Minimum Pipe Slope at full Capacity for Gravity Sewer lines

Sewer design standards  and specification 

DN dia mm	V=0.80 m/sec		V= 0.73 m/sec
150	0.0063	0.63%	0.0056	0.56%
200	0.0044	0.44%	0.0039	0.39%
250	0.0033	0.33%	0.0029	0.29%
300	0.0026	0.26%	0.0023	0.23%
350	0.0021	0.21%	0.0019	0.19%
400	0.0018	0.18%	0.0016	0.16%
450	0.0016	0.16%	0.0014	0.14%
500	0.0014	0.14%	0.0012	0.12%
600	0.00109	0.109%	0.00096	0.096%
700	0.0009	0.090%	0.0008	0.080%
800	0.00077	0.077%	0.00068	0.068%
1000	0.00058	0.058%	0.00051	0.051%
1200	0.00047	0.047%	0.00041	0.041%
1400	0.00039	0.039%	0.00034	0.034%
1600	0.00033	0.033%	0.00029	0.029%
1800	0.00028	0.028%	0.00025	0.025%
2000	0.00025	0.025%	0.00022	0.022%
2400	0.0002	0.020%	0.00018	0.018%