TITLE:
A Study on the Causes of Sediment Accumulation in the Drainage Systems
AUTHORS:
Cengiz Koç, Ebru Yilmaz
KEYWORDS:
Drainage Canal; Sediment; Structure; Design Project; Turkey
JOURNAL NAME:
Journal of Water Resource and Protection,
Vol.6 No.4,
March
20,
2014
ABSTRACT: Accumulation
of sediment and silt in the drainage canals is undesirable, yet inevitable
occurrence in the course of the use and operation of any drainage canal
network. In this study, D-25 drainage canal group, taking place in the Nazilli
irrigation system with an area of 1165 ha is the only system where all planned
activities have been completed. It has been determined that the drainage system
was constructed according to original drainage project. The depth of
accumulated sediment in the drainage canals in the research area was determined
from the difference between the measured elevation and the elevation given in
the design projects. The reasons for siltation in the D-25 drainage canal group
have been studied by looking at the results of the elevation measurements made
in 2010-2012. The measurements made in D-25 drainage canal group showed that
there were significant differences between the actual structure (bridge,
culvert, and conduit) bottom elevations and the elevations given in the design
projects. In addition, the length of some canals would not coincide with the
design project either. 83.3% (93.3% in length) of the canals had differences in
structure bottom elevations. Of the total 55 structures 45 (81.8%) had a 0.10 m
or more difference in bottom elevation from the project. Of the erroneous
structures 73.3% had an average of 0.40 m, and 26.7% had an average of -0.25 m
difference in bottom elevations from the design projects.