Non-Revenue Water Reduction in Livingstone City

Southern Water and Sewerage Company (SWSC)

Livingstone is the largest service area for Southern Water and Sewerage Company, with a total of 16,548 connections. Understandably, the city also harboured the most losses for the utility company. Old, dilapidated water network has played a major setback in NRW reduction in the past 5 years. WAVEplus trainings introduced simple NRW reduction strategies which helped to almost half the NRW level from 60% to 33% in 3 years.

Contact: Namooya Hamoonga | cmbilima(at)gmail.com | Southern Water and Sewerage Company (SWSC)

Lessons Learnt

Livingstone managed to implement a NRW reduction strategy by simply organising its staff and zoning its service area to focus on the areas that were badly hit. By migrating from the norm of presenting NRW in percentage form into cubic meters lost per kilometer length of pipe, the water audit team was able to target its interventions.

Objectives

The main objective of the project was to reduce NRW by half from 60% that was prevailing to around 30%. Stepwise objectives were followed to:

  • Divide the city into 10 technical zones which were referred to as District Metered areas (DMAs) and metering was introduced
  • Synchronise the DMAs with billing areas. Quantify the consumption for the unmetered areas using the metered tariff 5
  • Establish a water audit section

Project Description

The Livingstone Town Billing System was adjusted and bulk meters and control valves were installed. A Water Audit Team was established to: 

  • Conduct Minimum Night flows to establish real/apparent losses and to calculate NRW.
  • Use of m3 /km/day or m3/Number of connections/hour as the best practice to compare zones
  • Check of consumption in the system and follow-up on the ground to detect bypasses and/or illegal connections and connections that are not being billed
  • Establish the best NRW calculation on unmetered customers
  • Report and follow up on all reported leaks
  • Routine spot checks on meter readers to cross check the correctness of the readings

Results

  1. With the above measure, the city is now better able to compute NRW using the IWA water balance
  2. NRW was reduced from 60% to 33 % during the period 2008 to 2011
  3. Additionally, the water audit team discovered a number of illegal connections and meter bypasses which were contributing to apparent losses

Sustainability

Despite the city being at 87% metering, SWSC was able to harness results from this project. With the success of the Livingstone project, SWSC is now working to replicate this in the other towns.

WAVE Impact

In an attempt to manage the NRW, Livingstone management resolved to lead the process following a series of face-to-face and online trainings in NRW offered by the WAVEplus programme. It was anticipated that since this was the service area, the impact would be immense. Participants of the NRW training included the implementation of NRW reduction strategies as part of their work plan.