s. There are at about 4,300 km of roads all
of them equipped with gutters, inlets etc. The municipal database on drainage infrastructure
keeps details about 64,000 inlets (gullies), 11,500 manholes, 1,100 outflow structures
(outfalls), and almost 770 km of stormwater sewers. There are some 700 km of perennial
creeks in the municipal area. Part of those creeks have been lined, most of them as culvert
concrete channels. The length of lined channels reaches near to 200 km (Figures 6 and 7).
The creek lining policy, which prevailed up to the 90s, was mainly justified by the following
rationale:
• Lining is required for increasing the flow velocity and the channel conveyance,
reducing the flood risk;
• Lining makes easy the implantation of interceptor pipelines and the so called sanitary
roads;
• Lining makes easy the creek maintenance;
• Health risk due to directed contact with polluted waters may be reduced by creek
lining (see Box 1 for an assessment of health risk associated to creek lining
approaches);
• Inhabitants of riparian zones usually ask for creeks to be lined.
1
State utility here refers to the Minas Gerais state.
8
Using concrete box culverts as a “solution” to aesthetic, odour, garbage and water-borne disease
problems related to heavily polluted streams demonstrate an oversimplified approach of stormwater
management.
Legend:
lined creeks
natural creeks
Figura 6 – Belo Horizonte hydrography
The apparent simplicity of stormwater management, as perceived almost during all the last
century, led to the use of very simple design methods for storm water systems. Synthetic
models were used which do not require observed data to calibrate parameters (e.g.: rational
method and synthetic unit hydrograph). Since observed data were considered as not necessary
for storm water management, during all the last century the BH municipality did not invest in
monitoring stream discharges or water quality parameters. One of the consequences of those
approaches is high uncertainty in hydrologic design. A similar oversimplification also
prevailed in hydraulic design. Complex flow conditions, including the effects of stream
confluence, flow transitions or unsteady flow, were infrequently regarded and model
simulations of these conditions were rarely done. Only uniform flow conditions use to be
9
regularly considered in the design of channel structures, which usually resulted in
underestimations of flood risk and flood effects.
Figura 7 – First lining works at the Arrudas creek during the 1920s.
10
BOX 1.: Association between types of intervention on riparian areas and health in developing
countries. The case of Onça Creek Basin, Belo Horizonte, Brazil.
Batista, Nascimento and Heller (unpublished paper)
The occurrence of floods due to heavy rains, the formation of rain water pools in places of poor
drainage, the waste carried by the drainage system, and the pollution of waters caused by sewers
discharge are potential factors for the dissemination of diseases in areas where the drainage system is
either inexistent or ineffective due to construction, design and operation problems.
Possible engineering works aiming to minimize such a situation include the treatment of riparian areas
(open and/or closed channeling) and the construction of intercepting lines bordering watercourses or
channels, preventing sewage from being poured in watercourses and, consequently, from
contaminating the waters. In fact, sewage should be conducted to treatment stations. However, such
practice is still not frequent in Brazil. Sewage is often poured in watercourses downstream the urban
areas.
In view of that, the present assessment was developed with the purpose of evaluating the association
between different types of intervention on riparian areas and health indicators, as well as that of
estimating the number of avoidable cases of diseases should treatment of the riparian areas be
expanded. Areas occupied by low-income families with no previous planning and no previous
approval from public agencies tend to have their watercourses unchanged, although even their banks
are occupied.
In general, when public agencies intervene in those areas, watercourses are channeled into closed
concrete structures, with the top of the gallery being used as road pavement. However, intercepting
lines, which are responsible for carrying sewage generated in their subbasins, are not always built. In
this case, domestic sewage keeps on being discharged into watercourses in the urbanized section. In
view of different “models” of urbanism, there has been possible to classify the types of intervention on
present riparian areas into:
1) No channeling, with no sewer collector;
2) No channeling, with sewer collector;
3) Closed channeling, with no sewer collector;
4) Closed channeling with sewer collector;
5) Open channeling with sewer collector.
The region of the Onça Creek basin was selected as the Area of Assessment, comprising a reach of
106,816.77 meters of creeks, as shown in Table B1.1. The Onça Creek catchment has a total drainage
area of 93.66 km2, thus comprising 58 districts served by 51 public health centers. In 82.90% of the
area the population density ranges from 0 to 86 inhabitants/ha.
For each creek, the Area of Exposure, inserted in the Area of Assessment, was materialized by two
lines parallel to its main channel, each one located 150 m distant for it. The length of the Area of
Exposure was equal to the length of the creek reach, thus presenting a homogeneous type of
intervention in its bed and riparian areas. The rationale for classifying the areas of influence is
discussed in a subsequent item (“Definition of exposure and no exposure conditions”).
The epidemiological method adopted was the case-control, and the population assessed were children
under five years old, as they are more susceptible to diseases related to lack of sanitation and hygiene.
Children who presented diseases such as diarrhea, intestinal parasitosis and dermatological diseases
have been considered as cases. The selection of these three disease groups was based on the
transmission mode, as related to the water factor, being recognized by the specific literature as a
suitable indicator to assess the impact of sanitation measures (Benenson 1997; Bennet & Plum 1990;
Heller 1998; Neves 1991; Sampaio & Castro 1985; Veronesi 1996).
