الفهرس 
Types of agricultural drainage water reuseOnly 14 pages are availabe for public view
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Abstract
The dependence on the drainage water became an essential element to
face the gap between water resources and water requirements due to the
limitation of water resources and the gradual increase in water demand.
Reusing the drainage water requires precise definition of the amount and
locations of the reuse to mitigate the associated environmental problems due to
the pollution of such drainage water.
Currently, the trend of reusing the drainage water in Egypt is moving
towards the direct dependence on polluted drainage water at tail end regions,
which decrease the quantitative and qualitative equity of water distribution.
The current study aims to improve the situation at tail end regions by
mixing the drainage water with the surface water at head reaches while
maintaining environmental standards, and it was applied in Mit Yazid canal,
which is a main canal in Middle Delta.
The study depended on using simulations and water quality models (HECRAS model) to make sure that the main canal can convey the flow with lifted
drainage water and the environmental standards are maintained.
The scope of the current study is the impact of mixing the drainage water
with the fresh; the positive water resources impact and the negative
environmental impact, and how to reach the balancing point to get the maximum
benefits from such application.
The study was applied during both summer and winter seasons, and
different scenarios were investigated during each season. During summer season,
the drainage water was lifted from six drains to the main canal. Two scenarios
with total lifted drainage water equals 10.50 and 12.0 m3
/s were investigated.
During winter season, the drainage water was lifted from 13 Drains to the main
canal and five branch canals at the head of the irrigation network. Three
scenarios with total lifted drainage water equals 8.50, 10.00 and 12.50 m
3
/s were
investigated. The results showed that the first scenarios during summer and winter
seasons could satisfy water quality standards. For the second scenario during
summer season, NH₃ parameter only exceeded the standard values at the end of
the investigated reach and partial treatment was suggested to satisfy water quality
standards. For the second scenario during winter season, only NH3 and COD
parameters exceeded the standard values at the end of the investigated reach and
partial treatment was suggested to satisfy water quality standards. For the third
scenario during winter season, NH3, COD, and NO3 parameters exceeded the
standard values at the end of the investigated reach.
The results showed that it is possible to considerably increase the flow to
downstream areas while maintaining WQ standards.