WATER POLLUTION CONTROL
Water pollution is the contamination of water bodies by substances that make the water
unusable for any human activities. Water is regarded as the universal solvent which has the
ability to dissolve more substances than any other liquid on earth and hence it is vulnerable
to any source of contamination.
Causes of water pollution
1. Agriculture is one of the biggest sources of water pollution. Every time it rains
fertilizers, pesticides and animal waste from livestock operations are washed away
straight into the water bodies such as dams, rivers, streams, lakes etc. Nutrient
pollution from nitrates and phosphates which plants and animals need to grow is
another major cause of water pollution resulting in heavy nutrient loading of our
fresh water sources. This eventually leads to algal blooms that then deplete the
oxygen reserves in our water bodies over time.
2. Mining is also another major contributing activity to water pollution. Water pollution
is primarily associated with mining operations as they threaten all kinds of
waterways from rivers and lakes to drinking water supplies. This kind of pollution
occurs when chemical agents such as sodium cyanide or sulphuric acid used by
mining companies to separate the target mineral from the ore spills, leaks or leaches
from the mine site into nearby water bodies. These chemicals are highly toxic to
humans and the wildlife.
3. Domestic/industrial effluent is another contributor to water pollution. Waste water
is considered as used water from our homes or industries. Most effluent flows back
into water bodies without being treated or having been partially treated. Burst pipes
from sewage lines are also a major contributor to water pollution. Storm water
runoff which occurs when rainfall carries road salts, oils and grease, chemicals and
debris from impermeable surfaces into water ways is another source of water
contamination.
4. Oil is also another biggest water polluter. Oil and gasoline that drips from millions of
cars and trucks every day is washed by rain to the water bodies where they cause
water pollution. Oils are dangerous contaminants as they negatively affect aquatic
life.
5. Solid waste pollution is damaging to the health of aquatic ecosystems and can harm
wildlife directly. Many solid wastes such as plastics and electronic waste break down
and leach harmful chemicals into the water making them a source of toxic or
hazardous waste. Of late we have witnessed high loads of micro plastics in our water
bodies, which are then ingested by humans through the food chain and direct
consumption of contaminated water. These plastics have been linked to various
health conditions that include cancers.
Effects of water pollution
On human health
Drinking water from contaminated water sources especially in rural areas where there is
untreated water poses very harmful to human health. For instance people get ill from these
waterborne pathogens and animal waste. They suffer from diseases like cholera, typhoid
and dysentery. These have the potential to disrupt the lives of whole communities. Also the
introduction of chemicals can lead to a reduction in the availability of palatable water thus
affecting water availability for domestic use.
On the environment
Healthy ecosystems rely on a complex web of animals, plants, bacteria and fungi in order to
thrive and the disruption of this co-existence is harmful to the environment. Chemicals and
heavy metals from industrial and municipal wastewater has the potential to disrupt
biodiversity hence reducing the productivity of the affected ecosystems.
What the law says about water pollution
The environmental Management Agency through the EM Act Cap (20:27) and its statutory
instruments monitors the disposal of wastes and waste oils into the environment. Under the
provisions of the EM Act no person shall dispose of waste or effluent into a public stream or
into any other surface water or ground water, whether directly or through drainage or
seepage, except under a license. The said discharges shall be in compliance to the disposal
standards contained in the statutory instrument 6 of 2007 and shall comply with the blue,
green, yellow and red bands of classification.
The EM Act also prohibits the disposal of solid waste at undesignated points and makes it an
offence to do such activity. The law then further directs all local authorities to designate
suitable sites as waste collection points. These points known as landfills shall be licenced
and shall have suitable lining material to prevent seepage or leaching of waste into
underground water. The Act also prohibits littering and makes it an offence to throw waste
at points not designated for such activity. It is encouraged that all waste find its way into a
waste receptacle prior to treatment and disposal.
For mining waste the EM Act Cap (20:27) makes it an offence to dispose of mining waste in a
manner that causes pollution and encourages the use of lined tailings impoundments.
Through the polluter pays principle the Agency then incentivises the construction of
environmentally friendly tailings impoundments.
Get in touch with us we are always ready to listen. Email: eep@ema.co.zw or visit our website
www.ema.co.zw. Toll free 08080028, sms/whatsapp 0779 569 707, Like our Facebook Page-
Environmental Management Agency or follow us on@EMAeep.
