Water Quality in the city of Chania - Water Quality Monitoring

The quality of potable water in Chania is exceptional. To ensure this quality is first priority for DEYACh and water quality monitoring according to the legislation is an essential element in order to achieve it.

In 2004 there were realised

  • 2495 samplings in the city network
  • 2815 laboratory analyses in water from the network
  • 105 samplings in water resources
  • 858 analyses in water from the resources
  • 2104 measurements of residual chlorine on the spot in the city water network

Since 2005 the process of water chlorination has become automatic with on-line measurements in 20 stations in the network which measure continuously the residual chlorine 24h a day. Measurements are recorded by the system of supervision and control of water supply network (SCADA)

The exceptional quality of water is presented in the following table compared to the being in effect Greek legislation that has been harmonised from 25-12-2003 with European directive 98/83

Parameter

Typical concentration in the network of water supply of DEYACh

Maximum concentration according to KYA Y2/2600/2001

     

PH

7.95-8.15

>6.5 και < 9,5

Temperature

14-18 °C

 

Conductivity

250-270 μS/cm

2500 μS/cm

Turbidity

0.5 NTU

Acceptable from the consumers and without any uncommon change

Nitrates

1.3-2.2 mg/l

50 mg/l

Nitrites

0.02 mg/l

0,5 mg/l

Ammonia

<0.05 mg/l

0,50 mg/l

Chlorides

10-12 mg/l

250 mg/l

Sulfates

14-18 mg/l

250 mg/l

Fluorides

0.2-0.5 mg/l

1,5 mg/l

Permaganate index

0-1 mg O2/l

5 mg/l

Calcium

38-43 mg/l

 

Magnesium

12-13 mg/l

 

Total hardness

145-160 mg CaCO3/l (8-9 Dh)

 

Temporary hardness

110-120 mg CaCO3/l

 

Permanent hardness

35-45 mg CaCO3/l

 

Alkalinity

110-120 mg/l

 

Bicarbonates

130-145 mg/l

 

Iron

10-20 μg/l

200 μg/l

Copper

3-15 μg/l

2000 μg/l

Manganese

<10 μg/l

50 μg/l

Boron

0.15 mg/l

1 mg/l

Sodium

7-8 mg/l

200 mg/l

Potassium

0.5-1 mg/l

12 mg/l

Arsenic

<1 μg/l

10 μg/l

Antimony

<1 μg/l

5 μg/l

Cadmium

<1 μg/l

5 μg/l

Lead

<1 μg/l

10 μg/l

Aluminum

2-7 μg/l

200 μg/l

Nickel

< 1μg/l

20 μg/l

Chromium

< 1 μg/l

50 μg/l

Mercury

< 0,4 μg/l

1 μg/l

Selenium

< 2 μg/l

10 μg/l

TOC

0.8 μg/l

without any uncommon change

PAH

<0.032 μg/l

0,1 μg/l

Benzo-a-pyrene

< 0.003 μg/l

0,01 μg/l

Pesticides

Non detected

0,1 μg/l

Total pesticides

Non detected

0,5 μg/l

Total trihalomethanes

<2 μg/l

100 μg/l

Trichloroethylene +
tetrachloroethylene

< 0,8

10 μg/l

1,2-dichloroethane

Non detected

3 μg/l

Bromides

< 2 μg/l

10 μg/l

Hydrogen sulfide

Non detected

Non detected organoleptically

Total dissolved solids

165 mg/l

1500 mg/l

MBAS

< 0.05 mg/l

0.2 mg/l

Phosphates P2O5

0.18 mg/l

5 mg/l

Residual chlorine

0.25-0.35 mg/l

Minimal concentration 0.2 mg/l

     

Total coliforms

0 colonies/ 100 ml

0 colonies / 100 ml

E.Coli

0 colonies / 100 ml

0 colonies / 100 ml

Enterococcus

0 colonies / 100 ml

0 colonies / 100 ml

Clostridium perfingens

0 colonies /100 ml

0 colonies /100 ml

Total bacteria 37°C

< 10 colonies /1 ml

without any uncommon change

Total bacteria 22°C

< 20 colonies /1 ml

without any uncommon change