Diseño de Alcantarillado Pluvial
Urbano: Integración de Tecnologías Convencionales y Sostenibles en Puerto
Villamil, Galápagos
Giancarlo Bravo*
Karla Bravo*
Clemencia Coello[*]
ABSTRACT
Isabela
Island faces stormwater management challenges due to its topography and extreme
weather events. This study was conducted to design an efficient and sustainable
stormwater drainage system for Puerto Villamil, with the aim of preventing
sanitary sewer system overload and reducing environmental impact. The design
was developed using hydraulic calculations in spreadsheets, validated with SWMM
software, and took into account technical standards and local conditions.
Nature-based solutions such as permeable pavements, tree pits, and rain gardens
were incorporated. The final design included 136 pipes, 136 manholes, and 3
outfalls, with 2.12 ha allocated to Sustainable Urban Drainage Systems (SUDs).
Runoff volume was reduced by 38%, and pipe diameters and excavation volumes
were optimized. The project represents an innovative alternative for water
management in protected areas, aligned with SDGs 6, 11, and 14.
Keywords:
Stormwater drainage, runoff, sustainability, hydraulic design, SUDs.
RESUMEN
La Isla Isabela, enfrenta
problemas de gestión pluvial debido a su topografía y eventos climáticos
extremos. Este trabajo se realizó para diseñar un sistema de alcantarillado
pluvial eficiente y sostenible para Puerto Villamil, con el fin de evitar la saturación
del alcantarillado sanitario y reducir el impacto ambiental. El diseño se
elaboró mediante diseños hidráulicos en hojas de cálculo, validados con el
software SWMM, considerando normas técnicas y condiciones locales. Se
incorporaron soluciones basadas en la naturaleza como pavimentos permeables,
alcorques y jardines de lluvia. El diseño final incluyó 136 tuberías, 136 pozos
y 3 descargas, con una asignación de 2,12 ha a Sistemas Urbanos de Drenaje
Sostenible (SUDs). Donde se redujo 38% el volumen de escorrentía se optimizo
diámetros y excavaciones. El proyecto representa una alternativa innovadora
para la gestión del agua en zonas protegidas, alineada con los ODS 6, 11 y 14.
Palabras clave: Alcantarillado pluvial,
escorrentía, sostenibilidad, diseño hidráulico, SUDs.
INTRODUCTION
Stormwater management is essential in urban
environments due to the challenges posed by runoff. Uncontrolled accumulation
of rainwater can cause significant impacts on ecosystems, including flooding,
sewer system saturation, soil erosion, and water body contamination (Kravchenko
et al., 2024a).
Globally, in areas with high anthropogenic activity,
stormwater infiltration can introduce a variety of contaminants into
underground aquifers, such as nutrients, heavy metals, and organic compounds.
These contaminants not only accumulate but also interact in the subsurface,
forming even more harmful secondary pollutants (Karamoutsou et al., 2024).
The mobilization of toxic substances during the
infiltration process can compromise groundwater quality, making the
implementation of sustainable urb n drainage systems crucial to mitigate these
risks and protect both water resources and public health (Dong et al., 2024).
In the context of extreme weather events, sustainable
stormwater management becomes even more relevant. It is essential to reduce
runoff volume, improve water quality, and provide additional benefits to the
quality of urban environments, while promoting biodiversity conservation
(Karamoutsou et al., 2024).
Collecting data on precipitation frequency and runoff
magnitude enables the analysis of water behavior under different climate
scenarios, which is key to designing effective management strategies.
Projections of water volumes to be managed help prevent flooding and alleviate
pressure on existing drainage systems (Yang et al., 2024).
Advanced tools
for generating geographic and hydrological models enable the identification of
critical areas for designing more efficient and sustainable systems. This
approach, based on reliable data, ensures that the stormwater drainage network
is effective, cost-efficient, and resilient to climate and urban changes (Senes
et al., 2021).
Data analyzed prior to the design of the stormwater
drainage network allows the proposal to be adapted to the specific conditions
of each urban area. Knowledge of precipitation, topography, and land use
improves the capacity to manage water flow, reducing the risk of flooding and
overflows (Allende-Prieto et al., 2018).
The Galápagos Islands, located in the Ecuadorian
Pacific Ocean, have a subtropical climate with a wet and a dry season,
influenced by the Humboldt Current. The islands are characterized by young
volcanic soils with low organic fertility. Geographically, the islands feature
a wide variety of habitats due to their volcanic origin. Isabela Island, the
largest in the archipelago, stands out for its ecological diversity and active
volcanoes such as Sierra Negra and Alcedo. Its rich biodiversity makes it a crucial
focus for conservation, facing challenges such as mass tourism and invasive
species (Maestro, M.; Pérez-Cayeiro, M.L.; Reyes, H.; Chica-Ruiz, J.A., 2024).
Isabela Island has a tropical marine climate with
stable temperatures and significant seasonal variations. The rainy season, from
December to May, brings frequent rainfall that can affect the sewer
infrastructure, while the dry season, from June to November, presents water
supply challenges (Alzueta Pérez, 2014).
In addition, El Niño and La Niña phenomena introduce
interannual variability, influencing precipitation levels and, consequently,
resource management and the sustainability of the sewer system. Adaptive
planning is crucial for mitigating climate impacts (Burbano, D.V. et al.,
2022).
The Isabela Land Use and Development Plan indicates
that the existing sanitary sewer system discharges into a deficient pumping
station, which becomes overloaded during rains, causing collapses and
uncontrolled discharges into water sources such as the Poza de los Flamingos
lagoon (Municipal Decentralized Autonomous Government of Isabela, 2023).
Therefore, it is necessary to propose alternative
construction solutions to conventional open-trench technology, given the high
complexity of the rocky soil. These stormwater management alternatives aim to
address surface runoff, the risk of flooding due to waterlogging, and various
types of pollution.
The project’s objectives include determining baseline
data for an alternative and sustainable solution, analyzing various
construction alternatives, and developing a detailed design for the stormwater
drainage network, including plans, technical specifications, and a budget. This
comprehensive approach seeks not only to resolve technical problems but also to
protect public health and the environment of Santa Isabela, contributing to the
sustainability of the Galápagos Islands.
