Storm Drainage Research Articles

Is increased flooding in Bangkok a result of rising local temperatures?

The recent increase in the frequency of urban flooding in Bangkok has led to speculation that global warming may be to blame. Assessing this, however, is challenging, as Bangkok represents an ever-changing environment with changing storm drainage infrastructure, limited flood and precipitation data, and a tropical setting that complicates the relationship precipitation extremes exhibit with temperature. This study attempts to create a framework to investigate the merits of the above speculation, using ground observations of precipitation maxima, flood inundation, and dew point temperature, along with simulations from General Circulation Models (GCMs) to present multiple lines of evidence to compensate for the weaknesses any individual evidence may have. The complexity of flooding in an urban stormwater drainage network is accounted by focussing instead on flood inundation information conditional to the incident dew point temperature which is increasing as a result of warming. The assessment identifies a markedly different pattern of change in the east versus the west of the city, attributing this to population change in the two parts, further complicating the link to global warming. Application of the developed methodology using the most recent GCM simulations available suggests the increase in flooding is a pattern that can be expected to continue.

SUSTAINABLE URBAN PUBLIC PARK LANDSCAPE DESIGN CRITERIA BASED ON COMMUNITY PERCEPTION AND ASPIRATIONS

This article interprets the perception and aspirations of the city community, as a cornerstone of drafting the design criteria of a community-based city park landscape, which is effective and sustainable. Flooding and drought problems in Jakarta and surrounding areas should be resolved in a comprehensive, integrated and sustainable manner. Referring to the Water Sensitive Urban Design (WSUD) which is an innovation in integrated water management, it is recommended to develop the function of detention and retention ponds as part of storm drainage system, replacing conventional system. Development of the city park landscape criteria as the synergies of the RTH function and the detention/retention ponds should be approached in a very careful, avoiding fatal malfunction and harsh rejection of the user community. The best approach should be done through tracing the needs, desires and expectations of the city community as the ‘end user' as well as 'super client' of the city park. Research on the perception and aspirations of the city community on the idea of the development of City Park with the role of retention/retention ponds has been conducted between February to May 2020 in Jabodetabek.

The role of storm movement in controlling flash flood response: an analysis of the 28 September 2012 extreme event in Murcia, southeastern Spain

AbstractFlash flooding is strongly modulated by the spatial and temporal variability in heavy precipitation. Storm motion prompts a continuous change of rainfall space-time variability that interacts with the drainage river system, thus influencing the flood response. The impact of storm motion on hydrological response is assessed for the 28 September 2012 flash flood over the semi-arid and medium-sized Guadalentín catchment in Murcia, southeastern Spain. The influence of storm kinematics on flood response is examined through the concept of ‘catchment-scale storm velocity’. This variable quantifies the interaction between the storm system motion and the river drainage network, assessing its influence on the hydrograph peak. By comparing two hydrological simulations forced by rainfall scenarios of distinct spatial and temporal variability, the role of storm system movement on the flood response is effectively isolated. This case study is the first to: (i) show through the catchment-scale storm velocity how storm motion may strongly affect flood peak and timing; and (ii) assess the influence of storm kinematics on hydrological response at different basin scales. In the end, this extreme flash flooding provides a valuable case study of how the interaction between storm motion and drainage properties modulate hydrological response.

Spatio-temporal variability monitoring of the floods in the center-west of the Buenos Aires Province (Argentina) using remote sensing techniques

Floods are recurring events in Buenos Aires Province, mainly caused by high-intensity precipitation, and in some cases, they persist for long periods. The objective of this study is to analyze how the topography of the central-western portion of Buenos Aires Province determines the occurrence and the extent of floods. The presence of shallow lakes characterizes the area which is controlled by the topography. LANDSAT 5 and 8 images corresponding to periods of drought and flooding in the area were compared with topographic profiles and digital elevation models generated from SRTM 3 arc/sec data. The results showed that in those areas where there are aligned dunes, and after significant storm drain engineering works, during the wet periods, the lakes, their overflows, and the subsequent runoff to the east of Buenos Aires Province flow freely, limiting the flood areas. Due to this topography, the lakes became a more permanent feature of the landscape, even during extreme drought events. In contrast, in those areas where parabolic dunes predominate, the landscape is more affected by droughts and floods. During drought events, we observed a small number of shallow lakes, and during strong storms with high-intensity rainfall, the number of lakes increases and large flooded areas generate damage to agricultural fields and neighboring cities, either due to natural causes or improvised and illegal storm drains. Early warning of flood risks and a systematic territorial ordaining would be the key to the management of the area.

