System Modeling, Optimization, and Analysis of Recycled Water and Dynamic Storm Water Deliveries to Spreading Basins for Urban Groundwater Recharge

Abstract

To bolster freshwater supplies, water managers are increasingly interested in recharging groundwater using storm water and recycled water. However, such multisupply groundwater recharge projects are hindered by the lack of planning tools to evaluate system design costs and trade‐offs. This study presents modeling advancements that provide enhanced insights into multisupply spreading basin systems (i.e., spreading basins that accommodate both advanced treated recycled water and dynamically available storm water), a form of managed aquifer recharge. The model identifies system designs that optimize infrastructure life cycle cost and water volumes infiltrated for groundwater recharge. To illustrate the model's application under realistic conditions, we present a case study of Los Angeles, California. In this case study, we find that competition between storm water and recycled water for spreading basin use is relatively minor. Moreover, compared to systems based on existing conservative assumptions, our methods identify optimal dynamic system designs that are 5%–20% more cost‐effective, primarily resulting from higher water recycling facility utilization. Overall, this approach, which considers the dynamic nature of storm water availability and variable recycled water production, can inform water planners of the cost, water volume, and energy trade‐offs associated with different multisupply spreading basin system designs, including varying levels of centralization.

Hydrophilic trace organic contaminants in urban stormwater: occurrence, toxicological relevance, and the need to enhance green stormwater infrastructure

“…12,[30][31][32] In the face of global water scarcity, urban stormwater is increasingly valued as a currently underused freshwater resource. [33][34][35] The capture, treatment, and recharge of stormwater runoff can augment urban water supplies and diversify urban water supply portfolios. [34][35][36] However, safe…”

Transformation of N-Methylamine Drugs during Wastewater Ozonation: Formation of Nitromethane, an Efficient Precursor to Halonitromethanes

“…Intensifying water scarcity has led to increased interest in potable reuse. , Water reuse processes frequently employ ozone, either as pretreatment before microfiltration and reverse osmosis (RO) to prevent membrane biofouling or followed by biologically activated carbon (O 3 /BAC) as an alternative to RO. , O 3 /BAC is growing in popularity as it is generally less energy intensive than RO and does not generate brine. , Ozone is an effective oxidant for most pharmaceutical compounds in wastewater and other trace contaminants in wastewater − and has been implemented in Europe to oxidize micropollutants prior to wastewater discharge into the environment . It generally reduces the formation of regulated disinfection by-products such as trihalomethanes and haloacetic acids during subsequent chlorination .…”

“…4,5 O 3 /BAC is growing in popularity as it is generally less energy intensive than RO and does not generate brine. 4,5 Ozone is an effective oxidant for most pharmaceutical compounds in wastewater and other trace contaminants in wastewater 6−9 and has been implemented in Europe to oxidize micropollutants prior to wastewater discharge into the environment. 10 It generally reduces the formation of regulated disinfection by-products such as trihalomethanes and haloacetic acids during subsequent chlorination.…”

Urban Stormwater to Enhance Water Supply

“…For example, systems that deliver recycled water to existing stormwater spreading basins in Los Angeles would take advantage of both the spreading basins' significant unused capacity and the city's substantial potential to produce recycled water, thereby creating an integrated, cost-effective groundwater replenishment system. 27,61 As illustrated in Figure 3, the complexity of these integrated systems in terms of capacity and location requires decisionsupport methods to evaluate various design options for bringing recycled water to underutilized stormwater spreading basins and to optimize these designs by engineering considerations such as infrastructure life cycle costs, energy use, and water quantity and quality. An example for the City of Los Angeles illustrates trade-offs between centralized and decentralized configurations and highlights the potential for decentralized inland systems to deliver up to 44 500 acre-ft/yr of recycled water to spreading basins at costs significantly less than a centralized system delivering recycled water from the coast.…”

“…Based on Los Angeles’ projections for water import costs, the estimated economic value of recharged water may be $1100 per acre-ft ($0.89/m 3 ) or more based on lifecycle analysis. , Projects with costs below these values are economically viable based solely on the water supply benefit, and cities are more likely to pursue these projects without seeking funds from external partners. However, caution must be exercised in comparison with cost of current water supplies, as much of those costs were heavily subsidized in the past and there really is not new water to be had at the old rates.…”