الفهرس 
IntroductiionOnly 14 pages are availabe for public view
 |  | from | 215 |  |  |
| | | from | 215 | | |
Abstract
The New Damietta City is located at the northeast part of Nile Delta at Mediterranean Sea coast, limited by latitudes 31º 25′ and 31º 27′ N, and longitudes 31º 38′ and 31º 43′ E. The present study deals in the distribution of the different water resources of the New Damietta City. Sixty water samples for hydrochemical analysis. Evaluation of the collected water samples for different purposes was considered. The problem of waterlogging and salinity and their effects were discussed. At the end of the study, some recommendations to manage these problems are suggested. Surface lithology is dark grey loamy sand layer in all area except along the northern section. The texture of the samples differs from sandy to loam soil. Deterioration of soil in the studied area is directly related to increasing salinity and waterlogging. The geomorphologic units of the City divided into coastal flat, sabkha, wet land and urban area. The coastal flat includes shore and backshore area in addition to wide sand flat with nabkas fields. Sabkha shrubs were also observed throughout the backshore area. Wet lands are observed on a large scale with a characteristic surface layer of salt. Cultivated areas appear as discontinuous patches around administrative buildings and both sides of road. With regard to surface water samples, pH values are slightly alkaline. The salinity of the surface drainage samples is more than that of the irrigation system. The maximum salinity value of City drain was encountered opposite to the industrial area. Sodium shows a good correlation with bicarbonate in irrigation water and with chloride in drainage water. Concerning the groundwater of the shallow tubewell, pH values range from 7.02 to 7.67. The salinity indicates fresh to brackish water. The increase of salinity is conformable with concentration of chloride, sodium and sulfate ions. Pertaining to the chemical analyses of groundwater samples from boreholes, the average pH values is 7.23. Total dissolved salts content ranges from 20 g/l to 293 g/l; indicates hypersaline water. Chemical type is chloride-sodium due to dissolution and ion exchange processes. Higher values of magnesium reflect the effect of leaching of local evaporates. Sulfates represent the second anion and increase as salinity increases. The sodium imbalance refers to the prevalence of chloride over sodium which reflects the influence of sea water. The base exchange coefficient has positive values except two samples which reflect mixing with municipal water. The excess of sulfate is less than the unity reflecting low sulfate relative to chloride. High values of sulfate are an evidence of evaporation. The rate of evaporite dissolution is less than the unity which indicates that magnesium exceeds calcium due to marine origin. Municipal water is within the drinking safe limit while shallow tubewells samples have positive coliform group with unsuitable salinity and need desalinization processes. All irrigation canal samples can be used for livestock and poultry, shallow tubewell samples can be used for poultry and drains are unfit. All irrigation canals and most of the samples from shallow tubewell have permissible salinity for irrigation where drains vary from doubtful. The sodicity of irrigation canals and shallow tubewell samples refers to low sodium hazard and safe in irrigation uses. Meanwhile, drain samples are unsuitable. The exchangeable sodium percentages of irrigation canals samples are extremely sensitive. All drains and shallow tubewell samples vary from extremely sensitive to sensitive classes. Residual sodium carbonate of all samples is except two samples. All analyzed water samples have pH values are not aggressive to reinforced concrete except one groundwater sample from boreholes. Concerning magnesium concentration in borehole groundwater samples vary from strong aggressive to very strongly aggressive for reinforced concrete. Boreholes groundwater samples suffer from highly attack of sulfate salts and very strongly aggressive water for reinforced concrete. Chloride concentrations in the investigated groundwater borehole samples. Such high chloride concentrations lead to corrosion of steel in reinforced concrete. Chemical salt attack is caused by the ingressing salts especially sulfate and chloride salts into cementation material and loss of corrosion protection of the steel reinforcement. The New Damietta City is extensive waterlogged area due sea water intrusion, high watertable, excessive irrigation of gardens and rainfall partially in winter season. The depth to water ranges from 60 to 90 cm, which creates problems in the infrastructure. Anomalies are noticed in most industrial effluent such as colour, temperature, pH value, salinity and some heavy elements. Periodical observation of industrial waste water must be found to keep hygiene environment.