Stormwater management in urban areas depends on an
understanding of key hydrological parameters, such as rainfall intensity,
runoff coefficient, and Intensity–Duration–Frequency (IDF) curves, which allow
for the estimation of peak flow using the rational method. These fundamentals
are essential for designing hydraulic infrastructure that reduces flood risk
and optimizes water resource management (Xiao & Vasconcelos, 2023; Diogo
& do Carmo, 2019).
In recent decades, urban water management has evolved
toward more sustainable approaches, such as Sustainable Urban Drainage Systems
(SUDS), which integrate nature-based solutions—permeable pavements, rain
gardens, and vegetated swales—to reduce runoff and improve water quality.
International experiences, such as sponge cities in China, demonstrate
reductions of up to 90% in runoff volume through hybrid strategies that combine
green and gray infrastructure (Grigg, 2024; Wang et al., 2024; Zhang et al., 2021).
Various studies in Latin America and Europe have shown
that combining conventional systems with sustainable solutions improves
hydraulic efficiency and resilience to extreme rainfall. In Brazil and Costa
Rica, the implementation of hybrid bio-retention and underground storage
systems has significantly reduced surface runoff, demonstrating the
applicability of SUDS in tropical contexts (Bouarafa et al., 2019; Chapa et
al., 2020).
Among the most effective technologies are permeable
pavements, which allow for infiltration and aquifer recharge; structural tree
pits, which combine vegetation and contaminant retention; and rain gardens,
which reduce nutrients and suspended solids in urban water. These solutions
provide not only hydrological benefits but also environmental and social ones,
such as improved landscape and urban health (Hu et al., 2018; Lim et al., 2021;
Jeon et al., 2021).
Urban drainage design requires integrating
hydrological and hydraulic aspects with economic viability criteria,
considering both capital (CAPEX) and operating (OPEX) costs. Recent studies
show that, although SUDS may have a higher initial cost, they offer significant
long-term returns by reducing maintenance expenses and flood damage
(García-Haba et al., 2023; Sulis et al., 2024).
Finally, in the Ecuadorian context, regulations for
the Galápagos promote the incorporation of sustainable urban drainage
technologies, prioritizing environmental protection and resilience to climate
change. This regulatory framework provides a basis for the design of
infrastructure adapted to island and sensitive environments (Ragazzi et al.,
2016; Francisco et al., 2023).
MATERIALS AND METHODS
The methodology employed in this project follows a
Traditional or Sequential approach, where each stage of the process is carried
out in a sequential and orderly manner. The flowchart is shown below inFigure¡Error! No hay texto con el estilo especificado en el documento.. :
Figure¡Error! No hay
texto con el estilo especificado en el documento.. Flowchart of
the project methodology [Author’s own work]
Phase 1: Data Collection and Meteorological Analysis.
The first phase of the project begins with a
comprehensive review of the existing literature on stormwater drainage system
design to establish a solid theoretical framework. Next, meteorological and
topographic data crucial for the design of the stormwater drainage system in
Santa Isabela are collected. This includes gathering data that serves as a
foundation for the project, as well as an initial assessment of the problem.
Phase 2: Hydrological Design.
In this phase, the design flow rates necessary to
handle the expected water volume during rainfall events are calculated. Using
the previously collected meteorological and topographical information, the
characteristics of water flow on the island are analyzed to ensure that the
stormwater drainage system is capable of effectively managing runoff.
Additionally, the micro-watershed, water flow direction, and land use are
defined, taking into account the terrain characteristics to optimize the system
design. This comprehensive assessment allows the design to be adapted to the
specific conditions of Santa Isabela, ensuring efficient stormwater management
and the prevention of flooding problems.
Phase 3: Evaluation of Alternatives and Design.
For this phase, comparative analyses are conducted to
identify which of the proposed alternatives best optimizes stormwater
management, considering technical, economic, environmental, and social factors.
Based on the data obtained in the previous phases, the selected alternative for
the stormwater drainage system is designed, evaluating its hydraulic efficiency
and its adaptation to the terrain.
Phase 4: Documentation
Finally, the unit price analysis (UPAs), the detailed
budget, and the costed project schedule are prepared. In addition, the
corresponding technical specifications and detailed drawings of the storm sewer
system are prepared, including the final design of the structures and their
layout on-site.
The laboratory or desk work will involve processing
the collected data and analyzing it for the design of the stormwater drainage
system:
Meteorological Data Analysis: For the analysis of
meteorological data, INAMHI’s IDF curves for San Cristóbal will be used due to
the lack of specific data for Santa Isabela. Although San Cristóbal and Santa
Isabela are separate islands, they share similar climatic and meteorological
conditions due to their geographical proximity within the Galápagos
Archipelago. This similarity in precipitation patterns makes the San Cristóbal
IDF curves a reasonable representation of conditions in Santa Isabela. The absence
of specific local meteorological data necessitates the use of the closest
available data, and the use of San Cristóbal’s IDF curves will allow for an
adequate estimation of flood risk, which is crucial for designing an effective
drainage system in Santa Isabela. In previous studies, the application of
meteorological data from a neighboring island has proven to be sufficiently
accurate for the planning and design of drainage systems in the region.
Topographic Data Study: The digital terrain models
(DTMs) provided by GAD Isabela, along with NASA’s Digital Elevation Models
(DEMs)Figure¡Error! No hay texto con el estilo especificado en el documento.. , were used
to obtain high-precision topographic data for the study area. These data were
essential for generating surfaces and defining the drainage area. They were
analyzed to calculate the catchment area, perform terrain slope calculations,
and verify the accuracy of the topographic measurements. Additionally, these
models made it possible to determine runoff areas and analyze water behavior
during rainfall events, which was key to the design of the stormwater drainage
system.
Figure¡Error! No hay texto con el estilo especificado en el documento.. Earth Data
Platform, topographic data extraction [NASA Alaska Satellite Facility,
2024]
Design period: For theTable
1 , the
design period must be selected taking into account the type of system and the
drainage area, as these factors are fundamental to ensuring the system’s
durability and efficiency. Considering these variables ensures that the system
is adequately adapted to water management conditions and expected extreme
events.