Qualification Of Vacant Urban Lands As Potential Green Spaces Used ForOptimising The Storm Drainage System Of Resistencia City (Argentina)

The increasing rainfall issues related with current humid periods, as part of city of Resistencia’s climate in Argentina, impact and affect their population. This city has an inefficient storm drainage system, as a result of human intervention in the natural environment. Moreover, there is a wide range of vacant land that can offer and integrated green open spaces system that could relief and absorb the overflow of rainfall, while ensuring optimum solutions to face floods with less intervention, less environmental impact and low investment. The outcomes of this research have pointed out four key sectors suffering frequent flood and could be relief with green open spaces. This vacant land, are still available to be incorporated as absorbent areas that could also be design a flooding park, offering not only absorbent areas but also could be useful for leisure purposes, available for the community.

Sensitivity analysis of permeable pavement hydrological modelling in the Storm Water Management Model

The Storm Water Management Model (SWMM), widely used by engineers to design or analyse stormwater networks, allows to model the so-called Low Impact Development (LID) controls, which reduce the flow conveyed to traditional networks. But, values for LID control parameters are often unknown. Furthermore, it is not always easy to link the cross-section materials to those provided by the model, particularly in the soil layer. This article provides a global sensitivity analysis for the PP type of LID control, in order to support practitioners in calibration tasks. The analysis explores what factors are the most influential and which can be fixed while calibrating a model. In particular, flow volume and peak are studied but the analysis also explores the influence of storm length and drain layer, which is optional. At the end, the most influential parameters, and those that can be neglected are presented, showing that we can focus on quite less parameters than initially given when calibrating a PP model in SWMM.

Sources of Low Level Human Fecal Markers in Recreational Waters of Two Santa Barbara, CA Beaches: Roles of WWTP Outfalls and Swimmers

Worldwide, fecal indicator bacteria (FIB) evidence coastal water contamination for which sources are unknown. Here, for two FIB-impacted Santa Barbara recreational beaches, hypothesized fecal sources were investigated over three dry seasons (summers) using nearly 2000 field samples of water (ocean, creek, groundwater), sand, sediments, effluent and fecal sources. In years 1 and 2, gull and dog feces were identified as the probable main FIB sources to surf zone waters, yet HF183 human fecal markers were consistently detected. Determining HF183 sources was therefore prioritized, via year 3 sub-studies. In lower watersheds, human and dog wastes were mobilized by small storms into creeks, but no storm drain outfalls or creeks discharged into surf zones. Beach area bathrooms, sewers, and a septic system were not sources: dye tracing discounted hydraulic connections, and shallow groundwater was uncontaminated. Sediments from coastal creeks and downstream scour ponds, nearshore marine sediments, and sands from inter- and supratidal zones contained neither HF183 nor pathogens. Two nearby wastewater treatment plant (WWTP) outfalls discharged HF183 into plumes that were either deep or distant with uncertain onshore transport. Regardless, local sources were evidenced, as surf zone HF183 detection rates mostly exceeded those offshore and nearshore (around boat anchorages). The presence of swimmers was associated with surf zone HF183, as swimmer counts (on weekdays, holidays, weekends, and during races) significantly correlated (p<0.05, n = 196) to HF183 detections. Besides comprehensively assessing all possible fecal sources, this study provides new explanations of chronic low-level human markers in recreational beach surf zones, suggesting likely lowest achievable HF183 thresholds.

