Carry-off Irrigation


Irrigation systems in semi-arid regions with low humidity.


irrigation, water tables, salinization

Predecessor Patterns

. . . Implementing this pattern will help maintain Downstream Water Volume if flushing the soil returns water from whence it came.

Problem Summary

When irrigation has no carry-off system, the evaporating water deposits a gradual build-up of salinization, which is eventually damaging to plant life.


This problem is aggravated when water is scarce and high frequency, low volume irrigation is utilized. This increases the amount of water that evaporates in relation to the amount of water that percolates through the soil, flushing it of mineral residue. As the mineral content of the soil increases, eventually commercially valuable plants cannot grow well because:
  1. the salts dehydrates the plant since the plant can't extract water from the salty soil,
  2. the salts accumulates in the plant severely damaging its tissues.

Solution Summary


Reduce salts that accumulates per unit time by:

  1. reducing the frequency of irrigation and on occaision increasing the volume of water to flush the soil into the water table
  2. increasing the porocity of the soil, and
  3. mulching the soil (depositing a substance that separates soil from air).

Successor Patterns

(none) . . .


  1. (none)


Ken Asplund and Gary Swift, March, 1973; last revision 7/16/96
Last updated:

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