Table 1.
Design periods according to
|
System Type |
Pipe Type |
Drainage area |
T return [years] |
|
Micro-drainage |
Residential,
commercial |
<=2 |
2–5 |
|
Pipes in
any area |
>10 |
10 |
|
|
Pipes in any
area |
>10 |
10 |
|
|
Macro drainage |
Concrete
channels and vegetation |
<=1000 |
10–25 |
|
Concrete
channels |
>1000 |
10 |
|
|
Mixed
concrete and vegetation channels |
50 |
||
|
Channels
including the free edge |
100 |
Land Use Analysis Using ESA Software: Software from
the European Space Agency (ESA) was used to obtain detailed information on land
use in the study area. These data were used to determine the runoff
coefficient, a fundamental parameter in the design of stormwater drainage
systems. Runoff Coefficient: The EMAAP-Q (2009) runoff coefficient table was
used to determine the appropriate values based on surface characteristics and
return period.
Hydraulic Equations: Hydraulic equations were used to
determine the behavior of water flow in a pipe section. The data were obtained
from the technical literature, specifically from the work of López Cualla
(2000).
Velocity Ranges and Roughness Coefficient: CPE INEN
9-1 establishes that the velocity in the pipe must not be less than 0.45 m/s to
prevent the retention of solids, and a velocity of 0.60 m/s is recommended.
Shear Stress: The self-cleaning condition must be
verified for each section of the network, where the average shear stress must
be at least 1 Pa, according to EMAAP-Q (2009).
The information collected in the previous phases of
the project will be tabulated for analysis and subsequent application in the
design of the stormwater drainage system.
IDF Curves: The Intensity-Duration-Frequency (IDF)
curves for San Cristóbal, will be used as the basis for flow calculations. This
data will be tabulated to show the different rainfall intensities according to
the return period and the duration of the rainfall event.
Topographic data: Digital elevation models (DEM) and
terrain slope data will be used for processing in geographic information
systems. These data will enable the delineation of micro-watersheds and the
identification of runoff areas. Runoff coefficients: The runoff coefficients to
be used will be tabulated and land uses will be plotted
Table ¡Error! No hay texto con el estilo
especificado en el documento. .
Runoff coefficient values [EMAAP-Q, 2009]
|
VALUES USED TO DETERMINE A
RUNOFF COEFFICIENT BASED ON SURFACE CHARACTERISTICS |
||||
|
Area Description |
Return Period (years) |
|||
|
2 |
5 |
10 |
||
|
Asphalt |
0.73 |
0.77 |
0.81 |
|
|
Concrete / Roof |
0.75 |
0.8 |
0.83 |
|
|
Green areas (gardens, parks,
etc.), 50% of the area covered with grass |
||||
|
- Slope 0–2% |
0.32 |
0.34 |
0.37 |
|
|
- Average 2–7% |
0.37 |
0.4 |
0.43 |
|
|
- Grade greater than 7% |
0.40 |
0.43 |
0.45 |
|
|
Grasslands |
||||
|
- Flat 0–2% |
0.25 |
0.28 |
0.3 |
|
|
- Average 2–7% |
0.33 |
0.36 |
0.38 |
|
|
- Grade greater than 7% |
0.37 |
0.4 |
0.42 |
|
Hydraulic parameters: The hydraulic relationships and
maximum velocities will be presented in tables to ensure that the system meets
the necessary hydraulic criteria to prevent problems such as sediment
accumulation in the pipes.
|
|
|
|
|
|
|
0.01 |
0.292 |
0.092 |
0.239 |
0.041 |
|
0.02 |
0.352 |
0.124 |
0.315 |
0.067 |
|
0.03 |
0.040 |
0.148 |
0.370 |
0.086 |
|
0.04 |
0.427 |
0.165 |
0.410 |
0.102 |
|
0.05 |
0.453 |
0.182 |
0.449 |
0.116 |
|
0.06 |
0.473 |
0.196 |
0.481 |
0.128 |
|
0.07 |
0.492 |
0.210 |
0.510 |
0.140 |
|
0.08 |
0.505 |
0.220 |
0.530 |
0.151 |
|
0.09 |
0.520 |
0.232 |
0.554 |
0.161 |
|
0.10 |
0.540 |
0.248 |
0.586 |
0.170 |
|
0.11 |
0.553 |
0.258 |
0.606 |
0.179 |
|
0.12 |
0.570 |
0.270 |
0.630 |
0.188 |
|
0.13 |
0.580 |
0.280 |
0.650 |
0.197 |
|
0.14 |
0.590 |
0.289 |
0.668 |
0.213 |
|
0.15 |
0.600 |
0.298 |
0.686 |
0.213 |
RESULTS
This section details the layout of the traditional
sewer system and the area where sustainable drainage systems (SUDs) will be
implemented in Puerto Villamil, as shown in the¡Error!
No se encuentra el origen de la referencia. . The
layout of the pipes will be based on the local topography, using the following
criteria:
Installation depth: The minimum depth will be 1.2
meters; installation at a shallower depth may be considered in certain areas
using appropriate backfill. Efforts will be made not to exceed 4 meters to
control costs.
Minimum slope: A minimum slope of 0.5% will be
established to ensure efficient stormwater flow.
Runoff coefficient and
catchment area per manhole
|
Well 17 |
|||||
|
Catchment |
Area [ha] |
Runoff coefficient |
Street length [m] |
Longitudinal slope [%] |
Road width [m] |
|
1 |
0.131 |
0.78 |
70.1 |
0.3 |
6 |
|
2 |
0.118 |
0.78 |
72.52 |
0.3 |
7 |
|
3 |
0.404 |
0.52 |
147.31 |
0.3 |
7 |
|
Table¡Error! No hay texto con el estilo especificado en el
documento. .2 Description of Well 17 [Author’s own work] |
Using the land use data shown in¡Error!
No se encuentra el origen de la referencia. and fromTable
¡Error! No hay texto con el estilo especificado en el documento.
.
Runoff coefficient values [EMAAP-Q, 2009]Table
¡Error! No hay texto con el estilo especificado en el
documento. . , the
runoff coefficients are obtained. For this example, well 17, which feeds into
pipe 16, will be used.