11
Table B1.1 – Onça Creek catchment - situation of the riparian areas according to the type of
intervention
________________________________________________________________________
Types of intervention
Length (meters)
________________________________________________________________________
Unchanneled with no sewer collector
56,556.77
Unchanneled with sewer collector
7,036.54
Subtotal
Channeled (closed) with no sewer collector
Channeled (open and closed) with sewer collector
63,593.31
24,887.11
18,336.35
Subtotal
43,223.46
Total
106,816.77
_________________________________________________________________________
Combinations among health indicators were adopted, thus generating seven types of Cases:
1- Diarrhea;
5- Diarrhea and dermatological diseases;
2- Intestinal parasitosis;
6- Intestinal parasitosis and dermatological diseases;
3- Dermatological diseases;
7- Diarrhea, intestinal parasitosis and dermatological
diseases;
4- Diarrhea and intestinal parasitosis
Children presenting diseases defined by 86 selected groups of diseases, excluding those of the health
indicators adopted for the Cases, were considered Controls.
The definition of the 86 groups of diseases for the control group, selected out of a total of 95 groups,
were strictly evaluated with the purpose of excluding those records which were not suitable for the
assessment when taking into account potential ascertainment or selection bias. This type of
misinterpretation of results may happen when data are not subjected to quality control and/or suitable
supervision.
The geographic information system (GIS) for Belo Horizonte, used in the present research project, has
been previously developed by the municipal data processing company namely Empresa de Informática
e Informação do Município de Belo Horizonte (PRODABEL) on the base of a aerial photographic
surveys and cartographic data available in 1989. The MapInfo Professional software, version 4.1, was
used to geoprocess the records of cases and controls geocoded according to patient’s address. MapInfo
was also employed in bordering the areas of influence of the riparian areas, ensuring the correct
assessment of records) (Fig. B1.1).
In the Area of Assessment, 909 cases and 6,270 controls have been identified, out of which 413 cases
and 2,020 controls were located in the Area of Exposure. Children living within the 300 m area of
influence of the riparian reach, belonging to the Area of
Exposure, have been considered exposed, when the riparian areas were under one of the following
intervention conditions: unchanneled with no intercepting line; unchanneled with intercepting line;
channeled (closed) with no intercepting line. A channeled (open) riparian area with no intercepting
line was not found in the Area of Assessment.
Two definitions were adopted for no exposure: (1) children living within the Area of Assessment,
except those living in the Area of Exposure, and (2) children living on channeled (open and closed)
riparian areas with intercepting line.
12
The survey of exposure and no exposure condition was performed by local visits as well as by means
of information provided by Superintendência de Desenvolvimento da Capital (SUDECAP) and
Companhia de Saneamento de Minas Gerais (COPASA-MG). SUDECAP is the municipal company
responsible for storm water management as well as the construction and maintenance of other urban
infrastructures as roads and municipal buildings. COPASA is the state company in charge of water
supply and sewage collection and treatment in the municipality.
Figure B1.1 – Demarcation of the area of influence for counting of records of cases and controls (150
m on each bank of the creek)
Two risk measures were employed in the data analysis:
- The odds ratio – OR and respective confidence interval– CI of 95% (Rothman & Greenland
1998), as calculated by means of the EPIINFO 6.0 software;
- The attributable populational risk – APR, calculated by the equation below (Gordis 2000), where p
is the ratio between controls on unchanneled riparian areas with no intercepting line and total
controls, in the respective area (Area of Assessment and Area of Exposure):
APR =
p(OR − 1)
p(OR − 1) + 1
The analysis of the association between types of intervention on riparian areas and health indicators
has been divided into three large groups relevant for the assessment, as follows:
− First group: Comparison between Exposure and No Exposure conditions
− Second group: Comparison among the several types of intervention on riparian areas, under
Exposure condition
− Third group: Comparison by type of intervention on riparian areas, under Exposure condition
13
From the OR values found in the analysis of the three groups of associations, the following evidences
could be drawn:
− In nine associations of the first and second groups, the worst situation of risk to health was that of
unchanneled riparian area with no intercepting line, followed by riparian area with no
intercepting line.
− The associations of the third group presented neither statistically-significant results nor a
significant confidence interval. A possible hypothesis may be the inadequate sample size.
− The highest OR values, resulting from the seven combinations of case definitions, occurred in the
situations of exposure to unchanneled riparian area with no intercepting line and to channeled
riparian area with no intercepting line.
REFERENCES
Benenson, A .S. 1997 Manual para el control de las enfermedades transmisibles. 16ª ed.: OPS,
Washington, D.C.
Bennet, J. C. & Plum, F. 1990 Tratado de Medicina Interna. Editora Guanabara, Rio de Janeiro.
Gordis, L. 2000 Epidemiology. 2nd Ed, Saunders, Philadelphia.
Heller, L. 1998 Saneamiento y salud. OPAS/OMS, Lima.
Neves, D. P. 1991 Parasitologia Humana. 8th Ed. Atheneu, São Paulo
Rothman, K.J, Greenland, S. 1998 Modern epidemiology. 2nd Ed. Lippincott, Philadelphia.
Sampaio, S. A. P., Castro R. M. & Rivitti E. A. 1985 Dermatologia Básica. 3rd Ed. Artes Médicas, São
Paulo
Veronesi, R. 1996 Tratado de Infectologia. Atheneu, São Paulo.