Quantitative source apportionment of dissolved organic matters in wet weather overflows of storm drainage systems based on degradation potential index and end member mixing model

Dissolved organic matter (DOM) in wet weather overflows (WWFs) of storm drainage systems mainly originates from anthropogenic sources, such as paved runoff, illegally discharged domestic sewage and the retained sediment. This study provides a promising method to quantitatively apportion the WWF DOM of storm drainage systems using degradation potential index (DPI) and end member mixing (EMM) model. DPI is derived from excitation-emission matrix parallel factor analysis (EEM-PARAFAC), which can endow the end members and itself of WWF DOM with numerical features, and thus help quantify the source contributions of WWF DOM in EMM model. Findings show that (1) DPI was a reliable tool in the quantitative source apportionment of WWF DOM, owing to its features of small variance within source and large variances between sources; (2) DPI combined with EMM model could help identify the factors that induce significant impacts on the source contributions of WWF DOM, such as the storm pumping discharge and antecedent dry days in our case study; (3) the identified factors could guide the development of effective strategies for WWF DOM control, e.g. sediment management in our case.

Impact of underground storm drain systems on larval ecology of Culex and Aedes species in urban environments of Southern California

An extensive network of storm water conveyance systems in urban areas, often referred to as the “underground storm drain system” (USDS), serves as significant production habitats for mosquitoes. Knowledge of whether USDS habitats are suitable for newly introduced dengue vectors Aedes aegypti and Ae. albopictus will help guide surveillance and control efforts. To determine whether the USDS functions as a suitable larval habitat for Culex, Ae. aegypti and Ae. albopictus in southern California, we examined mosquito habitat utilization and larval survivorship using laboratory microcosm studies. The data showed that USDS constituted 4.1% of sampled larval habitats for Ae. aegypti and Ae. albopictus, and 22.0% for Cx. quinquefasciatus. Furthermore, USDS water collected in the summer completely inhibited Aedes larval development, but yielded a 15.0% pupation rate for Cx. quinquefasciatus. Food supplementation in the microcosms suggests that nutrient deficiency, toxins and other factors in the USDS water led to low success or complete failure of larval development. These results suggest that USDS habitats are currently not major productive larval habitats for Aedes mosquitoes in southern California. Our findings prompt inclusion of assessments of pupal productivity in USDS habitats and adult mosquito resting sites in the mosquito surveillance program.

Characterization of Stormwater Runoff Based on Microbial Source Tracking Methods.

Rainfall and associated urban runoff have been linked to an increased deterioration of environmental waters, carrying several pollutants including pathogenic microorganisms. Such happens because fecal matter is washed into storm drainage pipes that are afterward released into environmental waters. Stormwater has not been extensively characterized as it is, because most studies are performed either on drainage pipes that are often impacted by sewage leakage or directly in environmental waters following a rain event. In this study, stormwater collected directly from the streets, was monitored for the presence of fecal indicator bacteria (FIB) and three potential important sources of fecal contamination in urban environments (human, cats, and dogs) in three distinct basins in Lisbon, Portugal. Stormwater was collected in sterilized plastic boxes inserted in the storm drains, therefore collecting only runoff. High concentration of fecal contamination was detected with a high percentage of the samples displayed at least one source of contamination. A strong relationship was found between the number of detected sources and the precipitation levels. Although no statistical correlation was found between the locations and the presence of FIB or source markers, the results show a trend in geographical information on the type of urban use in each basin. To the best of our knowledge, this is the first study analyzing the runoff collected directly from the streets. This study suggests that, in urban areas, stormwater runoff is highly impacted by fecal matter, not only from domestic animals but also from human origin, before any cross-contamination in the drainage system and may, by itself, pose a high risk to human health and the environment, particularly if water reuse of this water without further disinfection treatment is the final goal.