Travel time
Using the equation(1 , the
travel time is calculated using an initial velocity of 1.2 m/s.
|
(1 ) |
|
C0 |
C4 |
C6 |
C8 |
|
Contribution |
Length |
Speed |
Time elapsed |
|
243 |
70.10 |
1.20 |
0.97 |
|
229 |
72.52 |
1.20 |
1.01 |
|
222 |
147.31 |
1.20 |
2.05 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.3 Travel time [Author’s own work]
From
Equation 2, the concentration time (tc) is determined by combining the initial
time (ti) and the travel time (tr), assuming an initial time of 10 minutes.
|
|
|
(2 ) |
|
C0 |
C8 |
C9 |
|
Contribution |
Time elapsed |
Concentration
time |
|
243 |
0.97 |
10.97 |
|
229 |
1.01 |
11.01 |
|
222 |
2.05 |
12.05 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.4 Concentration time [Author’s own work]
|
C2 |
C10 |
C11 |
|
|
Contribution |
Area |
Retention
period |
Intensity |
|
243 |
0.13 |
5.00 |
66.20 |
|
229 |
0.12 |
5.00 |
66.13 |
|
222 |
0.40 |
5.00 |
64.12 |
Rainfall
intensity
Using the formulas derived from the IDF curves (¡Error!
No se encuentra el origen de la referencia. equation),
rainfall intensity (I) is calculated assuming a 5-year return period.
|
|
|
(3 ) |
¡Error! No hay texto con el estilo especificado en el
documento. Table.5 Rainfall intensity [Own elaboration]
Using the Rational Method equation(4 , the
design flow (QDis) is determined by considering a runoff coefficient (C) that
depends on factors such as land cover and slope.
|
|
|
(4 ) |
|
C0 |
C2 |
C11 |
C12 |
|
Contribution |
Area |
Intensity |
Flow |
|
243 |
0.13 |
66.20 |
18.74 |
|
229 |
0.12 |
66.13 |
16.85 |
|
222 |
0.40 |
64.12 |
37.69 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.6 Design flow rate [Own work]
The actual head in the ditch (y) is calculated using
Manning’s simplified formula for ditches, in which the depth value must be
solved for, as shown in equation(5 .
|
|
(5 ) |
|
C0 |
C5 |
C12 |
C29 |
C30 |
C20 |
|
Contribution |
Flow |
Flow |
n |
Z |
and |
|
243 |
0.003 |
18.74 |
0.02 |
50.00 |
4.98 |
|
229 |
0.003 |
16.85 |
0.02 |
50.00 |
4.77 |
|
222 |
0.003 |
37.69 |
0.02 |
50.00 |
6.38 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.7 Actual tension at the curb [Author’s own work]
The wet width (T) is calculated as the product of the
depth (y) and the inverse of the cross-slope (Z), using the equation(6 :
|
|
(6 ) |
|
C0 |
C20 |
C30 |
C21 |
|
Contribution |
and |
Z |
T |
|
243 |
4.98 |
50.00 |
248.79 |
|
229 |
4.77 |
50.00 |
238.57 |
|
222 |
6.38 |
50.00 |
318.86 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .8 Wet width [Author's own compilation]
The cross-sectional area (Atransversal ) is calculated
using the equation(7 :
|
|
(7 ) |
|
C0 |
C12 |
C23 |
C22 |
|
Flow |
Flow |
Atrans |
V Actual |
|
243 |
18.74 |
0.066 |
0.30 |
|
229 |
16.85 |
0.061 |
0.30 |
|
222 |
37.69 |
0.112 |
0.37 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.9 Cross-sectional area [Author’s own work]
The flow velocity (v) is calculated using the
relationship between the flow rate (Q) and the cross-sectional area (A),
according to the equation(8 :
|
|
(8 ) |
|
C0 |
C20 |
C21 |
C23 |
|
Contribution |
and |
T |
Atrans |
|
243 |
4.98 |
248.79 |
0.066 |
|
229 |
4.77 |
238.57 |
0.061 |
|
222 |
6.38 |
318.86 |
0.112 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .10 Flow velocity [Author’s own work]
Now, using this calculated velocity, the travel time,
residence time, concentration, and flow rate are recalculated.
|
C0 |
C24 |
C25 |
C26 |
C27 |
|
Contribution |
t distance |
t concentration |
Intensity |
Flow |
|
243 |
3.86 |
13.86 |
61.12 |
17.31 |
|
229 |
4.08 |
14.08 |
60.79 |
15.49 |
|
222 |
6.62 |
16.62 |
57.44 |
33.77 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.11 Values corrected with the new travel speed [Author’s
own work]
The control tie (yco) is calculated using the ratio of
the critical tie (Tco) to the inverse of the cross-slope (Z), using the
equation(9 :
|
|
(9 ) |
|
C0 |
C30 |
C37 |
C38 |
|
Contribution |
Z |
Tco |
yco |
|
243 |
50.00 |
350.00 |
7.00 |
|
229 |
50.00 |
300.00 |
6.00 |
|
222 |
50.00 |
350.00 |
7.00 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.12 Control Tie [Own Work]
The drainage capacity (Qs) in a ditch is determined by
applying the(5 flow
equation based on the Manning coefficient and the geometric and hydraulic
parameters:
|
(10 ) |
|
C0 |
C5 |
C29 |
C30 |
C37 |
C38 |
C39 |
|
Contribution |
Pending |
n |
Z |
Tc |
and |
Qs |
|
243 |
0.003 |
0.02 |
50.00 |
350.00 |
7.00 |
42.74 |
|
229 |
0.003 |
0.02 |
50.00 |
300.00 |
6.00 |
28.33 |
|
222 |
0.003 |
0.02 |
50.00 |
350.00 |
7.00 |
42.74 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .13 Drainage capacity [Author's own compilation]
The number of drains required (N) is determined by
dividing the design flow (Qdis) by the drainage capacity of the gutter (Qs),
equation(11 :
|
|
(11 ) |
|
C0 |
C27 |
C39 |
|
Contribution |
Flow |
Qs |
|
243 |
17.31 |
42.74 |
|
229 |
15.49 |
28.33 |
|
222 |
33.77 |
42.74 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.14 Number of sumps [Author’s own work]
Calculation of pipes and wells
As an example, consider pipe 18, which runs from well
19 to well 20.
