What is Non-Revenue Water?
Non-Revenue Water (NRW) represents the difference between the amount of water put into a distribution system and the amount of water billed to customers. In India, NRW levels often exceed 40%, representing a significant economic and environmental loss.
Components of NRW
NRW consists of two main categories:
Physical Losses (Real Losses)
- Leakage on transmission and distribution mains
- Leakage on service connections up to customer meters
- Storage tank overflows
Commercial Losses (Apparent Losses)
- Unauthorized consumption
- Customer meter inaccuracies
- Data handling errors
- Billing irregularities
Technical Strategies for NRW Reduction
1. Pressure Management
Implementing pressure reducing valves and establishing District Metered Areas (DMAs) to optimize system pressure and reduce leak rates.
2. Active Leak Detection
Systematic programs using acoustic sensors, correlators, and ground-penetrating radar to identify and locate leaks before they become visible.
3. Asset Management
Risk-based pipe replacement programs focusing on aging infrastructure and pipes with high failure rates.
Effective NRW management requires a systematic approach combining technology, skilled personnel, and sustained commitment from utility management.
Case Study: DMA Implementation
In a recent project with Pune Municipal Corporation, we established 15 District Metered Areas covering 200,000 connections:
- Baseline NRW: 45%
- Target NRW: 20%
- Achieved NRW: 18% within 18 months
- Water saved: 25 MLD
- Annual savings: ₹15 crores
Technology Solutions
Smart Water Meters
AMR/AMI systems provide real-time consumption data and enable rapid detection of abnormal usage patterns.
SCADA Integration
Centralized monitoring systems track flow, pressure, and quality parameters across the distribution network.
GIS Mapping
Digital mapping of infrastructure assets enables better planning and faster response to network issues.
Implementation Framework
Successful NRW reduction programs follow a structured approach:
- Baseline Assessment: Comprehensive water audit and NRW quantification
- Infrastructure Mapping: GIS-based asset inventory and condition assessment
- DMA Establishment: Network sectorization and metering installation
- Leak Detection: Systematic survey and repair programs
- Pressure Management: Installation of control valves and optimization
- Performance Monitoring: Continuous tracking and improvement
Economic Benefits
NRW reduction delivers substantial economic benefits:
- Reduced raw water abstraction costs
- Lower treatment and pumping costs
- Deferred capital investment in new sources
- Improved customer satisfaction and revenue
- Enhanced system reliability