Page 10 - Water Pollution Management - Management Plans - Understanding your Risk

Step 4 Determine the mean annual peak flow

Peak Flow Litres/Second/Hectare

Soil Type Annual Rainfall (mm)

<600 600 - 800 800 -1200 1200 - 1600 1600 - 3200 >3200

1 0.3 0.4 0.6 0.9 1.7 2.4

2 1.4 1.8 2.8 4.1 7.7 10.8

3 2.6 3.4 5.2 7.7 14.4 20.1

4 3.3 4.4 6.7 9.9 18.6 26.0

5 4.2 5.5 8.4 12.4 23.3 32.7

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