The water utilities are under big pressure to guarantee water access to their customers with the right level of service and quality due to challenges such as climate change, aging infrastructure, water scarcity, and growing populations, which put pressure on their operations. The scientific community has worked intensively over the last years to propose solutions and alternatives for the utilities to improve their operation and management in order to overcome these challenges. This paper aims to review scientific contributions to this field. The result shows increasing awareness from the scientific community in this topic which translates into a growing number of publications since the beginning of the current century. This paper analyzes the evolution of the publications, identifies the main countries and institutions working in this field and their scientific relationships over time. It also identifies the main keywords in the literature, which are grouped into three main topics: water quality, water management, and water optimization. The development of smart technologies is accelerating the scientific production towards the topic of water optimization, which is acquiring more importance over the last years. Future trends of research are related to identifying specific challenges per country and the specific solutions proposed by the scientific community to address them and its feasibility to be applied in other places.

The central part of Chile has been in severe unprecedented drought for more than ten years, becoming a water-stressed area. ESVAL, one of the main water utilities in the Chilean water sector, is responsible for delivering potable water to the population and securing long-term supply in the vast majority of this area. In order to achieve this goal, ESVAL is implementing different measures, with pressure management being one of them. This paper aims to describe the works executed in La Calera city to implement a new advanced pressure management scheme on an existing pressure-reducing valve with two main targets: reducing leakage and improving the level of service to the customers. The results show that advance pressure management generates a 10.12% reduction in the minimum night flow while, at the same time, helping to improve the level of service to the customers reducing the number of times pressure falls below the minimum target set by ESVAL by 52%. It is concluded that pressure management facilitates quick water savings by optimizing the performance of existing pressure-reducing valves.

Water is an essential element for life

Potable water utilities are currently making great efforts to reduce leakage rates and assure long-term supply to the population due to the challenges of climate change, growing population and water shortage scenarios that have been on them over the last years. One of the most employed methods to reduce leakage includes the installation of pressurereducing valves along the water distribution network and the utilization of pressure management schemes. Pressure management includes different types of control models, which are applied according to the requirements of each site. The most advanced and sophisticated scheme is critical point control, which relies on a flow signal from a measuring device or online communication between the critical point and the valve. This paper proposes the utilization of a seasonal autoregressive integrated moving average, or the SARIMA model, to correlate pressure at the outlet of the valve and pressure on the critical point of the area supplied, aiming to set a fixed pressure in the critical point. The SARIMA model is developed according to historical data logged in the field and then validated. Later, the SARIMA model was tested on a real location in the village of Noja, Spain. The analysis of the field test results prove that the proposed model is feasible to be used since there is no significance difference between the target values set in the critical point and the real values measured in the field. The research proves that the SARIMA model can be used as an alternative for critical point control in water distribution networks when no flow signal is available or when communication between the critical point and the pressure reducing valve is not an option.