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Reviving dying waterbodies in the light of rising pollution levels, population growth

Ankobra River Ankobra River

Tue, 27 Jun 2017 Source: Alexander Anim-Mensah

It was astonishing and even scary to observe on a recent visit to Ghana that several waterbodies have disappeared and some are on the verge of extinction.

Majority appeared laden with pollutants while some sizable rivers were now reduced to narrow streams (creeks). Other major rivers flowed with a constant coffee brown coloration, as if there had been a never ending heavy rainfall.

Some rivers significantly silted, leaving pockets of ponds on the beds, while others flowed “black” signifying no life.

Water as known to everyone plays a vital role in our existence as humans or living things in general. Due its essential nature, there is nothing like over dependence on this nonrenewable resource. Consequently, it is said that “water is life”, without it, life would cease.

After a cursory investigation, the following were observations I gathered as some of the possible causes of the disappearance of waterbodies and the sources of pollution in Ghana;

• Accepted norms of recovering pieces of lands for industrial, commercial and domestic activities fully or partially block water bodies in some areas.

• Dumping of refuse into waterbodies is a common practice in some areas. In fact, several places have refuse dumping grounds located close to waterbodies. This results in conscious and unconscious dumping of waste into such waterbodies.

• Some industrial effluents laden with pollutants are allowed to flow into waterbodies.

• Heavy defecation along waterbodies is part of the norm in many areas. • Destruction of watershed protection; something that most inhabitants are unaware of within the catchment of the watersheds.

• Stripping off vegetation/materials of mountains for economic activities. These vegetation are necessary to trap and assist in seepage of rainwater back to feed ground and surface waters to promote the “hydrological cycle”.

• Lack of planning and unregulated siting of domestic, commercial and industrial construction activities impacting heavily some waterbodies

• Inappropriate disposal of domestic, commercial and industrial wastes especially chemicals and/or drugs that find their ways into the various waterbodies.

• Run off from farmlands containing chemicals including pesticides, weedicide and fertilizers.

• Run-offs carrying spills from various petroleum products from the numerous gas (“petrol”) stations around the nation.

• Improper disposal and handling of used engine oils from the various workshops finding its way into our waterbodies.

• The abnormal rise in illegal mining “galamsey” in the countryside sending high levels of toxic pollutants into ground and surface water systems.

I used to work at the Environmental Department at Tema Oil Refinery-Tema, and also served as a volunteer at the Environmental Protection Agency – Sekondi office. As a result, I have significant experience and insight in water and wastewater treatment as well as waste treatment and management. The possible negative impact of the aforementioned observations, if not properly addressed, would begin to threaten our own existence. Note that, no one is immune since the system encircling the earth is connected. One man’s action, either positive or negative is connected to the global community.

Given this high pollution levels and the dying rate of waterbodies; amidst the souring population growth, and somewhat minimal environmental regulatory enforcement, the situation will only get worse. This means, we could be stabbing our own future if appropriate measures including sustainability are not addressed with the utmost urgency. Majority of us already know the potential threats posed by some of these pollutants could be physical, chemical, biological and a combinations. Pollutants irrespective of their sources have the potential to partition between water, soil, air, living and non-living things they contact.

I would highlights here, some information on some types of pollutants, their impacts, water quality parameters, and some remedial actions necessary to minimize their effects.

Given that these waterbodies are already polluted, the first step in dealing with the issue is to assess the extent of pollution and determine if a natural healing process after the pollution is eliminated is possible without significant impact and the need for external interventions. If this is not possible, a combination of remedial actions, elimination or reduction of the pollutants, treatment and sustainable methodologies will be required. In all cases, identifying the type of pollutants and the sources, and characterizing them is necessary to deploy the necessary treatment steps. By nature, these pollutants could be put into three (3) main categories namely; physical, biological, and chemical. However, each category could have an impact that span across all three (3) categories or combinations.

Physical categorization is simply what one observes by visual inspection of the polluted water. This includes color, turbidity, clearness, and presence of suspended materials or debris. These observations could have sources which are organic and/or inorganic in nature. The effect of this physical characteristics apart from its inherent effects, could show up to have chemical and/or biological impacts.