The intense urban growth during the 70s (Figures 8 and 12) combined to inequalities in the
distribution of income led to huge impacts on water quality in receiving bodies and an
increase of flood risk (Figure 9) mainly due to the impacts of new urban developments,
caused by the increase of imperviousness and also to the occupation of flood prone areas.
Most frequently, flood prone areas are occupied by poor people precisely because the land is
less valued and inappropriate for legitimate construction (Figure 10).
Water pollution by wastewater and diffuse pollution, including solid waste carried by runoff, as well
as a result of intense erosion processes have caused the degradation of water quality in streams and the
reduction of conveyance of sewers and channels due to sediment deposits (Figure 11). Detention
basins have also been heavily impacted (Nascimento et al., 1999). An example is the Pampulha
detention basin case study (PDB), part of one of the city most important urban complexes (see Box 2).
14
Figure 8 – Urban development of Belo Horizonte from the 50s up to 2000.
Figure 9 – Flood event in the Arrudas flood plain area.
15
Figure 10 – Occupation of flood prone areas by low-income urban areas.
Figure 11 – Sediment and solid waste trapped at lined channels.
16
A close correlation was then observed between the population growth and the number of
flood events in Belo Horizonte (Figure 12). Also Figure 13 illustrates a spatial distribution of
flood occurrences in the BH territory.
2200
100
Ocor. Inundações
90
2000
População (x1000)
1800
1600
70
1400
60
1200
50
1000
40
800
30
População (x 1000)
Ocorrência de Inundações
80
600
20
400
10
200
0
0
1930
1940
1950
1960
1970
1980
1990
Década
Figure 12 – Population growth (dotted line) and number of flood occurrences (bars) from
1930 to 1990 (Champs, Aroeira e Nascimento, 2005)
BOX 2: THE PAMPULHA RESERVOIR
The Pampulha Reservoir, formed by the streams Ressaca and Sarandi, with catchment area of 95 km2,
is an important component of a urban development project aimed at expanding the city northwards,
interfering in the most important landscape of the region.
Figure B2.1 Pampulha Reservoir
17
The reservoir was conceived and installed with multi-objective aims, namely, flood control, water
supply, leisure and sports activities, sailing and rowing, cycling, etc. Originally, in 1958, the
reservation volume was of 18 million cubic meters and the water surface was 261 hectares.
The intense and disorganized urbanisation of the upstream catchment, originally a rural area, resulting
in a population growth of 300,000 inhabitants over 30 years, combined with adverse climatic,
pedologic and topographic factors, led to intensive erosion processes. Also, lack of adequate sanitation
and solid waste management caused intense water quality degradation in nearly all the tributaries to
the reservoir. Those combined processes caused a dramatic degradation of water quality and a
progressive and severe silting of the reservoir. With estimated average sediment flow rate reaching
450,000 m3/year, and after several sediment removal operations, its present storage capacity is
estimated at 45% of its original one. Figure B2.2 illustrates the progress of sediment deposits and the
loss of water surface area at the reservoir.
Figure B2.2. Evolution of the water surface of Pampulha from 1964 until 2000 (Bandeira,
2004)
The reduction of its storage capacity resulted in a significant limitation of its flood control functions,
leading to an overload of its hydraulic structures (spillways) and to critical operational conditions of
the downstream drainage system, which a hydraulic capacity limited to the 10-year return period
event. This level of hydrologic risk is incompatible with the dense occupation of the downstream area,
equipped with important urban infrastructures, including one of the city airports.
The Pampulha reservoir is also impacted by illicit disposal of sewage and waste materials, facing
eutrophication and associated aesthetic problems. The intense growth of aquatic plants, mainly
Eichornia crassipes, favoured by the incidence of intense solar radiation all along the year, leads to the
silting and the subsequent decomposition of organic matters, provoking the exhaustion of the
dissolved oxygen. As a consequence, a prevalence of anaerobic conditions in the deep reservoir layers
is observed with a subsequent generation of bad odours. The water quality conditions of the reservoir
became so degraded that made unfeasible its use for water supply, since the decade of 1980.
Favourable conditions still prevail for the development of insects of other vectors of water borne
diseases.
Recently the Belo Horizonte municipality implemented a program, named PROPAM, aiming to the
pond structural, aesthetic and environmental rehabilitation. As part of this project, works on sediment
retention and dredging, and on rearranging the silted materials were carried out aiming to conform an
island where a park has been implanted. At the main tributary to the reservoir an on-line wastewater
treatment plant (ETAF) has been implanted, allowing the treatment of the stream flow during the dry
season (Figure B2.3). Due to the reduction of flow attenuation a new spillway had to be also implanted
in order to reduce dram break risk due to overtopping.
18
Figure B2.3. Partial views of ETAF and new spillway
With the implementation of the Storm Water Strategic Plan (SWSP) combined with the Water
Supply and Sanitation Strategic Plan (WSSSP) the formal stormwater and sanitation policies
have recently changed. As an example, an ongoing programme, the DRENURBS programme,
aims to keep natural the remaining natural creeks in the urban and suburban areas. This
program is supported and partially funded by the BID (Inter-American Development Bank –
IDB). The SWSP includes the building of some 40 new detention basins in the urban area,
with a main purpose of flood control. There are still relatively few concerns related to
stormwater diffuse pollution, although the problem obviously exists, mainly because pollution
of water bodies by wastewater is intense enough to mask effects of diffuse pollution on water
quality.
