Page 288 - Corrosion Engineering Principles and Practice

262 C h a p t e r 8 C o r r o s i o n b y W a t e r 263

The AWWA has developed a six-step procedure shown in Fig. 8.2
for the assessment and control of internal corrosion of water
distribution systems [3]. Although the application of this method
appears straightforward, working out the details for each system in
an actual network can be quite complex. The procedure specifically
focuses on older systems and does not consider corrosion prevention
for new systems. It assumes that corrosion is already present and

• Water quality impact
Document Extent and
Step 1 Magnitude of Corrosion • Piping deterioration
• Environmental issues

Determine • Water quality characteristics
Step 2 Possible Causes of • Susceptible piping
Corrosion • Workmanship and materials

• pH and alkalinity
Develop and • CaCO saturation
3
Step 3 Assess Corrosion Control • Inhibitors
Alternatives
• Material replacement

Evaluate Alternatives • Performance
Step 4 and Select Corrosion • Cost
Control Strategy • Side effects

Document Findings • Formal documentation
Step 5 in Engineering Report • Regulatory requirements

Implement Corrosion • Design, construction, start-up
Step 6 Control and Monitoring • Treatment monitoring
Effectiveness • Distribution system monitoring

FIGURE 8.2 Corrosion control program implementation flowchart.