Insurmountable problems associated with elevated groundwater levels in coastal cities
Near surface groundwater levels causes considerable problems in coastal cities, sometime insurmountable. A typical of such cities is Abadan in southwest Iran, on the shores of the Persian Gulf. In Abadan, seawater seeps into city’s neighborhoods via subsurface pathways. Seepage areas turn into salt pans in summer season because of evaporative concentration. In addition, in areas where underground seawater level is close to the land surface, loose ground surface does not sufficiently support any form of civil construction; roads subside, buildings tilt and open holes develop into streets. In the other hand, elevated seawater level does not allow any surface water to percolate downward, neither does it allow any leaking sewerage to be absorbed by subsurface medium. As a consequence, surface run off fill up the streets in rainy days and leaking sewer emerges into land surface. Low topographic gradient exacerbate and complicate all these issues. It slows down the movement of urban runoff into Persian Gulf. As a Professor of Groundwater hydrology who lives in Abadan, I would like to raise these issues at the 8th World Water Forum discussion and learn from the experience of the other countries in tackling numerous water issues in coastal cities.
1 year 10 months
Thank you for your reply. It seems to me that you are facing mainly quality related problems in Brazil. Here in Abadan the problem stems from the high quantity of water, namely elevated groundwater levels as mentioned in my initial comment; but it then leads to quality issues. Specifically I am very keen to know about the ways to stop the seepage of seawater into urban areas through subsurface path. If we pump out the groundwater, which is actually intruded seawater, it is then replaced by incoming seawater. A solution may be to increase the elevation of the land surface by using materials such as sands and silt and piling/compacting them on the surface, something like “land reclamation”. If this is done, then the elevation of the lad surface will become higher than the sea level, and a topographic gradient is established from land surface toward the sea. Also, the surface water flow or urban runoff flows toward the sea.
1 year 9 months
Thank you for your comment. Of course integrating SDGs is a solution. However the lack of awarness among both government officials and public, the inadequaty of funds, the harshness of geological, topographical and hydrogeological settigs and transboudary issues (because the city I am taking about is located close to border) all complicate the solution and make it difficult. In a foreseable future I do not see much hope of alleviating the issue I raised, i.e. consequences of elevated groundwater level in coastal cities.
I have done some research on Temporal Changes in the Chemical Composition and Salinity of Wet atmospheric precipitation (Rain and snow) in a few cities in Iran. A gentle increase in the salinity of atmospheric precipitation has been observed, while at the same time, some decrease in the quantity of atmospheric precipitation has been recorded (for the years studied). It seems that increase in the salinity of atmospheric precipitation is due to a) decrease in quantity of precipitation and b) increase in aerosols and air pollution. I would like to hear from everyone who has an experience in this field. Particularly, I want to ask whether anybody knows of the ways to differentiate between the impacts of decrease in precipitation quantity and increase in air pollution (on the salinity of atmospheric precipitation). For instance, 20% of the increase in atmospheric precipitation salinity is due to decline in rainfall, and 80% is due to intensifying air pollution.
Thank you very much
Gholam Abbas KAZEMI
1 year 9 months
Thank you Arturo,
I look forward to hearing from you and your colleagues.
1 year 9 months
A while ago, I posted a comment regarding deterioration of the quality of atmospheric precipitation (snow, rain) and the experiences that you may have on this topic. Please share with me your ideas and findings on this issue. I think this is a considerable problem that is associated with climate change.
Thank you very much.
Gholam Abbas Kazemi
1 year 9 months
Thank you. The initial comment was posted on 4 or 5 January. I received a few comments afterwards. I am particulary interested to find out about the consequences of climate change on the quality (EC and pH and chemical composition) of snow and rain.