As part of the SWSP the BH municipality has already implemented actions as:
• The survey programme on land use and on stormwater existing infrastructure, assessing
the physical characteristics of all the existing system components;
• The stormwater maintenance programme focusing on the present BH storm water infrastructure, involving structural renovation of drains, culverts, lined channels, natural
channels, etc;
• The implementation of a GIS and a database system gathering data about the storm water
system. This GIS is compatible with the previous and more general municipal GIS which
contains a huge data base about BH (many layers on land use, road system, public
buildings, health care system, etc).
19
Figure 13 – Number of reported flood occurrences in the period 1922-2002 (colour scale:
yellow stands for less then 10 occurrences; red for more than 30 occurrences).
20
Presently, the on-going Stormwater Strategic Plan and the Water Supply and Sanitation
Strategic Plan focus on the following programmes:
a) the DRENURBS programme: creek restoration in the urban area, which involves not
only the restoration of polluted creeks but complete sanitation, risk management (risk
of flooding, risk to public health …), and a housing programme addressed to people
living in risky areas (improvement of housing conditions, removing people from risky
areas);
b) the stormwater monitoring programme: establishing and operating a rainfall, discharge
and water quality measurement network to allow the identification of BH stormwater
present problems and to contribute to the future evaluation of the efficiency of control
measures eventually implemented according to the stormwater plan issues. This
programme will also contribute to impact assessment of urbanisation on water
resources and to the statement of land use regulatory measures aiming the mitigation
of those kinds of impacts.
c) the rainfall-runoff and hydraulic modelling programme: data generated by the
monitoring program will feed models that will be employed in diagnosing the storm
water system functioning, in devising main causes of system functioning problems and
failures and in the simulation of different scenarios of control measures. The first
phase of the programme is starting in 2006. In this phase, modelling will be performed
previously to the monitoring program, using data from the existing rainfall
measurement network and from detailed surveys on land use and on the stormwater
sewerage system characteristics, already concluded. Modelling results from this phase
will be useful in devising actions to deal with critical and urgent problems and in
designing the monitoring network.
d) the research and technological development programme: the main programme goal is
the development of stormwater management technology to face stormwater main
problems. Although the final scope of the programme has not yet been concluded, the
following themes will certainly be part of it:
• physical modelling of specific hydraulic structures, like gutters, culvert entrances
and confluences with the purpose of efficiency evaluation under particular
conditions that prevail in BH (steep channels, high flow velocities, frequent
changes in water flow regimes, …) and design criteria statement;
• evaluation of the volume of solid waste transported by the storm water system
during storms and assessment of the waste typology (this is a common problem in
many Brazilian towns, due to failures in solid waste management);
• experimental investigation of the efficiency of source control devices (BMP:
infiltration trench, pervious pavement, detention facilities, …) in terms of runoff
and pollution abatement, maintenance requirements, building and operational
costs, design criteria statement, etc – this will be done by pilot experiments –
although there is a quite important literature on this subject, local particularities
may be relevant (rainfall intensity, sediments and solid waste, public acceptance,
maintenance requirements, costs …).
• Assessment of benefices of flood control measures by economic evaluation of
direct and indirect flood damages.
e) the institutional and managerial development programme: this programme aims the
statement of legal, economical, institutional and managerial measures in order to
improve storm water management in the BH municipality.
For the development of those programmes, the BID contributes with 60% of the required
funds and the BH municipality provides the remaining 40%.
21
In BH, about 360,300 inhabitants live in shantytowns, poorly urbanized areas, mainly located
at hills around the legal urban area or in flood prone areas. Those areas are subjected to
frequent landslides or flooding during intense rain events occurring typically in summer. The
BH municipality has developed a successful risk management programme concerning
landslides and floods, which has reduced injuries, deaths and damages. It consists essentially
of preventive measures; mainly removing people from risk areas to safer locations, and the
development of emergency plans based on a network of small local risk management centres
equipped with rescue teams (health professionals, engineers etc…) and appropriate
equipment. Nevertheless, further progress still needs to be done in terms of more preventive
measures, urban development planning, and of course long term measures focusing on the
social and economic inclusion of people living in shantytowns.
Belo Horizonte Threads and Uncertainties
Long term threads and uncertainties associated to the Belo Horizonte urban development are
first and briefly discussed in terms of population growth and climate change. This discussion
in then followed by a list of potential risks associated to water supply and sanitation
infrastructure and services organised in a table form.
Population growth
Population growth in Belo Horizonte is virtually reaching a saturation state (Figure 14).
Present average population growth rate is at 1.1 % per year (from 1990 to 2000) and nearly
95% of the municipal area is already urbanised (Figure 8). It is important to consider that the
BH land use law still allows a considerable densification of the present urban occupation in
almost all the municipal territory, with exception of the central, very densely occupied area,
and zones of restricted densification. Nevertheless, this scenario of high densification seems
do not represent such a significant risk when one takes into account the mentioned present
population growth rate.
Inhabitants (*1000)
2500
2000
1500
1000
500
0
1890
1910
1930
1950
1970
1990
2010
Time (years)
Figure 14 – Population growth in Belo Horizonte.
22
Studies developed under the context of the Stormwater Strategic Plan assessed possible
impacts of population growth on the percentage imperviousness taking into account trends on
densification at each of the 111 elemental catchments of the BH territory. Figure 15 illustrates
the distribution of the percentage imperviousness according to the elemental catchments (subcatchments) of the Arrudas and the Onça catchments. Figure 16 illustrates trends on
percentage imperviousness increase at the same 111 elemental catchments.
