1. District Metered Areas
DMA creation and management

2. Contents
Introduction DMA Creation DMA Management

3. Introduction

4. District Metered Areas
A District Metered Area (DMA) is a hydraulically isolated and completely metered section of the complete water network
Introduction

5. DMAs for NRW management
To be able to analyse the level of NRW, the problem should be divided into manageable pieces. By creating DMAs as NRW reduction/management pilot areas, NRW can be analysed in more detail and the effect of NRW reduction measures monitored
Furthermore, a DMA serves as a good tool to make a business case for NRW reduction, because it allows for:
Faster results (in comparison to working with the complete network)
Action – even when the company is not yet fully supportive of the approach, as a smaller investment and number of staff is needed
The creation of commitment to NRW management by showing quick results in a small area Less investment costs
Introduction

6. 2. DMA Creation

7. DMA selection criteria
For the creation of DMAs, the water distribution network should be sectioned in hydraulically isolated and separately measured zones. Important criteria for selecting a DMA include:
Knowlegde of network and assets: (verified) GIS data is essential
‘High NRW’ area (commercial and/or physical losses)
Not too big, not too small, plus/minus 500 connections
Easy isolation (clearly visible topographical points that can serve as boundaries for the DMA, such as rivers, roads, railway tracks, etc.,) which helps to:
Save in investment costs
Make it easier to identify the customers connected in the zone
Ideally, water availability 24/7 and good pressure.(a lack of water and low pressure levels undermine the reliability of the meter readings)
No immediate plans for network changes
DMA creation

8. DMA creation To isolate the DMA, it is required to:
Further verify the GIS data
Install meters and valves in tamper-proof chambers on all incoming and outgoing lines
Verify, by closing the valves on incoming lines and checking whether or not customers still receive water, which customers are located in- or outside of the DMA. This exercise will reveal:
Whether the GIS has captured the network as it truly is
Which customers should be in –or excluded from the DMA’s customer base
Results from water balance calculations can also indicate (for instance by showing particularly high or low NRW) incoming or outgoing lines that were left out and still need to be disconnected or metered.
DMA creation

9. Assets to install Valve Bulk water meter
To be able to close the DMA (and verify whether it is hydraulically isolated)
Bulk water meter
Measures the quantity of water flowing in and out of the area
Strainer (before the water meter)
To collect the dirt out of the water main and protect the water meter
Straightener??????
Bring back the turbulence in the water
Valve before or after meter, at what distance???? Etc
DMA creation

10. 3. DMA Management

11. Caretaker approach A caretaker is:
Responsible for the supervision of NRW reduction plans and activities in a specified service area, including standard operating procedures such as:
Opening/closing the boundary valves (DMA must always be closed)
Network planning
Leak detection and repair
Monitoring the quality of repairs and installation of new house connections
Execute preventative maintenance programmes
Water meter calibration (and necessary replacement)
The search for illegal connections
The “eyes and ears“ of the water company in this area
A point of reference for the customers in this area
Informing customers on network activities
Taking note of – and action on - customer complaints
Report on experience in the area (NRW, customer satisfaction, illegal connections, repair, maintenance and needed materials, etc.) to a supervisor
Advise the supervisor on management plans and activities that need third parties

12. What does a Caretaker need?
A caretaker needs:
A team (of plumbers, meter readers, GIS specialist etc.) with whom the activities in the area can be performed
To be given due status and autonomy to be able to steer his team
To be given (timely) access to needed materials and people to be able to perform the planned activities in the area
Experience with NRW and leading a team
To be held accountable