Daskalakis NikolaosPaschalakis Pantelis

Water supplyWater supply in Greece is considered as a Public Service

Greece is divided in 14 regionsEach region has its department for potable water preparation

Municipalities are rsponsible for the water supply and sewage services

EYDAP and EYATH In Athens and Thessaloniki the water supply need and

sewage services are covered by two big water companies

EYDAP and EYATH.

These two companies cover the water need of 5.8 million people (60% of Greek population)

In 2001 they entered the Greek Stock Market51% of the shares belong to the stateThey are funded for their projects 100% by

the Greek governmentThey propose monthly charges at the

begining of the year that are being approved by the Ministry Environment

Local water companiesCities with population less than 10000

peoplehave their own water companies They are controlled by the municipalities35% of budget is coming from the state75% of budget by local chargesTheir monthly charges are approved by

the local councilThey try to expand their services in

neighboring countries

Aspropirgos of Attica

Menidi Attica

Psitalia Piraeus

Neo Galatsi Attica

Problems that face water companiesIncreased water consumption during summer in Greek islands because of tourist influx and high temperature

Sea intrusion in the groundwater at the coastal regions

Reduction of annual rate of rainfalls

Answer to these problemsTo face these problems water companiesUse modern systems and equipment

and replace the old pipes to control the leakages

Use desalination systemsStore rainwater with surface reservoirsTransfer water by boats Water from the last three solutions is

used only for domestic use

Quality responsibility The authorities treat the water properly and use disinfection methods to assure the quality of water.the water quality is carefully controlled by

Companies laboratoriesUniversitiesCentral Laboratory of the State

Physical WaterPhysical water contains a variaty of inorganic, organic compounds and microorganisms. Organic compoundsDetergentsVOC’sPSB’s PAHspesticides

Inorganic compoundsCa2+ CO3

2-

Mg2+ Cl-

Na SO4-

K+ NO3-

Fe2+ PO4-

Mn2+ F-

Problems that are caused by these compoundsInorganic compoundsbad tastesalty tastebad smellillnesses in childrendiariamalfunction of kidneys and livercorrosion of supply tubes and pipes

Organic compounds Cancer Malfunction of kidneys Ravage of liver Ravage of blood transfer system Creation of tumors in brain Malfunction of neuric system

Microorganisms in waterbacteriavirusesalgemycetesprotozoaworms

Health problems caused by microorgansms in watercholera diaria typhus pneumonia meningitis hepatitis giardiasis malfunction of guts

Steps that take place to produce potable waterScreen filter in the entrance for the overflown solid

mattersScreen filter for alges and planktonAeration system for the divestment and oxidation of

flying microorganisms that cause bad smell and tasteFast mixture for uniform distribution of chemical

compounds and gasses in waterozone and chlorine is added in water to retard the

growth of microorganisms and oxidize the matters that cause bad smell and taste

flocculation that causes destabilization of colloids and creation of small flocks

small flocks unite to bigger flocksSedimentation takes place in the sedimentation

tank between the flying matters and the flocks that were created

absorption in active carbon occurs for the removal of matters that cause but taste and smell in water and also give color.

active alumina is used to remove F, P, Ar and Se through absorption

Oxidizing chemicals are used to destroy pathogenic microorganisms

sand is used for the absorption of solid matterschemicals are added to create sediment. During this

step Mg, Fe, heavy metals and hardness are also removed from water

lime-soda ash is added to the water to remove also hardness

  CO2 is added in water and reduce pH to restore chemical balance

NaF is added to water to control conciseness of Fr in water and to reduce the threat of teeth problems

microorganisms are added in water to exalt nitricion exchange, osmosis and evaporation to remove

the dissolved matters form potable water take place

eclectic removal of cat ions and anions from

water semipenetratable membranes are used to

withhold salts and attributes to clean water it is used electric potential for the filtering of

water via semipenetratable membrane that withholds salts

evaporation of multiple stages with condensation is used for the production of big quantities of desalted water, at the last step

Quality control in chemical laboratoriesWater is supplied to the public