Spotting strategic storm drain inlets in flat urban catchments

Storm drain inlet blockage causes more flooding incidents than does storm sewer overloading in flat urban catchments. Although inlet clearance has proved to be cost-effective in mitigating pluvial flooding, clearing all inlets in the wet season is unfeasible. No study has sought to partition the role of storm drain inlets because the dynamic flow exchange at every inlet is impossible to monitor at a catchment scale and even hard to calculate. This study presents a proactive approach to identifying strategic (i.e., most influential) inlets to save considerable labor costs in grate inlet maintenance. Our findings show that the tapered Pareto distribution can describe the distribution of inlet interception rates almost invariant to rainfall types. A modified Pareto principle called the 70–25 rule is derived, suggesting that 70% surface runoff is drained by the top 25% inlets. A nested hydrodynamic model, which solves full shallow water equations and captures detailed physical processes, was built to compute surface runoff intercepted by grate inlets in the built environment. The model is composed of a subcatchment scale, 2D-1D dual drainage model embedded in a catchment scale 1D model. The 2D-1D interaction was described by a piecewise function of piezometric head at the grate inlet; the parameters in each subfunction were statistically derived from a series of 3D numerical experiments involving full processes from free-surface flow to pressurized flow. The 2D model was built on a sensitivity-tested, unstructured mesh with allowable triangle areas ranging from 0.15 to 6 m2. The simulations showed a mild (ca.5%) versus radical (40–50%) reduction in runoff interception with the removal of the non-strategic versus strategic inlets under non-extreme rainfalls. The application to the low-lying, ultra-urban test case confirmed the robustness and effectiveness of the method for strategic inlets identification.

Improving Indian meteorological department method for 24- hourly rainfall downscaling to shorter durations for IDF modelling

The development of Intensity-Duration-Frequency (IDF) models for storm drain design and related flood mitigation structures requires rainfall amount and corresponding duration records. To achieve this purpose, three short duration downscaling methods from 24-hourly rainfall amount data were selected for improvement, namely: IMD, AIMD and MCIMD, with the CAMS method used as the experiment control. Three types of general PDF-IDF models (GEVT-1, LPT-3 and ND) were developed based on the downscaling methods yielding goodness of fit (R2) with very high correlation of 0.995–0.999 and model accuracy with mean square error (MSE) of 4.123–7.85. The PDF-IDF models predicted intensities plotted against durations for different return periods of 2, 5, 10, 25, 50 and 100 years, showed visual differences in the predictive performance of the intensities derived from the downscaling methods. Kruskal-Wallis non-parametric test of significance at 5% level carried out showed that no-significant difference exist for 15-60 minutes duration, while the difference was significant for durations between 90–300 minutes. The LPT-3 based on MCIMD yielded higher improved performance in prediction of intensities relative to the IMD. The level of improvement ranges from 35.17 to 52.26% and 25.0 to 39.89%; while that of AIMD ranges from 10.97 to 20.87% and 3.33 to 12.53% for 10 and 100 year return periods, respectively. The use of the IMD downscaling method with the LPT-3 PDF-IDF model for design purposes will be justified if modified with some percentage improvement or adjustment factor.

Hydraulic shortcuts increase the connectivity of arable land areas to surface waters

Abstract. Surface runoff represents a major pathway for pesticide transport from agricultural areas to surface waters. The influence of artificial structures (e.g. roads, hedges, and ditches) on surface runoff connectivity has been shown in various studies. In Switzerland, so-called hydraulic shortcuts (e.g. inlet and maintenance shafts of road or field storm drainage systems) have been shown to influence surface runoff connectivity and related pesticide transport. Their occurrence and their influence on surface runoff and pesticide connectivity have, however, not been studied systematically. To address that deficit, we randomly selected 20 study areas (average size of 3.5 km2) throughout the Swiss plateau, representing arable cropping systems. We assessed shortcut occurrence in these study areas using three mapping methods, namely field mapping, drainage plans, and high-resolution aerial images. Surface runoff connectivity in the study areas was analysed using a 2×2 m digital elevation model and a multiple-flow algorithm. Parameter uncertainty affecting this analysis was addressed by a Monte Carlo simulation. With our approach, agricultural areas were divided into areas that are either directly, indirectly (i.e. via hydraulic shortcuts), or not at all connected to surface waters. Finally, the results of this connectivity analysis were scaled up to the national level, using a regression model based on topographic descriptors, and were then compared to an existing national connectivity model. Inlet shafts of the road storm drainage system were identified as the main shortcuts. On average, we found 0.84 inlet shafts and a total of 2.0 shafts per hectare of agricultural land. In the study catchments, between 43 % and 74 % of the agricultural area is connected to surface waters via hydraulic shortcuts. On the national level, this fraction is similar and lies between 47 % and 60 %. Considering our empirical observations led to shifts in estimated fractions of connected areas compared to the previous connectivity model. The differences were most pronounced in flat areas of river valleys. These numbers suggest that transport through hydraulic shortcuts is an important pesticide flow path in a landscape where many engineered structures exist to drain excess water from fields and roads. However, this transport process is currently not considered in Swiss pesticide legislation and authorization. Therefore, current regulations may fall short in addressing the full extent of the pesticide problem. However, independent measurements of water flow and pesticide transport to quantify the contribution of shortcuts and validating the model results are lacking. Overall, the findings highlight the relevance of better understanding the connectivity between fields and receiving waters and the underlying factors and physical structures in the landscape.