Percentage imperviousness [%]
Rel. frequency
1
0,75
0,5
0,25
0
0
20
40
60
80
100
Arrudas
IMP [%]
Onça
Figure 15 – Percentage imperviousness empirical distributions for the 111 elemental
catchments from the Belo Horizonte territory
Increase on the percentage
imperviousness [%]
Rel. frequency
1
0,75
0,5
0,25
0
0
5
10
IMP increase [%]
15
20
Arrudas
Onça
Figure 16 – Trends on percentage imperviousness based on empirical distributions for the
111 elemental catchments from the Belo Horizonte territory (SUDECAP, 2000)
On the base of those data its possible to conclude that imperviousness at Arrudas catchment is
considerable higher than in Onça catchment. For instance, at the Arrudas catchment 50% of
the elemental catchments have percentage imperviousness higher than 75%, at the Onça
catchment this happens only for 25% of its elemental catchments. However, imperviousnessincreasing trends are more significant for the Onça than for the Arrudas catchment, in spite of
the fact that those trends do not reach increasing rates higher than 20% as forecasted by the
Stormwater Strategic Plan.
23
On the other hand, pressures due to population growth on water resources as well a variety of
environmental impacts due to rapid urban expansion may be consistently expected in the
metropolitan region of Belo Horizonte (RMBH), where population growth rates higher than
5% per year are still observed in certain townships (Tables 6 and 7). Part of this phenomenon
is due to the attractiveness of industrial and commercial activities as well to the quality of
public services at townships located near to Belo Horizonte. The low cost of land in those
peri-urban areas, in many cases illegal urban developments with poor infrastructure of public
services, may also partially explain this expansion process.
Table 6 – Population growth in Belo Horizonte and its metropolitan region
Municipality or Region
Period – population growth rate in % per year
1960/70
1970/80
1980/91
1991-2000
Belo Horizonte municipality
6.1
3.7
1.1
1.1
Total RMBH
6.1
5.0
2.5
2.4
RMBH except Belo Horizonte
6.2
7.5
4.8
3.9
Source: IBGE – Censos Demográficos, FJP/Plambel (1974) and Rigotti & Rodrigues (1994), apud
www.observatoriodasmetropoles.ufrj.br (visited in October 2006)
1950/60
7.0
6.2
Table 7 – Urbanization rate and population growth in Belo Horizonte and chosen
municipalities located at its metropolitan region
Municipality
Urbanisation rate
Population growth rate
(%) of urban population in
(%) per year
respect to total population
period: 1991-2000
1991
2000
Total
Urban
Belo Horizonte
99.7
100.0
1.1
1.2
Betim
94.9
97.3
6.7
7.0
Contagem
93.4
99.1
2.0
2.7
Nova Lima
84.0
97.9
2.3
4.1
Ribeirão das Neves
83.4
99.4
6.2
8.3
Sabará
83.3
97.7
2.8
4.7
Vespasiano
64.5
98.4
3.8
8.7
Total RMBH
94.0
97.5
2.4
2.8
Source: IBGE – Censos Demográficos, apud www.observatoriodasmetropoles.ufrj.br (visited in October 2006)
Another on-going process of urban expansion is due to the increasing interest of rich people in
new urban areas located in neighbour municipalities, the so-called condominiums. The
attractiveness of those new developments is explained by their sparse occupation and their
private security systems, not to mention that they are better endowed with green parks and
leisure facilities than in the BH urban area. In spite of their low occupation density, those
areas produce impacts on the environment, exert pressures on local natural resources (water,
forests) and led to a progressive privatisation of scenic landscapes and forested areas that
would have different uses in the future, including public access for leisure and sport activities.
Climate and Climate change
Figures 17, 18 and 19 and 20 illustrate long-term mean monthly temperature, precipitation,
maximum 24-hour precipitation, and relative humidity, respectively, in Belo Horizonte,
supposing time series stationarity.
24
o
Mean monthly temperature [ C]
24.0
22.0
T [o C]
20.0
18.0
16.0
14.0
12.0
10.0
0
1
2
3
4
5
6
7
8
9
10
11
12
13
Month]
Figure 17 – Belo Horizonte mean monthly temperature
Mean monthly rainfall depth
350
300
P [mm]
250
200
150
100
50
0
Jan Feb Mar Apr
Mai Jun
Jul
Aug Sep Oct
Nov Dec
Month
Figure 18 – Belo Horizonte mean monthly precipitation
The main climate characteristics of the Belo Horizonte area are the relatively small thermal
amplitude, in terms of mean temperatures, and a high seasonality of precipitation with very
dry winters and rainy summers.
Regionalisation studies on rainfall intensity, duration and frequency recently carried out for
the BH metropolitan region (RMBH), based on precipitation data coming from more than 20
recoding rain gauges having time series longer than 30 years did not detect tendencies
associated to climate change on precipitation depth or precipitation intensity at different time
steps (Pinheiro and Naghettini, 1998). In contrast, tendencies on temperature can be
identified, particularly in terms of mean temperatures (Figure 21). Nevertheless, one has to
recognise the difficulties in isolating global change effects from anthropogenic impacts at a
local scale, as in the case of development of urban heat islands due to increases of
impermeable areas and changes in vegetation cover and in wind patterns. In BH, part of the
25
trends in temperatures as highlighted by the 5-year moving mean are coincident with a period
of intense urbanisation from the 70s on (Figure 21).
