Decision Support Tool for Design and Reliability Assessment of Water Distribution Networks - Pattern Recognition for Reliability Assessment of Water Distribution Networks - page 261

The hydraulic reliability diagrams have been further drawn for each of the six networks,
which are shown in Figures 9.11a to 9.11c.

1.00 1.00

Underconnected Underconnected Underconnected Underconnected

0.90 0.90

0.80 0.80

0.70 0.70

0.60 0.60

0.50 0.50

0.40 0.40

0.30 0.30

0.20 0.20

0.10 0.10

Overconnected Overconnected Overconnected Overconnected

0.00 0.00

0.00 0.20 0.40 0.60 0.80 1.00 0.00 0.20 0.40 0.60 0.80 1.00

1-ADF 1-ADF

Figure 9.11a HRD: layout nr.1727 (the cheapest) - left, layout 3307 (the most reliable) - right

1.00 1.00

Underconnected Underconnected Underconnected Underconnected

0.90 0.90

0.80 0.80

0.70 0.70

0.60 0.60

0.50 0.50

0.40 0.40

0.30 0.30

0.20 0.20

0.10 0.10

Overconnected Overconnected Overconnected Overconnected

0.00 0.00

0.00 0.20 0.40 0.60 0.80 1.00 0.00 0.20 0.40 0.60 0.80 1.00

1-ADF 1-ADF

Figure 9.11b HRD: layout nr.691 (the cheapest) - left, layout 757 (the most reliable) - right

1.00 1.00

Underconnected Underconnected Underconnected Underconnected

0.90 0.90

0.80 0.80

0.70 0.70

0.60 0.60

0.50 0.50

0.40 0.40

0.30 0.30

0.20 0.20

0.10 0.10

Overconnected Overconnected Overconnected Overconnected

0.00 0.00

0.00 0.20 0.40 0.60 0.80 1.00 0.00 0.20 0.40 0.60 0.80 1.00

1-ADF 1-ADF

Figure 9.11c HRD: layout nr.353 (the cheapest) - left, layout 962 (the most reliable) - right

The diagrams depict clearly that the cheapest networks (on the left) are less reliable than
those on the right. Amongst the three most reliable networks, the layout nr.3307 would
possible qualify as the best overall, having the least number of pipes whose failure causes
severe damage. The layout nr.962 could also qualify to win in case the problem of three
distinct pipes can be solved. The failure of any of these pipes will be causing the loss of
demand in the range of 30 to 40 %, which can be seen both in Figure 9.11c (right) and in the
Tables 9.12 and 9.13. Table 9.12 shows the number of pipes causing the loss of demand in
categories of 10%, while Table 9.13 shows the equivalent percentage. Both confirm the
impression obtained from the HRDs that the layout nr.3307 is the most reliable one, with
only two pipes causing the demand loss above 10%.