Page 60 - Water and DSİ

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CHAPTER IV - IRRIGATION
Thence, it is absolutely necessary to have storage facilities in order to ensure agricultural water
supply as well as other necessities e.g., domestic& industrial supply, and hydroelectric energy.
In Turkey, 80% of the irrigation water is derived
from surface sources; the 20% is from
groundwater. DSİ applies 3 planned irrigation
management works; 1) planning before irrigation,
2) monitoring water distribution during irrigation,
and 3) evaluation after irrigation. Irrigation ratios
and irrigation efficiencies are used to determine
performance criteria of irrigation facilities. The
irrigation ratio and the irrigation efficiency have
been 65% and 45% respectively which reflects
average long term figures.
The reasons of low irrigation ratios are; fallowing
(12%), rainfed cultivation (27%), inadequacy of
water resources (8%), insufficient irrigation
structures (8%), high watertable (2%), salinity and alkalinity (3%), inadequate maintenance (2%),
topographic conditions (4%), economic & social problems (20%), and other reasons such as
irrigation areas converted to industrial & settlement areas (16%). These results are obtained from
the assessments of DSİ irrigations, the size of which is more than 1,000 ha. Since the majority of
DSİ irrigations open gravity canals, the target is to raise irrigation efficiency up to 50%.
The Code 6200 instructs that the whole actual operation and maintenance expenditures incurred
by DSİ for irrigation investments are subject to be paid back by beneficiaries as operation and
maintenance charges. Operation and maintenance charges are determined each year by Council of
Ministers’ decree. Code 6200 authorizes Council of Ministers also to discount in operation and
maintenance charges. The Ministers’ decree dated 7 May 2001 determined the recovery payment as
1.5-7.5 TL/ha starting from 2002. The reimbursement period is 11 years.
In addition, investment costs as well as expropriation cost for DSİ developed irrigation facilities
are to be recovered by beneficiaries pursuant to Code 6200. Installments payments of cost
recovery prices are updated in certain periods by Governmental Decrees. But the last update was
made on 7th May 2001 with Prime Ministry Approval and annual investment cost recoveries has
been determined between 1,500-7,500 TL/ha. Recovery payment period is average 11 years.
Sediment accumulation and weed on the canals hinder the water conveyance. Mechanical clearance
is to be preferred to eradicate these problems.
Before the irrigation season water structures (canals, check gate, gauging facilities, and intake
structure) are to be prepared by maintenance.
Rehabilitation of Irrigation Facilities
Management of irrigation facilities are transferred to water user organizations, some of which are
difficulty in financing maintenance services. In this regard, conditions of some irrigation facilities
can be set out as follows:
Some Irrigation facilities in poor quality have been transferred to WUOs.
Because some WUOs were not be able to repair and maintain, the conditions of irrigation
facilities became worse.
Wear and tear condition of some irrigation facilities is so poor in quality that they cannot
be restored simply by repair and maintenance.
Water Resources and Runoff
For Agricultural Irrigation
80% Surface Water Resources
%15 Pumping
%65 Gravity
20% Ground Water Resources
%3 Augmentation of Gravity
%17 Extraction via pumping by
Groundwater Irrigation Cooperatives