Appendix 2.

Rating of infiltration rates for surface irrigation

Infiltration rates (cm/h)	Suitability for surface irrigation
<0.1	Unsuitable (too slow) but suitable for rice
0.1–0.3	Marginally suitable (too slow); marginally suitable for rice
0.3–0.7	Suitable; unsuitable for rice
0.7–3.5	Optimum
3.5–6.5	Suitable
6.5–12.5	Marginally suitable (too rapid); small basins required
12.5–25	Suitable only under special conditions for very small basins
>25	Unsuitable (too rapid); suggested for overhead methods only

Adopted from Landon [71].