The concentration time (tc) is determined by combining
the initial time (ti) and the travel time (tr), considering the concentration
time of the previous section as the initial time.
|
C0 |
C5 |
C9 |
C10 |
C11 |
C12 |
|
Home |
Initial |
Assumed |
Estimated |
Calculated |
Calculated |
|
Pipe |
Length |
Velocity |
Concentration
time |
||
|
L_Pipe |
V Test |
T initial |
T elapsed |
Concentration
time |
|
|
[m] |
[m/s] |
[min] |
[min] |
[min] |
|
|
18 |
74 |
2.12 |
19.7 |
0.6 |
20.3 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .15 Initial time, travel time, and concentration time
[Author's own work]
Travel time and concentration time
Travel time (tr) is calculated using Equation (1) with
an initial velocity of 2.12 m/s obtained in Section 3.1.4.10, and concentration
time (tc) is determined as the sum of initial time (ti) and travel time (tr),
according to Equation 2.
Rainfall intensity (III) is calculated using the
formula derived from the IDF curves, Equation 3.
|
C0 |
C10 |
C11 |
C12 |
C13 |
C14 |
|
Initial |
Calculated |
Calculated |
Calculated |
Standardized |
Calculated |
|
Piping |
Concentration
time |
Coefficient |
Rainfall
intensity |
||
|
Initial T |
Travel time |
Concentration T |
Retention
period |
||
|
[min] |
[min] |
[min] |
[Years] |
[mm/hr] |
|
|
18 |
19.7 |
0.6 |
20.3 |
5 |
63.7 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .16 Rainfall intensity [Author’s own compilation]
The cumulative catchment area (AAcumulada) is
calculated by summing the individual areas of each contribution, Equation 5:
|
|
|
(12 ) |
|
C0 |
C6 |
C7 |
|
Initial |
Home |
Initial |
|
Piping |
Area |
|
|
Own |
Cumulative |
|
|
[Ha] |
[ha] |
|
|
18 |
0.57 |
21.95 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.17 Catchment Area [Own work]
The flow rate (Q) is calculated using the Rational
Method formula, Equation(4 :
|
C0 |
C6 |
C7 |
C8 |
C14 |
C18 |
|
Home |
Home |
Initial |
Standard |
Calculated |
Calculated |
|
Piping |
Area |
Coefficient |
Rainfall
intensity |
Flow |
|
|
Instantaneous |
Cumulative |
C (runoff) |
without SUDs |
||
|
[ha] |
[Ha] |
[Dimensionless] |
[mm/hr] |
[L/s] |
|
|
18 |
0.57 |
21.95 |
0.53 |
53.7 |
1742 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .18 Flow [Author’s own work]
Flow infiltrated by the
sustainable drainage system
The infiltrated flow (Qinfil) is calculated by
considering the permeability and area of the sustainable drainage system
(SUDs), using the equation(13 :
|
|
|
(13 ) |
|
C0 |
C15 |
C16 |
C17 |
|
Initial |
Assumed |
Estimated |
Calculated |
|
Piping |
SUDs |
||
|
Permeability K |
SUDs area |
Filtered flow |
|
|
[m/s] |
[ha] |
[L/s] |
|
|
18 |
0.00010 |
0.677 |
676.9 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .19 Infiltration flow through the sustainable drainage
system [Author’s own work]
The design flow (QDis) is calculated by subtracting
the infiltrated flow (Qinfil) from the flow without SUDs (Q), according to the
equation(14 :
|
|
|
(14 ) |
|
C0 |
C17 |
C18 |
C19 |
|
Initial |
Calculated |
Calculated |
Calculated |
|
Piping |
Flow |
Flow |
Flow |
|
filtered |
without SUDs |
Design |
|
|
[L/s] |
[L/s] |
[L/s] |
|
|
18 |
676.9 |
1742.0 |
1065.2 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .20 Design flow rate [Author’s own work]
The required pipe diameter (DDis) is calculated using
Manning’s formula(15 to
determine the hydraulic diameter based on the design flow rate (QDis), the
slope (S), and the roughness coefficient (n).
|
|
|
(15 ) |
|
C0 |
C20 |
C21 |
C22 |
C23 |
C22 |
C23 |
C22 |
C23 |
|
Initial |
Assumed |
Standard |
Calculated |
Calculated |
Calculated |
Calculated |
Assumed |
Assumed |
|
Piping |
Slope |
Manning |
Required diameter |
True required diameter |
Commercial Diameter |
|||
|
S |
Pipe_Diameter |
In meters |
In inches |
Previous sections |
||||
|
[%] |
[s/m^1/3] |
[m] |
[in] |
[m] |
[in] |
[m] |
[in] |
|
|
18 |
0.5 |
0.011 |
0.805 |
31.7 |
34.00 |
0.860 |
36 |
0.91 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.21 Pipe diameter [Own work]
The flow rate (QO) is determined under full-pipe
conditions, considering the adopted diameter and using Manning’s equation(15 7:
|
|
|
(16 ) |
|
C0 |
C28 |
C29 |
C30 |
|
Initial |
Calculated |
Calculated |
Calculated |
|
Pipe |
Solid pipe |
||
|
Rh 0 |
Q_0 |
V_0 |
|
|
[m] |
[L/s] |
[m/s] |
|
|
18 |
0.23 |
1480 |
2.27 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .22 Full-pipe flow (flow rate, hydraulic radius, and
velocity) [Author’s own work]
Full-pipe flow rate, full-pipe hydraulic radius, and
full-pipe velocity
The maximum full-pipe flow rate (Qo) is calculated
using Equation 17, while the full-pipe hydraulic radius is determined using
Equation 18 and the full-pipe velocity is obtained from Equation 19.
|
|
|
(17 ) |
|
|
|
(18 ) |
Hydraulic relationships allow parameters such as flow
rate, velocity, head, and hydraulic radius to be compared with full-pipe
conditions.
