Assessment of Human Stability in Sewer Systems during Dry Weather Conditions
Abstract
:1. Introduction
- The “Technical guide on sanitation and urban drainage networks” of the CEDEX (Centro de Estudios y Experimentación de Obras Públicas or Centre for Studies and Experimentation of Public Works in English), depending on the Spanish Ministry of Development establishes as a definition of visitable collectors those with a minimum height of 160 cm and minimum width of 60 cm [10].
- The Barcelona City Council differentiates three levels of visitable drainage networks: visitable (height or diameter ≥150 cm and width ≥60 cm), semivisitable (height or diameter ≥100 cm and width ≥50 cm) and nonvisitable (height or diameter <100 cm or width <50 cm) [11].
- In the Madrid region, norms about sewer networks elaborated by Canal de Isabel II consider as nonvisitable pipes all the sewers with a height <180 cm. Pipes with a height ≥180 cm could be considered visitable only if they have a separate footpath from the wastewater flow circulating in a gutter or in case flow conditions support a flow depth ≤9 cm and a flow velocity ≤1.5 m/s [12]. This reference is the only one establishing geometric and flow criteria to define visitable sewer pipes.
- The company Lyonnaise des Eaux (France) uses these levels: visitable (height or diameter ≥160 cm), semivisitable (height between 120 and 160 cm) and nonvisitable (height <120 cm) [13].
- ATCO (Asociación de Fabricantes de Tubos de Concreto, in English Association of Concrete Pipe Manufacturers, Mexico) sets the visitable threshold of a circular collector at a diameter greater than 800 mm [13].
- The manual of urban drainage of the Ministry of Public Works of Chile considers sewers visitable if their diameter is at least 160 cm [14].
2. Materials and Methods
2.1. Description of the Case Study
2.2. Hazard Criteria Adopted for Human Stability Assessment
- In their experimental campaigns, a model representing an urban street in real scale was designed and built, using factory and concrete materials (Figure 3). The roughness of the platform of the physic model can be assumed to be similar to the roughness of concrete pipes in sewer systems.
- Tests were conducted using different types of shoes including waterproof boots normally used during sewer inspection. It should guarantee a similar friction between the bottom of the platform and the subjects. During the tests, the conditions experienced during inspections were maintained, where friction is experimented between the bottom of the pipe and the workers.
- Tests were conducted considering different visibility conditions. Particularly, glasses were used to decrease visibility during some tests in order to take into account the possibility that pedestrians do not have high visibility conditions during flooding events (i.e., floods event occurring at night, people with wetted and fogged glasses, etc.). This aspect could be relevant due to the absence of natural lighting in sewer networks.
- Last but not least, the flow parameters achieved during the tests carried out by Russo et al. [8] and Martínez et al. [9] were characterized by low flow depths and high flow velocity. These conditions are typical in urban flooded areas where the surface presents a low roughness and they fit quite well with respect to the flow conditions in sewers where a low flow rate is normally observed in the gutter or where circular and ovoid pipes flow with high velocity to avoid sedimentation problems.
2.3. Wastewater Flow Model
2.4. Model Scenarios
- (a)
- Maximum flow—This scenario corresponds to the daily peak flow that according to the daily pattern shown in Figure 5 is 1.40 times the daily average flow.
- (b)
- Average flow—This scenario corresponds to the mean daily flow.
- (c)
- Minimum flow—This scenario corresponds to the daily minimum flow that according to the daily pattern shown in Figure 5 is 0.56 times the daily average flow.
- Four v∙D product criteria (0.22, 0.4, 0.5, and 0.6 m2/s)
- Two water depth D criteria (0.5 and 1 m).
3. Results
Hazard Assessment
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Acknowledgments
Conflicts of Interest
References
- Haurum, J.B.; Bahnsen, C.H.; Pedersen, M.; Moeslund, T.B. Water level estimation in sewer pipes using deep convolutional neural networks. Water 2020, 12, 3412. [Google Scholar] [CrossRef]
- Tscheikner-Gratl, F.; Caradot, N.; Cherqui, F.; Leitão, J.P.; Ahmadi, M.; Langeveld, J.G.; Le Gat, Y.; Scholten, L.; Roghani, B.; Rodríguez, J.P.; et al. Sewer asset management–state of the art and research needs. Urban Water J. 2019, 16, 662–675. [Google Scholar] [CrossRef] [Green Version]
- Lee, J.; Park, C.; Baek, S.; Han, S.; Yun, S. Risk-based prioritization of sewer pipe inspection from infrastructure asset management perspective. Sustainability 2021, 13, 7213. [Google Scholar]
- Hansen, B.D.; Rasmussen, S.H.; Uggerby, M.; Moeslund, T.B.; Jensen, D.G. Comprehensive feature analysis for sewer deterioration modeling. Water 2021, 13, 819. [Google Scholar] [CrossRef]
- Abt, S.R.; Wittler, R.J.; Taylor, A.; Love, D.J. Human stability in a high flood hazard. Water Resour. Bull. 1989, 25, 881–890. [Google Scholar] [CrossRef]
- Shand, T.; Cox, R.J.; Smith, J.; Blacka, M. Appropriate criteria for the safety and stability of people in stormwater design. In Proceedings of the National Conference of the Stormwater Industry Association, Sydney, Australia, 8–12 November 2010; pp. 1–12. [Google Scholar]
- Russo, B.; Gómez, M.; Macchione, F. Pedestrian hazard criteria for flooded urban areas. Nat. Hazards 2013, 69, 251–265. [Google Scholar] [CrossRef]
- Martínez-Gomariz, E.; Gómez, M.; Russo, B. Experimental study of the stability of pedestrians exposed to urban pluvial flooding. Nat. Hazards 2016, 82, 1259–1278. [Google Scholar] [CrossRef] [Green Version]
- Deccan Herald. 2019 Records Highest Deaths while Cleaning Sewer in Last 5 Years. 2019. Available online: https://www.deccanherald.com/national/2019-records-highest-deaths-while-cleaning-sewer-in-last-5-years-807401.html (accessed on 15 October 2021).
