Rasha Mohamed Mahmoud

By

Supervised by

Prof. Dr. Aziz M. Higazy

Drinking water

Microbiology of Water and Wastewater(AMP 616) 1st semester2014 - 2015

Drinking water

1. SOURCE OF DRINKING WATER

2. TYPES OF DRINKING WATR

• 97% of the water on the Earth is salt water. However, only 3% percent is fresh water; slightly over 2/3 of this is frozen in glaciers and polar ice caps.

• The remaining unfrozen freshwater is found mainly as groundwater, with only a small fraction present above ground or in the air.

• Fresh water is a renewable resource

About Water

Here also you could see that the total volume in the hydrosphere of water is

1.386 km2 (100%)

Distribute of water on Earth

SOURCE OF DRINKING WATER

1. Surface water

5. Desalination

4. Rain water3. Ground water

2. Frozen water

Surface water:Surface water is water in a river, lake or fresh

water wetland. Surface water is naturally replenished by precipitation and naturally lost through discharge to the oceans, evaporation,

and sub-surface seepage

Sub-surface water, or groundwater, is fresh water located in the pore space of soil and rocks. It is also water that is flowing within aquifers below the water table

Ground Water:

. Sometimes it is useful to make a distinction between sub-surface water that is closely associated with surface water and deep sub-surface water in an aquifer (sometimes called "fossil

water").

• Desalination:

Desalination is an artificial process by which saline water (generally sea water) is converted to fresh water. The most common desalination processes are distillation and reverse osmosis. Desalination is currently expensive compared to most alternative sources of water, and only a very small fraction of total human use is satisfied by desalination. It is only economically practical for high-valued uses (such as household and industrial uses) in arid areas. The most extensive use is in the Persian Gulf.

Frozen Water:Several schemes have been proposed to make use of icebergs as a water source, however to date this has only been done for novelty purposes. Glacier runoff is considered to be surface water.

Rain water

TYPES OF DRINKING WATR

TAP WATER

tap water is generally safe to drink, but it may be heavily filtered and treated with chemicals to reduce the presence of parasites. Tap water may contain heavy chlorine levels to help maintain micro-biological safety during storage, and transit, through water mains, tanks and pipes

The majority of tap water will have been used in some capacity before, so it is recycled, re-treated and re-filtered before consumption. Consequently, tap water can taste unpleasant and some customers worry about treatment by-products. The presence of parasites such as cryptosporidium is not unknown in tap water, which results in a number of requests to ‘boil water’ each year. Cryptosporidium, a bug found in surface water sources such as those taken from rivers and stream-fed reservoirs, can occasionally get through filters and isn’t removed by chlorine.

FILTERED WATERThere are a number of filtration and bottle filling

systems available today. The filtered water you drink is typically tap water that has been filtered to remove the chlorine residue – simply to improve the taste. Many of the filters used do not protect against contaminants such as the parasites Cryptosporidium and Giardia

Absolute 1 micron filtration removes any particles that are larger than 1 micron in size. This filtration leaves minerals in water. Ozonation is used by bottled water companies instead of chlorine to eliminate baceria. Ozonation does not change the mineral content of your water

• These types of water can originate from a mixture of sources; some of the well packaged and marketed bottled waters are merely re-processed tap water. Waters labelled as ‘purified’ or ‘vapour distilled’ are actually tap water that has gone through further processing, such as reverse osmosis, to make them suitable for sale as bottled drinking water.

• This process will remove most of the mineral content, notably calcium. So much so that in the UK the addition of calcium back to the water is compulsory, on the advice of the medical authorities, due to concerns over heart disease. Many of these waters are ozonated, which can result in harmful by-products like bromates. These waters are not renowned for their sensory stimulation qualities. Interestingly, these waters can appear under one brand name, but can be mutli-sourced in different countries from across the world

BOTTLED DRINKING WATER

SPRING WATERLike natural mineral water, waters that are labelled ‘spring water’ must originate from an officially recognised source. However, unlike natural mineral water they do not undergo the intensive 2 year recognition and regulatory process, and until recently did not have to be bottled at source.

Spring water is microbiologically wholesome, naturally free from pollution and harmful organisms but may use micro-filtration and UV treatments. It does not need to demonstrate a stable composition, and in essence is judged on the day it is bottled, which means that the composition can change.

Natural Mineral Water

• Natural mineral water must originate from an officially recognised single source and must be bottled at that location. Before water can be officially recognised as natural mineral water, it must be demonstrated to the UK authorities, through regular and frequent micro-biological testing for 2 years, that the source is protected from all risk of pollution and that the composition, temperature and other essential characteristics remain stable. The water is then subjected to ongoing statutory testing and continual maintenance for the duration of its continued extraction from its source

Comparison Chart

http://bodyecology.com/articles/best_water_to_drink.php#.VIGYt13q7IWhttp://www.hildon.com/our-water/what-is-natural-mineral-water/different-types-of-water/Water resources pptNSF/ANSI (2011). Standard 53: Drinking water treatment units--

health effects. NSF International and American National Standards Institute.(pdf)

References