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City of Banjul
Sunday, June 23, 2024

Banjul floods, understanding the genesis of the city’s eternal defence against water

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By Edi Njie

My name is Edi Njie. I was born in Georgetown but bred in Banjul. I was raised by my uncle Mr Farimang Singhateh who was a dresser-dispenser at the then Royal Victoria Hospital and became the governor general of The Gambia after independence.

I attended Albion School which was situated on a piece of land bounded by Grant Street, Albion Place, Allen Street and Lancaster Place. This is where the Nawec tanks now stand. My primary school was St Mary’s School (1946 to 1949) situated at the junction of Leman Street and MacCarthy Square south after which I proceeded to the Methodist Boys High School (1950 – 1955) then situated next to the Gamtel headquarters building on Dobson Street.

On passing the University of Cambridge School Certificate Examination in 1955, I joined the then Public Works Department as a technical trainee in civil engineering in January 1956 and spent seven years of my training on Banjul streets except for the occasional visit to the provinces.

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The next stage of my training was a seven-year (1962 –1969) period of study in the UK with the award of the Diploma in Civil Engineering (Dip CE) at Enfield College of Technology in 1967. This award was followed by a postgraduate course in Soil Mechanics and Foundation Engineering at London’s Imperial College which led to the award of the Diploma of the Membership of the Imperial College (DIC) in 1969 after which I returned to my activities on Banjul streets and the rest of The Gambia until my promotion in 1978 to the position of Director, Department of Hydro-Meteorological Services which later became the Department of Water Resources, from where I retired voluntarily in 1983.

My training and experience gained me the following:

Member of the Institution of Civil Engineers/Chartered Engineer – C Eng, MICE (1971)

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Member of the Institution of Water Engineers and Scientists – MIWES (1985);

Fellow of the Institution of Civil Engineers – FICE (1990);

Member of the American Society of Civil Engineers –MASCE (2000)

On the establishment of the Gambia Engineering Consultancy Services (Gamecs) in 1984, I continued to be involved in various aspects of the development of The Gambia including Banjul, such as the Banjul Drainage and Sewerage Project, the Banjul Streets Rehabilitation Project, coastal protection works and so forth. The list is by no means exhaustive. The above-mentioned stipulations are merely to show that I have some knowledge of Banjul and its development.

My involvement with coastal protection works goes back to the early 1960s when the then colonial government hired the world famous coastal protection specialists, Lewis & Duvivier, to help us with the problem of our coastline which was eroding badly due to the sand mining activities at Mile 5, (Mile 0 was at the General Post Office on Wellington Street and Mile 4 was at Denton Bridge). Our coastline is fragile and sensitive to sand mining. The reclamation works entailed the construction of groynes (low wall or sturdy barrier built out into the sea from a beach to check erosion and drifting) which are still visible on our foreshore. Our base camp was called “Little Northumbria” which was situated between the old Muslim Cemetery and Mrs Alice Carr’s property by Radio Syd. It appears that we are now repeating the same mistake by mining sand at Denton Bridge which is very close to Mile 5. It is hoped that adequate studies have been carried out prior to such action being taken.

Subsequent to this, Haskoning and Gamecs carried out another study in 2000 which was followed by reclamation works.

About three years ago, a prominent person in the civil service came to inform me that they wanted me to be involved in the planned development or rehabilitation of Banjul streets. I readily agreed on condition that they also agreed that my services were not to be paid for because I owe Banjul so very much.

After the first meeting which was informatory, I decided to tour Banjul streets on 6th October 2018 including the Bund Road and the pumping station on Bund Road which was completed and became operational in July 1952, in order to familiarise myself with the current state of affairs thereat. This was necessary because I live in Fajara and work in Kanifing and I hardly had any cause to go to Banjul. At the next scheduled meeting, I rose to talk about the development of Banjul and to give advice on the sequence with which any works were to be carried out. However, my presentation was interrupted by tears streaming down my cheeks. It was Mr Fatajo, the former managing director of Nawec who gave me his handkerchief to wipe my tears. Why did I cry? I cried because of what I saw. I observed that the very backbone of the drainage system of Banjul had been broken. I was soon excluded from attending further meetings and my involvement ended there and then.

It is widely reported that Banjul is one of the ten cities in the world which are sinking. It has been established since the colonial days that Banjul would be flooded if the following events occur simultaneously: the stage of the River Gambia rises to a certain level at Banjul, the occurrence of onshore winds and heavy rainfall.

The drainage system was designed to cater for these occurrences. The Bund Road pumping station had three heavy-duty pumps that were seldom put on at the same time. In most cases, the activation of one pump was able to cope with low intensity rainfall and for most of the time the third pump was a standby pump. Banjulians may recall that the drainage was so efficient that during the dry season, the sluice gates used to be raised during high water to allow water to flow into the canals and drains of Banjul, taking along small fishes which used to thrill children.

Having been involved in the construction of the Banjul Sewerage and Drainage Project and having put down well over one hundred boreholes for soil investigation in Banjul and with the knowledge of the soil variability in Banjul, there is now the likelihood of the displacement of the pipes. I suggested that priority be given to finding out the present state of the system because any leakage would contaminate the ground water which would be a health hazard. I suggested that the sequence for the implementation of any work was to be as follows: 

1.         Determine the adequacy of the pipe sizes of the sewerage system. Are the designed sizes, lines and grades still applicable since these were based on studies several years ago?

2.         What is the situation regarding water supply pipes?

3.         Rehabilitate the surface water drains including canals.

4.         Rehabilitate the pumping station and pumps and pave the roads.

It is clear that items 1 to 4 could be carried out simultaneously but any paving of the roads would have to wait for the completion of items 1, 2 and 3.

As a follow-up on the visit made in October 2018, I made another tour of some parts of Banjul including Bund Road pumping station on 9th August 2022 in order to see the present state of affairs. I was accompanied on this visit by some senior members of Gamecs, one of who was involved in the implementation of the Banjul Sewerage and Drainage works. It was observed that the backbone of the drainage system was still broken. It was also noticed that two pumps have been installed at the pumping station. Are these pumps appropriate and of adequate capacity? Can they be effective under the present condition when the gates are in a terrible state of disrepair and are lock jammed? I wonder!

A friend raised the matter of the flooding at the ferry terminal followed by another friend’s post showing the flooding on Bund Road on Saturday 13th August 2022. These were not unexpected. There could be other such recurrences in September.

The flooding on Bund Road occurs on a section of the road between Cotton Street and the pumping station. It is that section which is the lowest along the Bund and the most exposed part of the Bund. It has been the practice that it is raised every few years and to the best of my knowledge, any such serious action was made by Hurst Sommer’s Company called Luis Diaz, several years ago. The periodic raising of the road and stone pitching of the sides is necessary in order to prevent over topping of the road. Something even more serious than what we saw a few days ago can occur when we have spring tides higher than what we had.

In answer to a question posed by a member of the public as to whether we have hydrologists in this country, the answer is yes, we have.

Finally, I want to make apologies to anybody on whose toes I may have trodden. This little contribution is not intended to show off or to seek attention or recognition or to criticise anyone. It is merely a small contribution for the information of the thousands of people who are interested in the development of Banjul and to suggest that the development of Banjul should be carried out holistically. The matter of coastal erosion should always be seriously considered.

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