Assessment of Rainfall Intensity Equations Enlisted in the Egyptian Code for Designing Potable Water and Sewage Networks

Table 4

Relation between storm duration (min) and rainfall intensity ratios (Groups X and Y).

Time (min)	Duration (min)	Rainfall intensity ratio
		Group X	Group Y
(10 min < duration < 20 min)	6	1.529	1.654
	12	1.295	1.401
	18	1.150	1.244
(20 min < duration < 120 min)	24	0.993	1.075
	30	0.848	0.918
	36	0.742	0.803
	42	0.663	0.718
	48	0.600	0.649
	54	0.548	0.593
	60	0.506	0.547
	66	0.471	0.509
	72	0.441	0.477
	78	0.416	0.450
	84	0.392	0.424
	90	0.372	0.403
	96	0.354	0.383
	102	0.339	0.367
	108	0.325	0.352
	114	0.312	0.337
	120	0.300	0.325