World Environmental and Water Resources Congress 2020: Emerging and Innovative Technologies and International Perspectives

Water system managers increasingly operate in distributed information exchange environments characterized by internal and external data communications. These sensor-controller-machine intensive environments must communicate internally (within and between device-level rings, within and between subsystems, and/or within and between systems) and externally (with and between original equipment manufacturers and/or with and between credentialed third parties). In critical infrastructure, cyber risk is magnified due to the heterogeneous nature of the technologies, protocols, and standards. Such an environment requires an approach that goes beyond information technology practices incorporating the unique needs of operational technologies. Protecting blended topologies requires a multi-dimensional framework integrating logical segmentation, cyber hygiene, network oversight, and human reliability. Logical segmentation compartmentalizes the network to align with service delivery. Cyber hygiene provides intrusion detection/prevention, identity services, malware protection, and network behavior analysis. Network oversight monitors network activity detecting and automatically responding to non-compliant actions with response policies that are service delivery fail-safe cognizant. Human reliability recognizes the potential for inadvertent and/or purposeful harmful actions and places digital safeguards at critical points to avoid compromise. Each dimension is significant itself but, collectively, they dramatically reduce the potential for gap and blind-zone formation with technologies and practices that are deployed in industrial and control system network operations today. This paper summarizes recent cyber-physical threat events and describes best practices in use across small and large critical infrastructure enterprises. Findings highlight the role network architecture design and operational practices to reduce attack surfaces and, at the same time, increase operational efficiency, ensure data integrity, and provide operational resilience in the face of evolving threats to cyber-physical systems.

Remote operation of gates is desirable for multiple purposes. For instance, in the case of flood control, the storage ponds (e.g., detention ponds, reservoirs, wetlands) are often located in remote areas. For draining storage ponds by gravity, siphons, and/or sloped pipes could be used. For shallow ponds (up to 6 meters of storage height), siphons and sloped pipes could be used while, as for deeper ponds, only sloped pipes could be used. Siphons only require anchoring, whereas sloped pipes would require a trench on the storage berm. This paper presents a low-cost hardware system for remote water release, which could be used for multiple purposes. In the case of flood control, remote operation could be used to release water hours or days before heavy rainfall events to increase the capacity of storage units (e.g., wetlands, reservoirs, detention ponds). The proposed system consists of a modular and integrated hardware/software platform that interfaces automated gates for siphons and sloped pipes, sensors, and communication for remote operation using a 3G/4G cellular network. The proposed system is powered using a battery, which is recharged by a solar panel. Multiple prototypes of the system (single and array) were built and extensively tested in our laboratory. This approach could open the doors for low-cost applications of remotely-operated water release to areas such as flood control, management of water levels in wetlands for ecological purposes, among others.

Submerged oscillating water columns (SOWC) are a type of hydraulic structures commonly classified as wave energy converters (WEC) that can extract energy from ocean surface waves in intermediate water depths. This study explores the effect of reducing the entrance loss and improving energy efficiency by modifying the SOWC opening. A basic SOWC device consists of two submerged cylinders with openings at the bottom that allow the flow to move in and out. A connecting pipe allows entrapped air to flow between the cylinders as waves pass. Ideally, cylinders are spaced at half a wavelength apart to maximize the height differential. A series of experimental tests have been carried out at Idaho State University’s Water Resources Lab to explore the validity of the concept. Numerical simulations using computational fluid dynamics (CFD) were completed and the efficiency of the SOWCs obtained. The results of 32 simulations using Stokes Cnoidal waves have been investigated for different wave configurations and SOWC cylinder openings. The effect of four parameters including the opening percentage and shape, water depth, wave height, and wave length were investigated. The numerical CFD modeling indicated that the entrance conditions and shape can affect the water elevation movement inside the chambers. Optimum openings can increase the efficiency by up to 15%.

Flood is one of the most disastrous natural calamities which results in loss of human lives coupled with significant economic and infrastructural losses. Climate change and anthropogenic activities result in increased flood frequency and magnitude. This paper discusses an exclusive way of flood mitigation by utilizing and integrating structural and nonstructural approaches. Effective usage of storage systems (wetlands, detention ponds, and reservoirs) by operating in a coordinated manner plays a vital role for the same objective. For this purpose, a low-cost, green, and smart system have been designed by integrating hardware and software components. A framework has been developed to control siphon, gates, pumps, water level sensors, and air-vents, and perform a remote operation using a 3G/4G cellular connection. A prototype has been designed and tested multiple times in the field. To check the reliability and robustness of the system, structural analysis has been performed using a finite element software by applying suitable wind load. This load includes hurricane-force winds as the primary purpose of this system is to mitigate floods due to extreme rainfall and storm surge caused by hurricanes. The structural response of the siphon system against these high-intensity winds is also analyzed, laying the groundwork for future wind structure interaction analysis.