Investigation on the content of petroleum products in the surface run-off from the road pavements

Road transport is considered to be one of the leaders from the viewpoint of damage caused to the environment. One of the principal problems, which specialists encounter with in connection with exploitation of automobiles, is the discharge of highly contaminated surface wastewaters from highways onto the close ground territories and into the close water reservoirs. The objective of the present investigation presumed determination of the real content of oil products in the surface run-off waters from the surfaces of automobile roads. Within the frames of the present investigation, we studied the available experience in assessment of the content of pollutants in storm drain from the objects of transport infrastructure. The content of petroleum products in surface waste waters formed on highways was studied.

Experimental Study on the Inlet Discharge Capacity under Different Clogging Conditions

Storm drainage inlets transport urban runoff and discharge to underground sewer systems. If the inlet structure is blocked, the urban drainage system is hampered, leading to urban flooding. To quantitatively analyze the influence of clogging conditions on inlet discharge capacity, laboratory experiments were conducted to address the impact of different inlet clogging conditions on inlet discharge capacity under different upstream discharge conditions. These were based on a two-layer platform that mimicked a complete inlet structure including a drainage grate, a rainwater well, and a connecting pipe. The results show that the water flow near the inlet was similar to weir flow when the rainwater well was not full, whereas the water flow state near the inlet behaved similarly to orifice flow after becoming full. In addition, it was found that the clogging extent and position can significantly influence the comprehensive discharge capacity of the street inlet. The experimental dataset was used to calculate the inlet discharge coefficients of the weir and orifice flow states under different clogging conditions. The results are applicable to research addressing the formation mechanisms of urban floods. Additionally, this study is of practical significance for early warning systems and emergency response support during heavy rainfall.

К вопросу экологического состояния ливневых сточных вод на урбанизированной территории

The article raises the issue of the ecological state of storm wastewater, their technical condition. The issues of assessing the functioning of storm sewers are included in the list of municipal environmental control, which is carried out by the executive authorities in the field of ecology and nature management. The research paper outlines the key problems associated with underfunding of the current work to ensure the efficient operation of storm water. The main categories in the system “treatment facilities – storm drains – collectors” are considered. The traditional stormwater runoff system involves the diversion of surface runoff through open water bodies (e.g. river systems). The main environmental indicators to be achieved during the construction and commissioning of a complex of sewage storm treatment facilities have been analyzed. The analysis of the design indicators showed that a total of 18.9 million m3 of storm water, rainwater runoff and drainage waters are subject to treatment. The measures for the installation of sewage treatment plants, storm sewers will prevent the river Volga from entering of more than 22 thousand tons of suspended solids, including heavy metals and 1.2 thousand tons of oil products. According to the project documentation, the construction of more than 50 facilities will allow upgrading the stormwater drainage system of the city of Volgograd within the framework of the National Project “Ecology”. The conclusions reflected in the article reveal the main reasons for the current situation: inconsistency of repair and restoration work to replace parts, assemblies; insufficient amount of technical re-equipment; inconsistency of the chemical composition of wastewater with the established regulatory environmental indicators; insufficient municipal control of the services responsible for this object; insufficient financial support.

