The strong greenhouse gas nitrous oxide (N2O) can be emitted from wastewater treatment systems as a byproduct of ammonium oxidation and as the last intermediate in the stepwise reduction of nitrate to N2 by denitrifying organisms. A potential strategy to reduce N2O emissions would be to enhance the activity of N2O reductase (NOS) in the denitrifying microbial community. A survey of existing literature on denitrification in wastewater treatment systems showed that the N2O reducing capacity (VmaxN2O/N2) exceeded the capacity to produce N2O (VmaxNO3/N2O) by a factor of 2e10. This suggests that denitrification can be an effective sink for N2O, potentially scavenging a fraction of the N2O produced by ammonium oxidation or abiotic reactions.
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Assessment of future water availability under climate change, considering scenarios for population growth and ageing infrastructure
Climate change is likely to cause higher temperatures and alterations in precipitation patterns, with potential impacts on water resources. One important issue in this respect is inflow to drinking water reservoirs. Moreover, deteriorating infrastructures cause leakage in water distribution systems and urbanization augments water demand in cities. In this paper, a framework for assessing the combined impacts of multiple trends on water availability is proposed.
Adapting to urban flooding: a case of two cities in South Asia
Cities in South Asia are experiencing storm water drainage problems due to a combination of urban sprawl, structural, hydrological, socioeconomic and climatic factors. The frequency of short duration, high-intensity rainfall is expected to increase in the future due to climate change. Given the limited capacity of drainage systems in South Asian cities, urban flooding and waterlogging is expected to intensify. The problem gets worse when low-lying areas are filled up for infrastructure development due to unplanned urban growth, reducing permeable areas.
A knowledge discovery framework to predict the N2O emissions in the wastewater sector
Data Analytics is being deployed to predict the dissolved nitrous oxide (N2O) concentration in a full-scale sidestream sequence batch reactor (SBR) treating the anaerobic supernatant. On average, the N2O emissions are equal to 7.6% of the NH4eN load and can contribute up to 97% to the operational carbon footprint of the studied nitritation-denitritation and via-nitrite enhanced biological phosphorus removal
process (SCENA). The analysis showed that average aerobic dissolved N2O concentration could significantly vary under similar influent loads, dissolved oxygen (DO), pH and removal efficiencies. A combination of density-based clustering, support vector machine (SVM), and support vector regression (SVR) models were deployed to estimate the dissolved N2O concentration and behaviour in the different phases
of the SBR system.
Baseflows Cyclone Idai Flood Response using mWater
Evaluating the effect of different operational strategies on the carbon footprint of wastewater treatment plants – case studies from northern Poland
The objective of this study was to perform carbon footprint (CF) analysis for two municipal WWTPs located in northern Poland. Slupsk WWTP is a large biological nutrient removal (BNR) facility (250,000 PE) which benefits from on-site electricity production from biogas
Climate Smart Utilities Case Stories
Climate impact from nitrous oxide emission – a Danish case
One of the most important roles of WWTPs is the removal of nitrogen and phosphorous based nutrients, which otherwise, in large concentrations, leads to eutrophication of the receiving water bodies. In the later decades, EC’s nitrates directive and the Danish national water environmental strategies have hence led to a significant reduction of nutrients in the WWTP effluents.
Adaptation and mitigation synergies to improve sanitation: a case study in Morelos, Mexico
The management of wastewater is the fifth largest single source of CH4 emissions and the sixth of N2O. Options to improve sanitation within the Morelos State in Mexico were compared applying a modification of the IPCC guidelines to estimate greenhouse gas (GHG) emissions.
DROUGHT AND INFRASTRUCTURE A Planning Guide
This Drought Guide can be used to anticipate and prepare for the consequences of drought on infrastructure services. This guide was developed through the interagency National Drought Resilience Partnership (NDRP). It directs users to the National Integrated Drought Information System (NIDIS) (drought.gov) and other agencies’ information and decision tools.