• Effective cross sectional area (with 15mm free board): 19,250mm²
• Flow capacity: 363 litres/min
• Minimum recommended fall: 1:500
• Minimum downpipe size: 
• Circular: 115mm
• Rectangular: min. cross sectional area of 10,600mm²

Catchment area per downpipe based on the above flow capacity is given in Table 3.1.H. Use Table 3.1B (Section 3.1.4) to determine the Rainfall Intensity to be used.

Table 3.1.H