Biological categorization considerations include germs (“microbes”) present in the water, oxygen demand to breakdown any organic food material and/or chemicals, and pollutants’ bioaccumulation potential. This biological characteristic apart from its inherent effect, in addition, could also show up to have chemical and/or physical impacts.

Chemical categorization of water considers dissolved metal, non-metals and salts such as sodium, calcium, mercury, manganese, aluminum, chromium, nickel, magnesium, chloride, sulfate, silicates, etc. and gases from natural and/or artificial sources dissolved in water. The chemical characteristics apart from its inherent effects, furthermore, could show up to have physical and/or biological impacts.

The severity of these pollutants is dependent on the levels present. Some physical appearance of water may be due to biological and/or chemical reasons. Similarly some chemical characteristics are as results of physical and/or biological causes and some biological may be a result of chemical and/or physical causes.

It is worth to point out that all the three (3) pollutant categories i.e. physical, biological and chemical are in a balanced equilibrium state until changes including temperature, rainfall, etc. shifts the balance. Other dependencies include climatic conditions, rainfall pattern and geology of an area.

All these three (3) characteristics of water in equilibrium, is what defines overall water parameters such as total hardness, pH, total dissolved solids (TDS), alkalinity, conductivity, total suspended solid (TSS), etc.

Where organic waste pollutants such as food materials and faeces (feces) are in the water; oxygen and microbes may be required for breakdown if a physical separation is not appropriate. This often leads to depletion of oxygen in the water if there is no external intervention. As a result, this could stress aquatic life, as well as the water’s potential to recover.

Sources of oxygen in some waterbodies come from existing plants in the water and/or from the atmosphere. This means there could be sufficient or insufficient amount of oxygen to support breakdown and while leaving reasonable amount for aquatic life. The question is how do we quantify, monitor and provide the necessary interventions as well as provide treatments to protect our waterbodies from dying?

There are even more questions to be asked in situations where the pollutants are toxic chemicals coming from illegal mining (“galamsey”), and from inappropriate disposal of chemicals and/or drugs from domestic, commercial and industrial sources. How is the situation dealt with given that these pollutants are already present in water causing harm and threatening lives?

How can we draw an effective awareness on sustainability, enforcement of regulations, development of robust treatment and/or disposal processes? What about the effects of these new chemicals and increased suspended particles on the existing treatment system? Are the existing water treatment systems updated sufficiently to take up these new challenges, that is, to treat municipal water with these new pollutants to acceptable levels to safeguard lives? What new characterization, quantification and monitoring processes are in place to deal with the situation? How does the future look for these waterbodies and the living existence?

Since no one size fits all, it is important to assess each situation on case by case basis and deploy the necessary treatment processes to achieve the objectives. In as much as a water sample could be characterized by physical, chemical and biological parameters; so can the treatment processes involve a combination of biological, physical and chemicals methods.

Biological treatment process include bioremediation, this may involve the use of bacteria; chemical processes include use of flocculants/ coagulants, pH adjusters, etc. while physical processes may involve processes such as sedimentation, and filtration. In some situation, it is possible to use specialized or specific plants to extract pollutants from the soil and water i.e. “phytoremediation”.

In summing up, it is hopefully clear that pollution and its effects could span across water, soil and air. The impact could sometimes be much larger than anticipated. Therefore, programs deployed to address and resolve the existing water pollution issues should not only look at one side of the issue.

Currently, illegal mining “galamsey” is a major problem but, an overall picture is needed to determine the interconnectivity and overlaps so that formidable solutions can be developed without reinventing the wheels.

We should not lose sight of the fact that collective action includes awareness and education as a key part in dealing with such issues. This requires commitment from all aspects of society especially from the government, universities, industries, chiefs, and every individual. This may require huge financial commitment, resources, time, excellent planning and enforcing necessary codes and laws to name a few. This venture could be made attractive with a payback story and depends on the how the objectives are defined. This can be done. Let’s make the world a better place. God bless.

Columnist: Alexander Anim-Mensah