Pmax24 [mm]
Max rainfall deph in 24 hours
180
160
140
120
100
80
60
40
20
0
Jan Feb Mar Apr Mai
Jun
Jul
Aug Sep Oct
Nov Dec
Month
Figure 19 – Belo Horizonte maximum 24-hour precipitation
Mean monthly relative humidity [% ]
85
80
Rh [%]
75
70
65
60
55
50
0
1
2
3
4
5
6
7
8
9
10
11
12
13
Month
Figure 20 – Belo Horizonte average monthly relative humidity
Regarding global change, a particular concern is about the possible synergetic combination of
global with regional climate changes due to local anthropogenic impacts caused, for instance,
by deforestation or urbanisation. Studies assessing regional and local impacts of climate
change are not numerous in Brazil. Nevertheless, according to Nobre, Assad & Oyama
(2005), the existing studies suggest that an increase in 20 C to 30 C on average temperature
may lead to a reduction of trees up to 25% at the “cerrado” area (savannah) and up to 40% at
the Amazonian forest, before the end of the 21st century. Those kinds of vegetation changes
may result in warmer and dryer climate, which may lead to water shortage, among other
possible impacts on water resources.
26
0
Mean annual temperature and 5 year moving average ( C)
Temperature [oC]
23.0
22.0
21.0
20.0
19.0
1910
1930
1950
Year
1970
1990
2010
Figure 21 – Belo Horizonte mean annual temperature and 5-year moving average
The IPCC (2001) report on possible impacts of climate change on urban areas, cited by Bigio
(2003), suggests:
• Expected increases in the scale, intensity, and frequency of rainfall resulting in
periodic flooding of flood prone areas and in landslides on geologically unstable
slopes, areas typically occupied by low-income informal settlements;
• Sewage treatment systems and solid waste disposal areas can be affected by flooding,
with possible contamination of water supply sources.
• An evolution to dryer climates is likely to compromise the replenishment of the water
tables and to reduce minimum flows, possibly implying in water shortage.
• Intense episodes of thermal variability could severely strain urban systems by adding
an environmental health risk for more vulnerable segments of the population,
imposing extraordinary consumption of energy for heating and air conditioning, and
disrupting ordinary urban activities;
• Increase possibility of fires at urban and forested areas, severe hail, and windstorm;
• Worsening urban air pollution exacerbated by increased ground ozone formation;
• Enhanced effects of urban heat islands due to higher overall temperatures.
Although assessments of those kinds of risks are not so far available for Belo Horizonte and
region, they are likely to happen in the future provided that forecasts on global change are
confirmed.
27
Long-term uncertainties and potential risks to urban waters in Belo Horizonte and the RMBH
Drinking water
Risk and
uncertainties
Water quality
degradation
Event
Comments and explanations
Accidental contamination of water sources
by the outfall of toxic substances.
Toxic algae bloom in reservoirs due to
catchment environmental degradation.
Interruption of water treatment plants, for
different time spells.
Higher risks at less protected catchments
(e.g.: Vargem das Flores)
Operational failures
Low risk considering high operational
standards
Higher risks at less protected catchments
(e.g.: Vargem das Flores). Risk of pollution
by Fe and Mg in reservoirs where those
metals are of natural occurrence (e.g.:
Manso and Serra Azul)
High health impacts in the case of
pathogens hardly removed by conventional
treatment processes (e.g.:
Cryptosporidium,Giardia) and virus.
Thermal inversion in reservoirs leading to
the mobilisation and mixture of previously
settled toxic components
High level of emergent pathogen
occurrences in water supply sources due to
environmental disruption
Existing instruments and means to
handle the risk and to mitigate
impacts
COPASA became owner of all the direct
contributing areas to more recently
implanted reservoirs (Manso and Serra
Azul). Cooperation between COPASA and
Contagem municipality led to the reduction
of urbanisation at the catchment upstream
to Vargem das Flores reservoir and to
investments on wastewater management.
Systematic reservoir monitoring system.
Operation rules for water withdrawal.
Water shortage
Flow reduction during dry seasons due to
global change and local anthropogenic
impacts on the hydrological regime.
Water supply rationing and risk of search
by the population of alternative unsafe
water sources
Conflicts related to
the use of water
and other natural
resources
Difficulties in ensuring water sources
protection and risk of water shortage or
water quality degradation due to conflicting
interests at the river basin scale.
Agricultural activities, including irrigated
cultures, mining and other industrial
activities are common at all the catchments
where the water sources for the RMBH are
located. Urbanisation exists in some of
those catchments.
Accidents related
to natural disaster
Disruption of water supply systems due to
natural hazards like flooding, fires or
landslides.
Failures on system
units due to lack of
maintenance or
ageing of
infrastructure and
equipments.
Leakage of water.
Key units (e.g.: pumping units, major
pipelines, …) may fail due to lack of
maintenance or ageing. Leakage of water at
the drinking water distribution system is
still high.
Part of the water supply system was
implanted at the beginning of the last
century.
Water resources management law and
environmental protection law have
consistent instruments to reduce and to
mitigate anthropogenic impacts. River
basin committees exist for the Velhas and
the Paraopeba River Basins, which are in
charge of formulating the water resources
management policy for those basins.