|
C0 |
C31 |
C32 |
C33 |
C34 |
C35 |
C36 |
|
Initial |
Calculated |
Table |
Table |
Table |
Table |
Condition |
|
Piping |
Hydraulic
Ratios |
|||||
|
Q/Q_0 |
V/V_0 |
d/D |
R/R_0 |
H/D |
||
|
[Dimensionless] |
[Dimensionless] |
[Dimensionless] |
[Dimensionless] |
[m/s] |
Condition |
|
|
18 |
0.72 |
0.955 |
0.705 |
1.182 |
0.67 |
COMPLIES |
¡Error! No hay texto con el estilo especificado en el
documento. Table.23 Hydraulic relationships [Author’s own work]
|
C0 |
C37 |
C38 |
C39 |
C40 |
C41 |
C46 |
|
Initial |
Calculated |
Condition |
Calculated |
Calculated |
Calculated |
Calculated |
|
Pipe |
Velocity |
T path 2 |
Water depth |
Hydraulic
radius |
Hydraulic depth |
|
|
V |
Corrected |
d |
R |
H |
||
|
[m/s] |
Condition |
[min] |
[m] |
[m] |
[m] |
|
|
18 |
2.17 |
MEETS |
0.6 |
0.64 |
0.27 |
0.58 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.24 Actual flow in the section [Own work]
Velocity
The actual flow velocity is calculated by adjusting
the full-pipe velocity using the corresponding hydraulic ratio, equation¡Error!
No se encuentra el origen de la referencia. . Comparing
with the velocity used at the beginning
|
|
|
|
Water depth, hydraulic radius, and hydraulic depth
The water depth (d) inside the pipe is calculated by
multiplying the design diameter (Dis) by the corresponding hydraulic ratio
(d/D)r, equation¡Error!
No se encuentra el origen de la referencia.
. The hydraulic radius (Rh) is calculated by multiplying the hydraulic radius
for a full pipe (Rh0) by the corresponding hydraulic ratio (R/Ro)r, equation¡Error!
No se encuentra el origen de la referencia. . The
hydraulic depth (H) is calculated by multiplying the required pipe diameter
(DDis) by the corresponding hydraulic ratio (H/D)r,
equation¡Error!
No se encuentra el origen de la referencia. .
|
|
|
||
|
|
|
||
|
|
|
The shear stress (τ)
is calculated using the equation(19 :
|
|
|
(19 ) |
|
C0 |
C20 |
C41 |
C42 |
C43 |
|
Initial |
Assumed |
Calculated |
Calculated |
Condition |
|
Piping |
Slope |
Hydraulic
radius |
Stress |
|
|
S |
R |
Tao |
||
|
[%] |
[m] |
[N/m²] |
Condition |
|
|
18 |
0.5 |
0.27 |
11.9 |
MEETS |
¡Error! No hay texto con el estilo especificado en el
documento. Table.25 Shear stress [Author’s own work]
Velocity
height
The velocity height is calculated using the equation(20 :
|
|
|
(20 ) |
|
C0 |
C37 |
C38 |
C40 |
|
Initial |
Calculated |
Condition |
Calculated |
|
Pipe |
Velocity |
Velocity head |
|
|
V |
(V1^2)/(2*g) |
||
|
[m/s] |
Condition |
[m] |
|
|
18 |
2.17 |
MEETS |
0.24 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.26 Velocity head [Author’s own work]
Specific energy for actual flow
|
|
|
(21 ) |
The specific energy for the actual flow is calculated
by adding the water depth (d) and the velocity head (hV ),
equation(21 :
|
C0 |
C40 |
C40 |
C45 |
|
Initial |
Calculated |
Calculated |
Calculated |
|
Pipe |
Water sheet |
Velocity head |
Energy |
|
d |
(V1^2)/(2*g) |
E |
|
|
[m] |
[m] |
[m] |
|
|
18 |
0.64 |
0.24 |
0.88 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .27 Specific energy for actual flow [Author's own work]
|
|
|
(22 ) |
(22The Froude
number is calculated using the Froude equation:
|
C0 |
C37 |
C46 |
C47 |
C48 |
|
Initial |
Calculated |
Calculated |
Calculated |
Condition |
|
Pipe |
Velocity |
Hydraulic depth |
Froude number |
|
|
V |
H |
NF |
||
|
[m/s] |
[m] |
[Dimensionless] |
Flow type |
|
|
18 |
2.17 |
0.58 |
0.9 |
Subcritical |
Table¡Error! No hay texto con el estilo especificado en el
documento. .28 Froude number [Author’s own work]
|
C0 |
C22 |
C23 |
C19 |
C49 |
C50 |
C51 |
C62 |
C63 |
|
Initial |
Assumed |
Assumed |
Calculated |
Calculated |
Calculated |
Calculated |
Calculated |
Calculated |
|
Pipe |
Nominal
Diameter |
Flow Rate |
Flow ratio |
Critical head |
Critical head |
Critical area |
Critical
velocity |
|
|
Design |
ec |
Yc |
θ |
Ac |
Vc |
|||
|
[m] |
[in] |
[L/s] |
Dimensionless |
[m] |
[°] |
[m²] |
[m/s] |
|
|
16 |
36 |
0.91 |
1065.2 |
0.19 |
0.61 |
3.83 |
0.46 |
0.47 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .29 Flow regime analysis [Author's own work]
Flow ratio, Critical chord, Critical angle, Critical
area, Critical velocity
The flow ratio is calculated using equation (29); from
this, the critical chord length is determined using equation (30), while the
critical angle is obtained using equation (31). Similarly, the critical area is
calculated using equation (32) and the critical velocity is determined using
equation (33).
