Let’s contain water pollution

These substances are referred to as pollutants and are usually components of either the following:
1. Raw sewage coming from blocked/burst municipal sewer lines or non-functional municipal sewer treatment facilities.
2. Untreated industrial waste (effluent) discharged directly into the environment.
3. Unsafe handling, transportation, storage, use and disposal of chemicals or hazardous substances.
4. Poor’s farming practices that may see the introduction of pesticides, herbicides and fertilisers finding their way into water bodies.
5. Poor land use which results in soil erosion.

This article focuses on water pollution, the possible source of water pollution and regulations associated with water pollution to ensure that water quality is maintained.

Regulations associated with water quality
The Environmental Management Act Chapter 20:27 and Statutory Instrument 6 of 2007 are used by the Environmental Management Agency to advocate for the application of the “Polluter Pays” principle in its entirety.

This including a fee for managing discharge licences and environmental charges based on volume and quality of effluent, as well as a penalty for any offences.
Therefore, local authorities operating a sewerage system or owner or operator of any trade or industrial undertaking is required to obtain a licence from the Environmental Management Agency to discharge any effluents or other pollutants into the environment.

The effluent is divided into four categories denoting risk as safe, low hazard, medium hazard and high hazard (Government of Zimbabwe, 2007).
The scale of the charges for the licence are related to the quality and quantity of the effluent, the poorer the management or quality of the effluent, the higher the charge.

In addition, the polluter pays for the policing of the regulations and for the monitoring of the effluent. Penalties for polluting that were moderately punitive under the Water Act, 1998 (imprisonment for a period not exceeding one year or/and a fine) are even more punitive under the Environmental Management Act (CAP 20:27) of 2002 (imprisonment not exceeding five years or/and a fine).

The polluter also remedies damage caused either to the environment or to a third party.
In practice, although this command and control approach is in force, the Water Quality Section is using a co-operative rather than confrontational approach, with fines being used as a last resort.

What are the sources of water pollution?
The presence of pollutants in water is primarily perpetrated by human activities. The sources of water pollution can be categorised as point or non-point sources.
Point sources of pollution are those where the polluting substances are emitted from an identified source directly into the waterway.

A pipe pouring toxic chemicals directly into a river is an example. Non-point sources are a result of diffuse percolation of pollutants from a large area into a waterway, for instance, pollutants from agricultural activities such as fertilisers and pesticides, leachate from landfills, soil particles from erosion as well as storm water runoff.

These pollutants are carried into streams and rivers by surface runoff, leading to serious deterioration of water quality.
This also affects aquatic and other organisms that may drink or be in contact with the water.
What are the types of water pollution?

Organic matter: organic pollution occurs when excess of organic matter, such as manure or sewage, enters the water. When organic matter increases in a pond, the number of decomposers will increase. These decomposers grow rapidly and use a great deal of oxygen during their growth. This leads to a depletion of oxygen and the decomposition process occurs. A lack of oxygen can kill aquatic organisms. As the aquatic die, they are broken down by decomposers which lead to further depletion of the oxygen levels.

Toxic Substance: A toxic substance is a chemical pollutant that is not a naturally occurring substance in aquatic ecosystems. The greatest contributors to toxic pollution are herbicides, pesticides and industrial compounds.

Thermal Pollution: occurs when water is used as a coolant near a power or industrial plant and then is returned to the aquatic environment at a higher temperature than it was originally. Thermal pollution can led to a decrease in the dissolved oxygen level in the water while also increasing the biological demand of aquatic organisms for oxygen.

Ecological Pollution: takes place when chemical pollution, organic pollution or thermal pollution are caused by nature rather than by human activity. For example, when a large animal, such as a deer drowns in a flood then a large amount of organic material is added to the water as a result.

How is water quality monitored?
The Water Quality Unit under the Environmental Protection (EP) Department has inspectors responsible for ambient monitoring.
This helps to identify and trace point and non-point sources of water pollutants.

Each month samples are collected from the identified sampling points (ambient monitoring points) and taken to the Environmental Management Agency Laboratory (EMAL), where an analytical report is produced.

Every citizen of this country is encouraged to take samples of water to this place through any of the nearest EMA offices if you suspect of, any pollutants from any water bodies in our country.

The majority of the point sources encompass manufacturing industries, mining and agriculture. Main sources of water pollution are found in urban areas evidenced by the presence of heavy sewage from homes and industries.
A major sign of water pollution in water bodies in major towns and cities in this country is the presence of water hyacinth.