Use of GIS to Estimate Socioeconomic Losses Caused by Urban Floods: A Tool …
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region of the city of Curitiba (PR). The main water body in the basin is Ribeirão
dos Padilhas. It was chosen because it is the body that receives rainwater from the
hydrographic basin and because it covers a large part of its extension in the open,
contradicting the reality of water bodies in urban centers.
3.1 Hydrological and Hydraulic Study
To estimate the flow of the water body in question, historical data on the intensity,
duration, frequency and distribution of rainfall across the hydrographic basin were
used, over a period of ten years (2008–2018), obtained on the Internet portal of
the Instituto das Waters of Paraná. It is also noteworthy to carry out an on-site
visit to the Hydrographic Basin and to monitor the entire length of Ribeirão dos
Padilhas to observe the water drainage channel and its surroundings for the adoption
of parameters used in the computational modeling equations.
Thus, the hydraulic study was carried out to determine the peak flow, the Concentration Time (Kirpich and Ribeiro methods), the Surface Flow coefficient and the
Full Flow (Rational Method and I-pai-wu Method), considering a recurrence time of
100 years, thus portraying the worst situation to be faced (TUCCI 2007).
The peak flow adopted was 186.50 m
3 /s, for a concentration time of 166.54 min.
Also noteworthy is the calculation of the superficial runoff of the Canal, which
according to Arcement and Schneider (1989), it is possible to determine the roughness
coefficient based on Cowan’s equation (1956), resulting in the coefficients of 0.037
for channel stretches (channeled totally or partially) and 0.084 stretches of plain
(natural runoff).
3.2 Computational Procedures
The geopolitical division data of the municipality (IPPUC 2018), the hydrological
cartography data and the Digital Elevation Model (Suderhsa 2000) used in this
work were all acquired in vector format, which facilitated their organization and
processing. They were initially manipulated in the GIS ArcGIS
® , with the objective
of organizing the information related to the Hydrographic Basin and grouping them
in a single spatial reference system.
The next step involved the use of the HEC-GeoRAS software, a set of procedures,
tools and computational utilities for processing hydraulic and hydrological data with
geospatial reference and integrated in ArcGIS
® . The HEC-GeoRAS is used to draw
the geometry of the water flow structures in the rivers and channels of the study area,
and thus can be worked on later in the simulation of this flow in a computational
environment of the HEC-RAS.
647
region of the city of Curitiba (PR). The main water body in the basin is Ribeirão
dos Padilhas. It was chosen because it is the body that receives rainwater from the
hydrographic basin and because it covers a large part of its extension in the open,
contradicting the reality of water bodies in urban centers.
3.1 Hydrological and Hydraulic Study
To estimate the flow of the water body in question, historical data on the intensity,
duration, frequency and distribution of rainfall across the hydrographic basin were
used, over a period of ten years (2008–2018), obtained on the Internet portal of
the Instituto das Waters of Paraná. It is also noteworthy to carry out an on-site
visit to the Hydrographic Basin and to monitor the entire length of Ribeirão dos
Padilhas to observe the water drainage channel and its surroundings for the adoption
of parameters used in the computational modeling equations.
Thus, the hydraulic study was carried out to determine the peak flow, the Concentration Time (Kirpich and Ribeiro methods), the Surface Flow coefficient and the
Full Flow (Rational Method and I-pai-wu Method), considering a recurrence time of
100 years, thus portraying the worst situation to be faced (TUCCI 2007).
The peak flow adopted was 186.50 m
3 /s, for a concentration time of 166.54 min.
Also noteworthy is the calculation of the superficial runoff of the Canal, which
according to Arcement and Schneider (1989), it is possible to determine the roughness
coefficient based on Cowan’s equation (1956), resulting in the coefficients of 0.037
for channel stretches (channeled totally or partially) and 0.084 stretches of plain
(natural runoff).
3.2 Computational Procedures
The geopolitical division data of the municipality (IPPUC 2018), the hydrological
cartography data and the Digital Elevation Model (Suderhsa 2000) used in this
work were all acquired in vector format, which facilitated their organization and
processing. They were initially manipulated in the GIS ArcGIS
® , with the objective
of organizing the information related to the Hydrographic Basin and grouping them
in a single spatial reference system.
The next step involved the use of the HEC-GeoRAS software, a set of procedures,
tools and computational utilities for processing hydraulic and hydrological data with
geospatial reference and integrated in ArcGIS
® . The HEC-GeoRAS is used to draw
the geometry of the water flow structures in the rivers and channels of the study area,
and thus can be worked on later in the simulation of this flow in a computational
environment of the HEC-RAS.