|
|
|
(23 ) |
|
|
|
(24 ) |
|
|
|
(25 ) |
|
|
|
(26 ) |
|
|
|
(27 ) |
Specific energy for
supercritical flow
(28To calculate
the specific energy for supercritical flow (Ec), the following equation was
used:
|
|
|
(28 ) |
|
C0 |
C49 |
C63 |
C78 |
|
Initial |
Calculated |
Calculated |
Calculated |
|
Pipe |
Critical tie rod |
Critical velocity |
Supercritical in elongated structures
with a drop |
|
Yc |
Vc |
Specific energy for supercritical flow Ec |
|
|
Dimensionless |
[m/s] |
[m] |
|
|
18 |
0.61 |
2.38 |
0.88 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .30 Specific energy for supercritical flow [Author’s own
work]
The equation(29 was used to
calculate the well diameter:
|
|
|
(29 ) |
|
C0 |
C64 |
C67 |
C68 |
C69 |
|
Initial |
Calculated |
Calculated |
Standardized |
Calculated |
|
Pipe |
Pipe diameter Dp_Dis |
Minimum well diameter Dp_min |
Pipe diameter according to NEC |
Adopted well diameter |
|
[m] |
[m] |
[m] |
[m] |
|
|
18 |
0.9 |
0.3 |
0.9 |
1.4 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .31 Well diameter [Own work]
|
|
|
(30 ) |
(30To calculate
the radius of curvature (Rc), the following equation was used:
|
C0 |
C69 |
C70 |
|
Initial |
Calculated |
Calculated |
|
Pipe |
Adopted borehole diameter |
Bend radius rc |
|
[m] |
[m] |
|
|
18 |
1.4 |
4.67 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.32 Radius of curvature [Own work]
|
C0 |
C22 |
C23 |
C19 |
C19 |
C76 |
C77 |
C80 |
||
|
Initial |
Assumed |
Assumed |
Calculated |
Calculated |
Calculated |
Calculated |
Calculated |
||
|
Pipe |
Nominal
Diameter |
Flow |
Increase due to
losses |
Inlet factor Fe |
Head
coefficient kc |
Well head Hc |
|||
|
Design |
Ep |
||||||||
|
[m] |
[in] |
[L/s] |
[m] |
[Dimensionless] |
[Dimensionless] |
[m] |
|||
|
18 |
36 |
0.91 |
1065.2 |
0.04 |
0.43 |
1.40 |
1.29 |
||
Table¡Error! No hay texto con el estilo especificado en el
documento. .33 Well drop [Author’s own work]
Height increase
The equation¡Error!
No se encuentra el origen de la referencia. was used to
calculate the height increase:
Inlet factor
To calculate the head factor, the equation(31 was used:
|
|
|
(31 ) |
|
|
|
|
Well drop height for submerged intake
The well head height was calculated using the equation(32 :
|
|
|
(32 ) |
|
C0 |
C40 |
C65 |
C66 |
C72 |
C73 |
C74 |
C81 |
|
Initial |
Calculated |
Calculated |
Calculated |
Coefficient |
Calculated |
Calculated |
Calculated |
|
Pipe |
(V1^2)/(2*g) |
Transition
coefficient kt |
Transition loss
Ht |
Angle change
coefficient kd |
Angular
velocity loss Hd |
Absolute loss
He |
Head loss Hp |
|
[m] |
[Dimensionless] |
[m] |
[Dimensionless] |
[m] |
[m] |
[m] |
|
|
18 |
0.27 |
Accelerated |
0.002 |
0.05 |
0.012 |
0.014 |
0.65 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .34 Energy losses [Author’s own work]
Transition loss, directional change loss, absolute
loss, and head loss
Hydraulic losses were calculated using the
corresponding equations: transition loss was determined using equation (42),
change-of-direction loss using equation (43), total head loss using equation
(44), and head loss using equation (45).
|
|
|
(33 ) |
|
|
|
(34 ) |
|
|
|
(35 ) |
Elevations and depths for
subsequent sections
Energy level
The energy level (CE) refers to the energy level of
the flow in a section of the piping system (equation¡Error!
No se encuentra el origen de la referencia. ),
considering the head loss due to the slope (S) and the length of the section
(L) equation(36 :
|
|
|
(36 ) |
|
C0 |
C5 |
C20 |
C90 |
C91 |
C92 |
|
Initial |
Initial |
Assumed |
Calculated |
Calculated |
Calculated |
|
Pipe |
Length |
Slope |
Energy level |
||
|
L_Pipe |
S |
From |
A |
Entry to the next section |
|
|
[m] |
[%] |
[m] |
[m] |
[m] |
|
|
18 |
74 |
0.5 |
4.8 |
4.5 |
4.5 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .35 Energy level [Author’s own work]
|
C0 |
C90 |
C91 |
C92 |
|
Initial |
Calculated |
Calculated |
Calculated |
|
Pipe |
Energy rating |
||
|
From |
To |
Entry to the
next section |
|
|
[m] |
[m] |
[m] |
|
|
17 |
5.4 |
4.8 |
4.8 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.36 Energy level of the previous section [Author’s own
work]
Batea elevation
The head (CB) represents the height of the bottom of
the conduit or pipe in terms of total energy (equation(37 ). On the
other hand, considering the slope of the section and the specific energy of the
flow, the final head is calculated using equation(38 :
|
C0 |
C5 |
C20 |
C45 |
C90 |
C86 |
C87 |
|
Home |
Initial |
Assumed |
Calculated |
Calculated |
Calculated |
Calculated |
|
Pipe |
Length |
Slope |
Energy |
Energy
elevation |
Trough
elevation |
|
|
L_Pipe |
S |
E |
From |
From |
A |
|
|
[m] |
[%] |
[m] |
[m] |
[m] |
[m] |
|
|
18 |
74 |
0.5 |
0.88 |
4.8 |
3.9 |
3.6 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .37 Bate height [Author’s own work]
|
|
|
(37 ) |
|
|
|
(38 ) |
Key dimension
|
|
|
(39 ) |
|
|
|
(40 ) |
The key elevation (CC) refers to the height of the
pipe’s top surface above sea level, calculated by adding the pipe’s nominal
diameter to the bench elevation (equation(39 ).