Nevertheless, there are still difficulties in
enforcing the law and in using all the
available water management instruments.
Water resources management law and
environmental protection law have
consistent instruments to handle conflicts
of water as well as other natural resources
use (land, forest, …). Difficulties persist on
handling urbanisation, particularly the
spreading of informal settlements. Urban
development plans and urban land use
legislation do not take into account impacts
of urbanisation on water and other natural
resources in an effective way.
Emergency plans exist, but there is need of
further developments on prevention and
mitigation planning to cope with those
kinds of risks.
Maintenance standards are high and
consistent. Nevertheless, a comprehensive
assessment on investment needs for the
modernisation of ageing systems must be
performed.
29
Contamination or
system failure
induced by
terrorism or
criminal
organisations.
Increasing costs
Sabotage, vandalism, water contamination
by toxic substances on purpose
Although there are no registers of those
kinds of actions in Minas Gerais, it is
convenient to take into account this kind of
risk possibly linked to criminal
organisations.
Increasing costs imposed by different
causes
Possible causes:
• Water resources pollution leading
to higher treatment costs
• Water shortage at present sources
implying on higher capital and
operational costs for withdrawing
water at remote sources
• Investment for de modernisation of
ageing systems
• Energy costs
A vigilance scheme exists; nevertheless it
is not able to cover all the system
components.
30
Wastewater
Risk and
uncertainties
Persistent and
chronic pollution
of receiving water
Event
Implementing interceptors is postponed.
Persistence of illicit connexions between
stormwater and wastewater sewerage
systems.
Lack of investments to increase WWTP
treatment capacity
Operational failure or poor operation of
WWTP leading to poor treatment
performance
Comments and explanations
Main causes may be lack of investments
for implanting interceptors associated to
high costs, political and social difficulties
for removing informal settlements from
riparian areas, making difficult interceptors
building.
Main causes:
• Technical difficulties in locating
and reducing that kind of
connexions.
• Need of training and information in
order to avoid new inadequate
connexions between the two
systems.
• Informal settlements (shantytowns)
usually “adopt” combined
sewerage systems.
Although of low risk, changes in policy and
planning may postpone investments in
treatment plants.
Main causes:
• Poor operational qualification;
• WWTP disturbed by wet weather
transient flows due to illicit
connexions between stormwater
and wastewater sewerage systems
Existing instruments and means to
handle the risk and to mitigate
impacts
The Belo Horizonte Sanitation Plan states
the complete equipment of the sanitation
system in 20 years.
The Brazilian Continuous Education
Programme on Water Supply and
Sanitation headed by the UFMG in the
Southeast Region focus on operational
capacity building. COPASA and PBH
are partner of this programme.
COPASA possesses maintenance high
and consistent operational standards.
31
Accidents related
to natural disaster
WWTP not equipped to remove nutrients
(nitrogen and phosphorous) and emerging
polluters as endocrine-disrupting
chemicals.
Disruption of wastewater systems due to
natural hazards like flooding or landslides.
Failures on system
units due to lack of
maintenance or
ageing of
infrastructure and
equipments.
Key units (e.g.: pumping units, major
pipelines, …) may fail due to lack of
maintenance or ageing.
Increasing costs
Increasing costs imposed by different
causes
System failure
induced by
terrorism or
criminal
organisations.
Uncertainties
related to sludge
final disposal
Sabotage, vandalism leading to system
disruption
Emerging polluting chemicals are not
usually monitored in Brazil. Awareness of
the problem is not wide.
Emergency plans exist, but there is need of
further developments on prevention and
mitigating action planning to cope with
those kinds of risks.
Maintenance and operational standards are
high and consistent. Nevertheless, a
comprehensive assessment on investment
needs for the modernisation of ageing
systems must be performed. This question
concerns mainly ageing sewerage where
maintenance is less regular then in the case
of the water supply distribution system.
Possible causes:
• Investment for de modernisation of
ageing systems
• Energy costs
Vandalism is not uncommon regarding
public service equipments, although this
kind of problem is not frequent regarding
wastewater units.
A vigilance system exists; nevertheless it is
not able to cover all the system.
32
Stormwater
Risk and
uncertainties
Event
Comments and explanations
Existing instruments and means to
handle the risk and to mitigate
impacts
Flooding
No significant changes or increase on the
occurrence of floods and damage caused by
floods.
Emergency plans exist, but there is need of
further developments on prevention and
mitigating action planning to cope with
those kinds of risks. Difficulties persist on
handling urbanisation, particularly the
spreading of informal settlements. Urban
development plans and urban land use
legislation do not properly consider
impacts of urbanisation on water and other
natural resources in an effective way.
Pollution of
receiving waters
by wet weather
diffuse pollution
No significant changes or even increase on
the wet weather diffuse pollution.
Main causes:
• Increase on imperviousness due to
urbanisation
• Lack of investments to correct
present hydraulic functioning
problems in the existing
stormwater sewerage system
• New developments (legal and
illegal) in flood prone areas
• Lack of proper maintenance
• Technology update is not
sufficient, persistence in using
oversimplified design methods
• Climate change alters storm
frequency and intensity
Main causes:
• Increase on imperviousness due to
urbanisation
• Lack of proper maintenance
• Technology update is not
sufficient, persistence in using
oversimplified design methods
• Wet weather pollution not properly
considered
• Failures in other sanitation sectors,
as in solid waste management.
