Smart Zone-Based Water Pressure Management System

Solution Overview

Cape Town implemented smart process controllers that enable zone-by-zone water pressure management to significantly reduce water consumption.[6][7] This approach addresses critical infrastructure challenges through advanced pressure control technology deployed across an extensive network of pressure management zones.[1] The system played a vital role in helping the city avoid 'Day Zero' during the severe 2015-2017 drought by halving municipal water use.[2]

Technical Components

The implementation incorporated multiple advanced pressure control technologies working in coordination across the water distribution network. JOAT Group recommended i2O's Pressure Optimisation solution, oNet, which offered the ability to precisely control critical point pressure at pressure reducing valves (PRVs) and to manage the city's water more effectively through intelligent, self-learning technology.[3] Utilitec Services, in partnership with the City of Cape Town, installed the Regulo PRV controller, an electronic controller which may be retrofitted to most models of hydraulic PRV.[4] The Regulo records the inlet, outlet and critical point pressures, flow rate and valve position at 15 minute intervals.[4] The Regulo has a dedicated internal modem and battery, allowing it to be deployed in underground chambers without the need for an external power supply or kiosk.[4] The Regulo is capable of implementing both time and flow modulated control and can be remotely configured through the Technolog software platform.[4] The Technolog software platform, Utilisoft, provides a web based interface that allows the City of Cape Town to remotely manage their advanced pressure control systems.[4]

Implementation Details

Cape Town established 170 pressure management zones covering 68 percent of the water network as of June 2021.[1] The City of Cape Town has a well-established pressure management programme, with over 200 pressure management zones (PMZs).[4] Utilitec Services, a Technolog group company, has been working in partnership with the City of Cape Town to install and commission over 100 advanced pressure control systems.[4] The City of Cape Town has installed over 100 advanced pressure control systems, resulting in an estimated saving of 21 million m3 of water per annum.[4] The City of Cape Town was continuing to expand its advanced pressure management programme, with a further 50 systems planned for installation in 2017.[4] Cape Town's ultimate plan is to have about 90% of the water network under pressure management with more than 300 pressure management zones installed.[5] JOAT ran a two-phase trial of oNet in the Eersterivier PRV zone, which comprises 89.3km of mains and 6,218 connections.[3]

Benefits and Impacts

The pressure management programme addressed critical infrastructure challenges, as an average mains burst frequency of 21 per 100km per year and a 21% leakage rate meant the City of Cape Town needed to find more effective ways of managing pressure in its water distribution network.[3] In the first phase, oNet successfully maintained a constant critical point pressure of 27m, which had previously averaged 34.5m during peak periods and 37m in off-peak.[3] In the second phase, oNet was set to target critical point pressures of 27m during peak periods and 23m during off peak.[3] In the Gugulethu DMA, implementing advanced pressure control reduced the average daily flow from 11,000 m3/day to 7,000 m3/day, a saving of 4,000 m3/day.[4] The advanced pressure control programme has resulted in a significant reduction in burst frequencies, saving the City of Cape Town an estimated £1.2 million per annum in repair costs.[4] The remarkable efforts of Capetonians to reduce their water consumption, and the City of Cape Town's pressure management programme, successfully halved municipal water use and helped the city avoid 'Day Zero'.[2]

Climate Adaptation Relevance

This pressure management technology directly addresses water scarcity challenges intensified by climate change, as demonstrated during the 2015-2017 drought when the system helped prevent complete reservoir depletion. The intelligent pressure control approach enhances municipal resilience to extended drought periods by maximizing water conservation through leak reduction and optimized distribution network performance. By reducing water losses and enabling more efficient resource allocation across pressure management zones, the system strengthens the city's capacity to withstand future climate-driven water stress events.

Business Analysis

The implementation demonstrates a financially viable approach to water infrastructure optimization, with the City of Cape Town achieving an estimated £1.2 million per annum in repair cost savings through reduced burst frequencies.[4] The advanced pressure control programme generated substantial operational returns through water conservation, saving an estimated 21 million m3 of water per annum across over 100 installed systems.[4] The partnership model between Utilitec Services, a Technolog group company, and municipal authorities enabled systematic deployment and commissioning of advanced pressure control systems.[4] The scalable nature of the technology, with retrofitting capabilities for most hydraulic PRV models and remote management through web-based platforms, supports cost-effective expansion across additional pressure management zones.[4] The planned expansion to 300 pressure management zones covering 90% of the water network indicates sustained municipal investment in this infrastructure optimization approach.[5]