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 + |
< 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 |
