Environmental Engineering Reference
In-Depth Information
however, groundwater use is largely unregulated and abstraction rates generally are
not known. The World Bank program conserves water in part by converting fixed
rotation delivery to water on-demand systems and by helping farmers shift to higher
value crops. Two of the program's success indicators are (1) improved “water
productivity,” defined as benefit or value per unit of water consumed by the
beneficiary farmers, and (2) reduced groundwater consumption for irrigation.
Riverside Technology, inc. (Riverside) was contracted by the World Bank to
process and analyze satellite imagery to estimate crop water use in selected sectors
of three large and economically important irrigation districts in the Oum Er Rbia
and Tensift river basins of Morocco. The Riverside team used surface energy
balance methodology to estimate and map actual evapotranspiration (ET) from
remote sensing data. The ET maps were the core foundation for additional analyses,
which estimated the water balance and groundwater use in pilot sector areas
selected for water efficiency improvements and for distributing a predictable (and
sustainable) allocation of surface water to farmers while limiting or reducing their
need for groundwater consumption. The results will also provide a baseline of water
use and water productivity for comparison with post-project conditions to assess the
impacts of the project intervention.
13.3 Climate and Water Availability in Morocco
Morocco's water resources are unevenly distributed and unreliable, and under a
changing climate, the country's water resources are predicted to become even more
scarce. The natural reductions of water supply are exacerbated by increasing demands
from Moroccan economic development and from an increasingly urban population.
Agricultural production and processing makes up 85% of Morocco's water use and
employs 40% of the workforce. The national agriculture strategic plan recognizes the
importance of agriculture and the direct correlation between the amount and season-
ality of rainfall and the national GDP (Ministry of Agriculture Morocco
2008
).
During drought years, rainfall in Morocco can be as little as one-third of the
“normal” amount. A pressing concern is how future demand for water will be met.
Groundwater pumping, already at 30% of total water use, is used for irrigation
expansion and to supplement surface irrigation water shortages (AquaStat Data-
base; FAO 2004), yet groundwater levels are falling rapidly in many regions.
Concerns about the future of Morocco's water resources have been widely
recognized. Arnell (
1999
) predicted that Morocco would shift from a medium to
highly water-stressed country
1
by 2025, with a 25-50% decrease in both maximum
monthly runoff and minimum annual runoff by 2050.
Water resources supply and management is one of Morocco's most important
national issues and is the subject of recent policy and national action plans. The issue
1
Water stress is defined by the ratio of withdrawals to renewable water resources with “medium”
stress in the range of 20-40% and “high” water stress when the ratio is over 40% (Arnell
1999
).
Search WWH ::
Custom Search