Sea‐level rise drives wastewater leakage to coastal waters and storm drains

AbstractSea‐level rise (SLR) is expected to compromise coastal wastewater infrastructure (WIS) via groundwater inundation (GWI). We conducted a field‐based study in urban Honolulu, Hawai'i using spring tides as a proxy for future sea levels to quantify the hydrologic connection of WIS. This study focused on two possible pathways: (1) direct GWI of WIS and subsequent discharge into the coastal ocean and (2) indirect inundation of WIS evidenced in storm drains. We used geochemical tracers and emerging organic contaminants (EOCs) to monitor groundwater discharge and its wastewater content. Groundwater discharge and EOCs fluctuated with tides for coastal and canal groundwater and surface water samples, and storm drains, indicating tidally driven GWI and wastewater discharge. This study presents some of the first field‐based evidence for GWI of coastal WIS and demonstrates that SLR is creating additional risks to environmental and human health.

Parameter optimization and uncertainty assessment for rainfall frequency modeling using an adaptive Metropolis-Hastings algorithm.

A new parameter optimization and uncertainty assessment procedure using the Bayesian inference with an adaptive Metropolis-Hastings (AM-H) algorithm is presented for extreme rainfall frequency modeling. An efficient Markov chain Monte Carlo sampler is adopted to explore the posterior distribution of parameters and calculate their uncertainty intervals associated with the magnitude of estimated rainfall depth quantiles. Also, the efficiency of AM-H and conventional maximum likelihood estimation (MLE) in parameter estimation and uncertainty quantification are compared. And the procedure was implemented and discussed for the case of Chaohu city, China. Results of our work reveal that: (i) the adaptive Bayesian method, especially for return level associated to large return period, shows better estimated effect when compared with MLE; it should be noted that the implementation of MLE often produces overy optimistic results in the case of Chaohu city; (ii) AM-H algorithm is more reliable than MLE in terms of uncertainty quantification, and yields relatively narrow credible intervals for the quantile estimates to be instrumental in risk assessment of urban storm drainage planning.

Assessing the Feasibility of a Cloud-Based, Spatially Distributed Modeling Approach for Tracking Green Stormwater Infrastructure Runoff Reductions

Use of green stormwater infrastructure (GSI) to mitigate urban runoff impacts has grown substantially in recent decades, but municipalities often lack an integrated approach to prioritize areas for implementation, demonstrate compelling evidence of catchment-scale improvements, and communicate stormwater program effectiveness. We present a method for quantifying runoff reduction benefits associated with distributed GSI that is designed to align with the spatial scale of information required by urban stormwater implementation. The model was driven by a probabilistic representation of rainfall events to estimate annual runoff and reductions associated with distributed GSI for various design storm levels. Raster-based calculations provide estimates on a 30-m grid, preserving unique combinations of drainage factors that drive runoff production, hydrologic storage, and infiltration benefits of GSI. The model showed strong correspondence with aggregated continuous runoff data from a set of urbanized catchments in Salinas, California, USA, over a three-year monitoring period and output sensitivity to the storm drain network inputs. Because the model runs through a web browser and the parameterization is based on readily available spatial data, it is suitable for nonmodeling experts to rapidly update GSI features, compare alternative implementation scenarios, track progress toward urban runoff reduction goals, and demonstrate regulatory compliance.

Design, analysis and data management of open Drain/Sewer solid waste cleaning robot

Sewage Treatment Plants are designed to handle the volume of sewage produced by target areas, however we face issues in streamlining the city’s sewage lines to its destination on the grid. It is advisable to treat sewage at source and localize the STP plants. Indian city planning does not have the means and methods to complete elaborate systems at a stretch, this has caused disparity in development even within cities which has left it with numerous open drains and sewers. Though laid to serve as storm drains, open drains and sewers found across taluks are being used as sewage disposal lines. To overcome the difficulty of maintaining such structures, an automated open drain/sewer solid waste desilting machine is proposed. The machine removes all the solid waste that disrupts the steady flow of sewage. As a result, the natural flow velocity with which the pipelines are laid carries over such waste to the required STP. The machine is attached with ultrasonic sensors that detect the amount of waste present and its range. This data is transferred using an IoT software and the resulting data is a coherent graph.