This study investigates the use of digital cameras for remote sensing of suspended sediment concentration (SSC) in streams. The performance of the digital cameras in estimating SSC is assessed, and the effect of sediment color on the accuracy of this method is investigated, based upon laboratory experiments employing sediments of different colors. The results of this study indicate that: 1) red waveband reflectance values of the digital images indicates a strong positive linear relationship with the SSC within the range of 25–200 mg/l, while green and blue wavebands seem to be insensitive to the SSC variations; and 2) sediment color influences the reflectance properties of the water surface, resulting in higher reflectance of lighter color sediments than darker colored sediments. The correlation between the SSC and calculated reflectance values demonstrates that this method is suitable for mapping the SSC in complex river settings with a wide range of suspended sediment conditions.

Lower Indus Basin provides water supply to 80% of irrigated agriculture in the province of Sindh in Pakistan. After the Indus Water Treaty between India and Pakistan in 1960, massive infrastructure, as “Indus Basin Replacement Works” were constructed to divert the waters of River Indus and Kabul River to Jhelum-Chenab and eastern rivers. The waters of Indus, Jhelum, and Chenab Rivers were distributed within the four provinces of Pakistan through a water apportionment accord in 1991. The Indus Waters Treaty and Water Apportionment Accord do not provide exclusive share of water for Indus Delta to maintain its ecological integrity. Current flows reaching delta are below the environmental flow requirement thus causing degradation of Indus Delta. Moreover, sediment supply to delta has decreased due to river storage and control structures upstream and it is below the level needed to maintain the delta with respect to local mean sea level. Water availability, demand, and apportionment data was collected and analyzed to better understand water balance and environmental flows in the basin. This work builds on previous work done with flow data from 1920 to 2003 and presented in the report of “Technical Committee on Water Resources 2005”. Flow, storage, and apportionment data at multiple locations throughout the Indus Basin was analyzed for 1998 to 2018. Results indicate that the water resources in Indus Basin are already over-committed, thus causing water scarcity and frequent water crisis. Results show a need for better management of both sediments and environmental flows. Results also indicate mistrust among different provinces regarding water apportionment. Based on water balance and shortage of environmental flows it is recommended that the basin shall be declared as the “Closed Basin”. The collaborative relationship between the provinces is something that is required more than water strategy. Strategies can always fall in place when the stakeholders repose unconditional trust in each other.

The United States Army Corps of Engineers (USACE) Philadelphia District (NAP), working through United States Africa Command (USAFRICOM), was tasked with supporting the Kingdom of Eswatini (formerly Swaziland) in developing a more robust water security strategy. Eswatini is a landlocked country located between South Africa and Mozambique. The country contains four physiographic zones, ranging from mountains to plains, with an equally variable climate. As a result of erratic rainfall, Eswatini suffered a severe drought in 2015 and 2016. NAP’s integrated water resource management approach included modeling of both surface water and groundwater resources. Surface water models of the upper reaches of the Mbuluzi River were developed using the Hydrologic Engineering Center’s river analysis system (HEC-RAS) and hydrologic modeling system (HEC-HMS). A three-dimensional conceptual site model of the country’s subsurface conditions was created using Aquaveo’s groundwater modeling system (GMS). The Eswatini Department of Water Affairs maintains a database of approximately 1,700 boring logs, which was used to develop the conceptual site model. The models were used as teaching tools during a September 2019 in-country training workshop and to inform the expansion/improvement of data collection systems. Future work includes development and expansion of these models and assistance with the country’s master planning strategy.

Urbanization is the world development trend after World War Two, which is more rapid in the developing countries in the past decades. For this reason, lots of megacities have been formed, and Shenzhen City in southern China is one of them. Due to rapid urbanization and social development, megacity surface has been changed dramatically, such as higher density of road network, more complex spatial structure of high buildings, residential areas, and factories. Furthermore, more underground drainage system was built to adapt the increasing flood quantities. For this reason, the flood hydrological process has been altered largely, and observation to the flood hydrological process under this changing environment is imperatively needed for better flood hydrological modeling and adaptation to the changed flood responses. In this study, flood hydrological process observation has been tried in Shenzhen City in the past years in the area where urban flooding is serious and frequent. The hydrological variables observed includes inundation depth and range, flow velocity, and precipitation. Precipitation observation was done by automatic rain gauges and weather radar, while the other variables are observed semi-automatically by field survey. Hydrological processes of several flood events were observed and the data collected. Based on these observation, the hydrological formation processes is analyzed and summarize, which is quite different from that in an undisturbed watershed. This finding is very helpful for proposing the adaptive hydrological model for simulating/forecasting urban flooding.