Additionally, considering the slope of the section and the specific energy of
the flow, the final key elevation is calculated (equation(40 ):
|
C0 |
C5 |
C20 |
C22 |
C23 |
C86 |
C87 |
C84 |
C85 |
|
Home |
Initial |
Assumed |
Assumed |
Assumed |
Calculated |
Calculated |
Calculated |
Calculated |
|
Pipe |
Length |
Slope |
Commercial Diameter |
Trough elevation |
Key elevation |
|||
|
L_Pipe |
S |
From |
To |
From |
To |
|||
|
[m] |
[%] |
[m] |
[in] |
[m] |
[m] |
[m] |
[m] |
|
|
18 |
74 |
0.5 |
36 |
0.91 |
3.9 |
3.6 |
4.9 |
4.5 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .38 Key elevation [Author’s own work]
Water Level
The water depth (CL) is the level at which the water
surface is located inside the pipe. It is calculated by adding the water depth
(d) to the initial water depth, as shown in equation(41 . On the
other hand, considering the slope of the section and the specific energy of the
flow, the final water depth is calculated using equation(42 :
|
|
|
(41 ) |
|
|
|
(42 ) |
|
C0 |
C5 |
C20 |
C40 |
C86 |
C87 |
C88 |
C89 |
|
Home |
Initial |
Assumed |
Calculated |
Calculated |
Calculated |
Calculated |
Calculated |
|
Pipe |
Length |
Slope |
Water depth |
Trough level |
Water depth |
||
|
L_Pipe |
S |
d |
From |
To |
From |
To |
|
|
[m] |
[%] |
[m] |
[m] |
[m] |
[m] |
[m] |
|
|
18 |
74 |
0.5 |
0.64 |
3.9 |
3.6 |
4.6 |
4.3 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .39 Water level [Author’s own compilation]
Key elevation depth
The depth of the reference level (PCC) represents the
vertical distance between the ground level (CR) and the reference level (CC) of
the pipe. Equations(43 -(44 :
|
|
|
(43 ) |
|
|
|
(44 ) |
|
C0 |
C82 |
C83 |
C84 |
C85 |
C93 |
C94 |
|
Initial |
Calculated |
Calculated |
Calculated |
Calculated |
Calculated |
Calculated |
|
Piping |
Ground level |
Key elevation |
Depth to key elevation |
|||
|
From |
To |
From |
To |
From |
To |
|
|
[m] |
[m] |
[m] |
[m] |
[m] |
[m] |
|
|
18 |
6.8 |
6.4 |
4.9 |
4.5 |
1.94 |
1.87 |
¡Error! No hay texto con el estilo especificado en el
documento. Table.40 Key depth [Author’s own work]
Pipe bed depth
The backfill depth (PCb) represents the vertical
distance between the ground level (CR) and the backfill level (CB) of the pipe.
Equations(45 -(46 :
|
|
|
(45 ) |
|
|
|
(46 ) |
|
C0 |
C82 |
C83 |
C86 |
C87 |
C95 |
C96 |
|
Initial |
Calculated |
Calculated |
Calculated |
Calculated |
Calculated |
Calculated |
|
Piping |
Ground level |
Formwork level |
Depth to formwork level |
|||
|
From |
To |
From |
To |
From |
To |
|
|
[m] |
[m] |
[m] |
[m] |
[m] |
[m] |
|
|
18 |
6.8 |
6.4 |
3.9 |
3.6 |
2.85 |
2.78 |
Table¡Error! No hay texto con el estilo especificado en el
documento. .41 Depth of the battens [Author's own work]
Table¡Error! No hay
texto con el estilo especificado en el documento..49 Results for pipes 1 through
136 [Author’s own work]
To ensure the project’s success and proper
implementation, it is essential to conduct additional studies to supplement the
information used during the design phase. Among these, detailed studies of soil
characteristics in Puerto Villamil are particularly important, as local
conditions could differ significantly from those assumed in the project.
Likewise, it is essential to develop IDF curves specific to the area, as those
from Santa Cruz Island were used, which introduces uncertainty into the
design’s hydrological parameters.
The budget and schedule presented in this project are
for reference only and must be adjusted during the execution phase. It is
recommended to consider additional factors such as the logistics associated
with transporting materials to the island, the availability of skilled labor,
and other indirect costs that may arise. It is also crucial to include a
detailed analysis of environmental aspects, such as impact mitigation during
construction and operation, as well as the environmental permits necessary to
comply with current regulations and protect the island’s unique biodiversity.
Furthermore, it is suggested to plan for construction
waste management and the restoration of affected areas to minimize the impact
on local ecosystems. Coordination with local and national entities to secure
funding, permits, and technical support will be essential to ensure the
project’s long-term viability.
Finally, it is advisable to develop a continuous
monitoring system that allows for the evaluation of the stormwater system’s
performance and the adjustment of its operation according to changing
environmental conditions. This monitoring, along with the updating of
hydrological and geotechnical data, will contribute to maintaining the system’s
sustainability and effectiveness over time.
CONCLUSIONS
An analysis of the proposed system was conducted,
achieving a 38% reduction in total runoff volume, which allowed for a reduction
in excavation depths and the required pipe diameters. This optimized design
resulted in the installation of 136 pipes, 136 manholes, and 3 outfalls, of
which 4 manholes will require specific drop structures for proper operation.
The system layout was modeled using the open-source
software SWMM, where it was verified that it meets the pipe capacity,
velocities, and head required for proper operation. The average values obtained
for these parameters are a 0.60 m H/D ratio, a 1.3 m/s velocity, and a 5.7 Pa
head, thus ensuring that the design meets hydraulic efficiency standards.
The total area designated for Sustainable Urban
Drainage Systems (SUDs) covers 2.12 hectares, within which solutions such as
permeable pavements, structural tree pits, rain gardens, and green swales were
implemented, contributing to environmental sustainability and efficient
stormwater management.
The total project budget amounts to $3,935,474.73,
distributed as follows: 39% allocated to the purchase and installation of
pipes, 30% allocated to the development and implementation of SUDs, and 25%
allocated to earthwork activities. This breakdown demonstrates a balanced
approach between traditional infrastructure and sustainable solutions.
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Superior Politécnica del litoral, Guayaquil Ecuador, bravo@espol.edu.ec, https://orcid.org/0009-0004-8192-245X
* Arch. Quevedo State Technical University,
kbravoc5@uteq.edu.ec, https://orcid.org/0000-0003-3253-187X
* Ph.D. Quevedo State Technical University,
Ccoello@uteq.edu.ec https://orcid.org/0000-0002-6251-9233