Raissa Malu

Kinshasa, the blue gold rush!

In this time of containment due to the COVID-19 pandemic, we have time to think about our world and our practices. The one that is currently in my mind is our water management, the blue gold.

To limit the spread of the now famous coronavirus SARS-CoV-2 (for Severe Acute Respiratory Syndrome CoronaVirus 2), healthcare authorities require us to comply with strict hygiene measures. In particular, we must wash our hands often, for at least 20 seconds and with soap.

In Kinshasa, this has become a challenge. Whether you live in a posh part of the capital such as Gombe or Ngaliema, or a popular part such as Ngaba or Masina, you lack water (and electricity). The national company REGIDESO (and the SNEL for electricity) which has to provide this service to the Congolese population is outdated (to put it like that).

The origin of water

It seemed to me that it was the right time to be interested into water. Where does it come from? How is it processed? Are we right to dig boreholes all over the place to compensate for the failure of REGIDESO? Is it sustainable to pump water from the water table? Let's look at this together.

A few figures. Every minute, in the world 5 people die because they do not have access to drinking water. Polluted water and the environments it makes unhealthy kill 2.6 million people every year, 90% of whom are under the age of 14. (Source: National Geographic)

Insufficient improvement

However, the situation has improved overall. Between 2000 and 2015, the access to water of 1.6 billion people worldwide had improved, and 1.2 billion have been connected to drinking water. However, 11% of the world's population still do not have access to safe drinking water. Climate change is not helpful for all these efforts and 4 billion people will suffer from water scarcity by 2025. (Source: National Geographic)

It is in this context that on 28th July 2010, the UN General Assembly adopted a resolution making drinking water an inalienable human right: "The right to water guarantees that every human being has access to affordable, safe, sufficient, acceptable, accessible and suitable quality water for personal and domestic uses."

So let us start at the beginning and ask where does come from the water that we drink, that falls from the sky, that flows in our rivers and streams and comes out of our wells? I invite you to watch the following video on "The Water Cycle".

An invariable quantity

Our planet Earth contains a total volume of water of 1.4 billion cubic kilometers (1 cubic meter of water represents 1,000 liters). This amount of water has remained the same since its appearance on Earth ("nothing is lost, nothing is created, but everything is transformed" 😉).

These 1.4 billion cubic kilometers are made up of about 97% salt water and 3% fresh water. They form the hydrosphere, which is the Earth's total water supply. (We'll all sleep less ignorant tonight 😊)

Water in every layer

Salt water covers 2/3 of the Earth's surface and is found in the seas, oceans and ice floes. Freshwater (the one we are interested in, because our life and survival against coronavirus depends on it!) comes essentially from precipitation: 76% is trapped in glaciers; 22.5% is underground in the water tables, deep and captive water tables; 1.26% is on land: surface water (lakes, rivers, ponds, etc.); and 0.04% is in the air: clouds, rain, fog, mist. (Source: www.cieau.com)

Let's take an interest in the groundwater that in Kinshasa we seem to be determined to consume (fault to REGIDESO 😉). Let's watch the following video "Groundwater - An Introduction" produced by the Quebec Groundwater Network (I decided to involve the whole Earth for this post 😊). It is longer, 7 minutes, but please watch it to the end.

Groundwater is exhaustible

A water table is a body of groundwater stored at shallow depths in porous rock; it is usually accessible through a well or borehole.

When the cost of pumping and processing surface water is high, it is cheaper and more practical to pump groundwater. But, be careful. When the rate of groundwater refill is lower than that of pumping, the groundwater level drops.

That's right! Let's just remember this and spare you the mathematics needed to calculate the "water balance", which aims to establish the relationship between water inflows and outflows of a defined hydrological unit over a given period of time.

A four-stages process

The water that comes out of our taps must be processed to make it drinkable. Water treatment is generally done in four stages: screening and sieving which removes large particles; coagulation - flocculation - decantation which is the formation of cohesive, bulky and heavy flocs that are easy to decant; filtration where the very small particles present in the water are stopped by the sand; and sanitization with a small amount of chlorine, ozone or ultraviolet light. It is during this fourth step that pathogenic bacteria and viruses that remain in the water are eliminated (this step is of particular interest to us at the moment, isn't it?!).

A quarter of the population has access to drinking water

So, what is the situation in the Democratic Republic of Congo? With a low level of industrialisation and a small-scale agricultural sector that mainly uses rainwater, freshwater withdrawals are mainly for domestic use (52%).

However, in a 2011 report by the United Nations Environment Programme, Water Issues in the Democratic Republic of Congo: Challenges and Opportunities, we read that only 26% of the Congolese population has access to safe drinking water, an estimate well below the 60% average for sub-Saharan Africa as a whole. Despite the abundance of surface water, the vast majority of the Congolese population depends on groundwater and springs for drinking water.

The Congolese groundwater is being drained.

It is estimated that groundwater accounts for almost 47% (421 cubic kilometers per year) of the DRC's renewable water resources. The Congo Basin aquifer is one of the 37 largest aquifers in the world. However, it is said to have exceeded its sustainability threshold and is in depletion.

In other words, it will be a disaster in the years to come if we do not adopt responsible management of this resource now! Let's think about our children, our grandchildren, the next generations (or the next pandemic, you never know).

The necessary use of surface water

Aware of the situation (I imagine), the Congolese legislator promulgated Law No. 15/026 of 31 December 2015 on water (no one is supposed to be unaware of the Law, but it must be said that these legal documents are not the most pleasant to read. Finally, when you have to, you have to).

I would thus like to end with an appeal. Please, dear services of REGIDESO, dear Government, do what is necessary to offer to the users of the city of Kinshasa and other cities of the Democratic Republic of Congo, an access to drinking water from surface waters. It is unsustainable that we all dig boreholes (and it is not just a question of money) to satisfy our domestic needs (even if they remain much lower than those of the so-called industrialized countries).

A list of experts

We're in lockdown, so you've got time to look into it. I therefore invite you to contact (at a distance 😉) the many Congolese specialists on the subject, including Professor Céline Sikulisimwa, specialized in water science and technology, Faculty of Sciences, University of Kinshasa; Professor Raphaël Tshimanga, expert in hydrology and water resources for the Congo River Basin, Faculty of Sciences, University of Kinshasa; Professor Vincent Lukanda, Director of the Regional Centre for Nuclear Studies of Kinshasa and General Commissioner for Atomic Energy, Faculty of Sciences, University of Kinshasa.

They all participated in one or more editions of the Science and Technology Week 😊.

PS: Let's limit the spread of the virus at all costs, avoid contacts, stay confined! #StopCoronavirus

Science is (still) fun, join us !

 This post has first been published on LinkedIn. It has been translated in English by Afriscitech.

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