#Feature

Environment : Our coastline is fragile and sensitive to sand mining

Sep 7, 2022, 3:02 PM | Article By: Edi Njie

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 and Duvivier - to help us with the problem of our coastline which was eroding badly due to the sand mining activities at Mile 5, (mile zero 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 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.  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 had been carried out prior to such action being taken.  

Subsequent to this, Haskoning and GAMECS carried out another study in the year 2000 (referred to earlier by my friend and brother Ebou Manneh) 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 /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 familiarize 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

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.  Some of the members of this Group 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:

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.

What is the situation regarding water supply pipes?

Rehabilitate the surface water drains including canals.

Rehabilitate the pumping station and pumps.

Pave the roads.  

It is clear that items 1–4 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 whom 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!

Abdoulie Touray raised the matter of the flooding at the ferry terminal followed by Mr. Jow’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 this forum 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 criticize 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. 

To Adelaide my sister, friend and “Doctor”:  I hope that I will soon have the opportunity to tour Banjul with you and then walk along the road leading to Serekunda and beyond.  I am sure that we will have a lot to talk about.

 

Autobiography

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 that Royal Victoria Hospital at the time, but by the Grace of Allah he became the first 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 McCarthy Square south after which I proceeded to the Methodist Boys High School (1950 – 1955) 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.  I spent seven years of my training on Banjul Streets except for the occasional visit to the provinces.  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 post graduate 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)

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 etc.  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.