DESCRIPTION OF THE STUDY AREA AND DATA INVENTORY - Integrating GIS, Remote Sensing, and Mathematical Modelling for Surface Water Quality Management - page 108

equipment (sampling bottles, filter paper, field kits for measuring PH, temperature and EC). Figure (5-
15) shows the catchment lake area and the water quality sampling locations.
The first important item in this field work was to have a complete hydrographic survey of the lake
water body, in order to have a bathymetry map of the lake. This hydrographic survey was conducted
using field GPS-Eco-sounder survey equipment. Another important item in this field work was
measuring water levels at different locations within the catchment and the lake area and for this the
total station survey and levelling was required. Collection of water samples at several locations along
Edko main drain, at pumping stations and inside the lake for physicochemical and biological analysis
was a main target for preliminary assessment of water quality conditions. A total number of 19
samples were taken, ten samples out of this set were also taken for analysis of CHL-a. In addition, a
number of four soil samples were collected from the lake bottom for general interpretation of the soil
type and concentrations of chemicals and trace metals within the sediments. Knowing the importance
of the effect of submerged vegetation a sample from Potamogeton pectinatis was taken from the lake
for lab analysis of the chemical constituents in the plant tissues. Two velocity cross sections were
measured at the exit of the drain to the lake and at the exit of the lake to the sea channel.
Water quality samples were collected preserved and sent forms the sampling location at Edko Lake to
the Central laboratories for Environmental Quality Monitoring (CLEQM) at Delta barrages for
physicochemical and biological analysis. The CHL-a samples were collected and sent directly for
analysis to the Central Laboratories of the National Institute of Oceanography & Fisheries (NIOF) in
Alexandria. The results of water quality analysis from filed data collection for some of the basic
parameters are shown in table (5-5) .
Figure (5-15): Field work (1) sampling sites location within lake.