- Centro de Estudios y Experimentación de Obras Públicas (CEDEX). Guía Técnica Sobre Redes de Saneamiento y Drenaje Urbano; Ministerio de Fomento, Ed.; Gobierno de España: Madrid, Spain, 2009; ISBN 978-84-7790-491-5. [Google Scholar]
- Clavegueram de Barcelona S.A. (CLABSA). Pla Especial de Clavegueram de Barcelona (PECLAB ’97) [(Barcelona Drainage Master Plan, 1997)]; CLABSA: Barcelona, Spain, 1997. [Google Scholar]
- Canal de Isabel II. Normas Para Redes de Saneamiento. 2020. Available online: https://www.canaldeisabelsegunda.es/documents/20143/79037/2016_Normas_Redes_Saneamiento.pdf/e1461e6b-3e64-8356-2b8f-05ee9845c4d8 (accessed on 15 October 2021).
- Escuela del Agua (SUEZ Spain). Limpieza Avanzada de la Red de Drenaje, 2nd ed.; MOOC (Massive Open Online Course); 2021; Available online: https://miriadax.net/web/limpieza-avanzada-de-la-red-de-drenaje-2-edicion-/inicio (accessed on 15 October 2021).
- Dirección de Obras Hidráulicas. Manual de Drenaje Urbano; Ministerio de Obras Públicas, Ed.; Gobierno de Chile: Santiago, Chile, 2013.
- Locatelli, L.; Russo, B.; Acero Oliete, A.; Carlos Sánchez Catalán, J.; Martínez-Gomariz, E.; Martínez, M. Modeling of E. coli distribution for hazard assessment of bathing waters affected by combined sewer overflows. Nat. Hazards Earth Syst. Sci. 2020, 20, 1219–1232. [Google Scholar] [CrossRef]
- Federal Emergency Management Agency (FEMA). The Floodway: A Guide for Community Permit Officials; FEMA: Washington, DC, USA, 1979.
- Martínez-Gomariz, E.; Locatelli, L.; Guerrero, M.; Russo, B.; Martínez, M. Socio-economic potential impacts due to urban pluvial floods in Badalona (Spain) in a context of climate change. Water 2019, 11, 2658. [Google Scholar] [CrossRef] [Green Version]
- Clark County Regional Flood Control District (CCRFCD). Hydrological Criteria and Drainage Design Manual; Clark County Regional Flood Control District: Las Vegas, NV, USA, 1999. [Google Scholar]
- Locatelli, L.; Guerrero, M.; Russo, B.; Martí nez-Gomariz, E.; Sunyer, D.; Martí nez, M. Socio-economic assessment of green infrastructure for climate change adaptation in the context of urban drainage planning. Sustainability 2020, 12, 3792. [Google Scholar] [CrossRef]
Year | Spain 1 | USA 2 | UE 3 |
---|---|---|---|
2019 | 2 | 8 | NA |
2018 | NA | NA | 0 |
Kilometres of Visitable Conduits with High Hazard | |||||
---|---|---|---|---|---|
v∙D (m2/s) | |||||
Scenario | Depth Criteria | 0.22 | 0.4 | 0.5 | 0.6 |
Max | D > 1 m | 2778 | 961 | 422 | 312 |
D > 0.5 m | 3099 | 1572 | 1247 | 1138 | |
Mean | D > 1 m | 2319 | 327 | 312 | 312 |
D > 0.5 m | 2597 | 798 | 783 | 783 | |
Min | D > 1 m | 619 | 312 | 312 | 312 |
D > 0.5 m | 883 | 613 | 613 | 613 |
Percentage of Visitable Conduits with High Hazard with Respect to the Total Visitable Ones | |||||
---|---|---|---|---|---|
v∙D (m2/s) | |||||
Scenario | Depth Criteria | 0.22 | 0.4 | 0.5 | 0.6 |
Max | D > 1 m | 6.7% | 2.3% | 1.0% | 0.8% |
D > 0.5 m | 7.5% | 3.8% | 3.0% | 2.7% | |
Mean | D > 1 m | 5.6% | 0.8% | 0.8% | 0.8% |
D > 0.5 m | 6.2% | 1.9% | 1.9% | 1.9% | |
Min | D > 1 m | 1.5% | 0.8% | 0.8% | 0.8% |
D > 0.5 m | 2.1% | 1.5% | 1.5% | 1.5% |
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Russo, B.; Locatelli, L.; Yubero, D.; Ruiz, O.; Oliete, A.A. Assessment of Human Stability in Sewer Systems during Dry Weather Conditions. Water 2021, 13, 2954. https://doi.org/10.3390/w13212954
Russo B, Locatelli L, Yubero D, Ruiz O, Oliete AA. Assessment of Human Stability in Sewer Systems during Dry Weather Conditions. Water. 2021; 13(21):2954. https://doi.org/10.3390/w13212954
Chicago/Turabian StyleRusso, Beniamino, Luca Locatelli, Daniel Yubero, Oscar Ruiz, and Alejandro Acero Oliete. 2021. "Assessment of Human Stability in Sewer Systems during Dry Weather Conditions" Water 13, no. 21: 2954. https://doi.org/10.3390/w13212954
APA StyleRusso, B., Locatelli, L., Yubero, D., Ruiz, O., & Oliete, A. A. (2021). Assessment of Human Stability in Sewer Systems during Dry Weather Conditions. Water, 13(21), 2954. https://doi.org/10.3390/w13212954