High pollution of receiving waters by
wastewater outflows masks effects of
diffuse pollution. Difficulties persist on
handling urbanisation, particularly the
spreading of informal settlements.
Difficulties in controlling illicit solid waste
disposal on hills or directly on water
bodies. Urban development plans and
urban land use legislation do not properly
consider impacts of urbanisation on water
and other natural resources in an effective
way.
33
Persistent and
chronic pollution
of receiving water
Implementing interceptors is postponed.
Persistence of illicit connexions between
stormwater and wastewater sewerage
systems.
Lack of investments to increase WWTP
treatment capacity
Operational failure or poor operation of
WWTP leading to poor treatment
performance
The Belo Horizonte Sanitation Plan states
Main causes may be lack of investments
the complete equipment of the sanitation
for implanting interceptors associated to
system in 20 years.
high costs, political and social difficulties
for removing informal settlements from
riparian areas, making difficult interceptors
building.
Main causes:
• Technical difficulties in locating
and reducing that kind of
connexions.
• Need of training and information in
order to avoid new inadequate
connexions between the two
systems.
• Informal settlements (shantytowns)
usually “adopt” combined
sewerage systems.
Although of low risk, changes in policy and
planning may postpone investments in
treatment plants.
The Brazilian Continuous Education
Programme on Water Supply and
Sanitation headed by the UFMG in the
Southeast Region focus on operational
capacity building. COPASA and PBH
are partner of this programme.
COPASA possesses maintenance high
and consistent operational standards.
WWTP not equipped to remove nutrients
(nitrogen and phosphorous) and emerging
polluters as endocrine-disrupting
chemicals.
Emerging polluting chemicals are not
usually monitored in Brazil. Awareness of
the problem is not wide.
34
Risks associated to
the use of BMPs
Failures on flooding control and wet
weather pollution abatement.
Health risks, soil pollution associated to the
use of BMP devices
Reduced public acceptance of BMP
Accidents related
to natural disaster
Disruption of stormwater systems due to
natural hazards like flooding or landslides.
Failures on system
units due to lack of
maintenance or
ageing of
infrastructure and
equipments.
Key units (e.g.: major culvert channels)
may fail due to lack of maintenance or
ageing: structural rupture due to abrasion or
foundation problems
Increasing costs
Increasing costs imposed by different
causes
Main causes:
• Lack of maintenance
• Technology update is not sufficient
• Persistence in using oversimplified
design methods for source control
and other BMP devices
• Failures in controlling
urbanisation, diffuse pollution
sources, including erosion
processes at the catchment scale
• Ignorance or not enough concern
regarding wet weather diffuse
pollution and its impacts on BMP
Possible causes:
• Investment for de modernisation of
ageing systems
• Maintenance costs
• Operational costs: monitoring,
modelling
• Costs imposed by vandalism
The Swormwater Strategic Plan includes a
programme on technology update and on
capacity building focusing on monitoring,
modelling and new technologies, including
BMP. The BH municipality is investing in
environmental education and dissemination
of urban drainage new technologies for a
large public, including river restoration and
BMP. The SWITCH project research and
demonstration activities will certainly
contribute to reduce the mentioned risks.
Emergency plans exist, but there is need of
further developments on prevention and
mitigating action planning to cope with
those kinds of risks.
Maintenance and operational standards are
high and consistent. Nevertheless, a
comprehensive assessment on investment
needs for the modernisation of ageing
systems must be performed. This question
concerns mainly ageing sewerage where
maintenance is less regular then in the case
of the water supply distribution system.
It is part of the Swormwater Strategic Plan
the assessment of alternatives for funding
current stormwater operational actions.
35
System failure
induced
vandalism.
Vandalism leading to system disruption
There is concern on the risk of vandalism
against monitoring equipments (rain
gauges, automatic samplers, data logger
stations, etc) that will be implemented
under the Swormwater Strategic Plan and
the SWITCH demonstration activities.
The BH municipality is investing in
environmental education and dissemination
of urban drainage new technologies for a
large public. This may include information
on equipments implanted in the catchments
and their role, possibly contributing to
vandalism reduction.
36
Risk and uncertainties associated to governance and institutional development
Further than the risks mentioned above, and as part of the reasons for the emergence of those
risks, are institutional and governance issues. This may concern the requirements of integrated
planning and management that must be developed at different territorial and institutional
scales:
• territorial scale: district, city, metropolitan, river basin, state, national;
• water supply and sanitation sub-sectors: water supply, wastewater, storm water, solid
waste
• sectors of the urban policy development: urban planning, urban development major
projects, housing, industrial development, road system and transport
For part or those sectors, water issues are not currently included in the decision-making
procedures or in the legislation. The implementation of an effective integrated urban water
management system will, therefore, require considerable improvements on governance and
institutional development, in order to ensure effective co-operation among different sectors of
decision-making, policy formulation and management at the urban sphere as well as at the
river basin sphere.
As part of the required institutional development for integrated urban water management is
capacity building. IUWM implementation implies on considerable changes on technical and
managerial methods, including monitoring, modelling, planning, decision-making on the base
of indicators, adopting new legislation, communication, facilitating public participation, etc.
Those changes require well-trained professionals on new methods and techniques, which will
require training of existing staff as well as hiring new professionals.
Therefore, uncertainties and risks related to governance and institutional development refer
mainly to concerns on the difficulties of implementing those new policies, methods and legal
basis.
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38