Water Resources Management in the region of Orestiada Quality of Surface Water Arvaniti Eleni Kakos Stelios Papantoniou Manolis Paraskevopoulou Magda

The region of Orestiada r. Evros r. Ardas r. Erithropotamos

r. Ardas

Chemical Analyses Chemical analyses are conducted by the Institute of Geological Researches as concerned the physical – chemical parameters, the ions and some elements in very small quantities. Samples are taken from the rivers Evros and Ardas.

Code NumberPlaceUse ΡΑ1 (r. Ardas)KastaniesIrrigation ΡΑ2 (r. Ardas)RiziaNone ΡΑ3 (r. Ardas)EleaNone ΡΑ4 (r. Ardas)KomaraNone ΡΑ5 (r. Ardas)Ardas DamIrrigation ΡΕ1 (r. Evros)OrmenioNone ΡΕ2 (r. Evros)MarasiaNone ΡΕ3 (r. Evros)VissaIrrigation Places of Sampling

PA1 PA2 PA3 PA4 PA5 PE1 PE2 PE3

Physical – Chemical Parameters TemperaturepHConductivityHardnessAlkaline Units °C - μS/cm (20°C) mg/l CaCO 3 mg/l CaCO 3 Maximum Limits ΡΑ1 (r. Ardas)21,08, ,043,0 ΡΑ2 (r. Ardas)21,08, ,061,0 ΡΑ3 (r. Ardas)20,08, ,052,0 ΡΑ4 (r. Ardas)20,08, ,037,0 ΡΑ5 (r. Ardas)19,58, ,2119,0 ΡΕ1 (r. Evros)20,010, ,8 - ΡΕ2 (r. Evros)20,09, ,99,0 ΡΕ3 (r. Evros)20,08, ,851,0 MIN19,58,1180,070,09,0 MAX21,010,0523,0200,2119,0 AVERAGE20,28,9345,5122,553,1

Ions + ions- ions Ca +2 Mg +2 Na + K+K+ NH 4 + HCO 3 - Cl - SO 4 -2 NO 3 - NO 2 - Units mg/l Maximum Limits , ,1 ΡΑ1 (r. Ardas)26,58,817,04,00,0952,517,761,42,20,00 ΡΑ2 (r. Ardas)25,76,815,04,00,0874,414,251,61,80,00 ΡΑ3 (r. Ardas)26,57,314,04,00,1063,417,751,70,90,00 ΡΑ4 (r. Ardas)18,45,810,03,00,1045,110,642,11,30,00 ΡΑ5 (r. Ardas)64,19,714,03,00,04145,210,680,07,90,18 ΡΕ1 (r. Evros)25,719,040,06,00,21<024,880,02,20,04 ΡΕ2 (r. Evros)28,115,140,06,00,2111,031,980,04,00,01 ΡΕ3 (r. Evros)27,319,019,040,06,00,2162,242,580,00,90,01 MIN18,45,810,03,00,011,010,642,10,90,0 MAX64,119,040,06,00,2145,242,580,07,90,2 AVERAGE30,311,423,84,50,164,821,365,92,60,0

Elements in small quantities FeZnCuMnPbCdF-F- AlNiAsCrBBr - Units μg/l Maximum Limits ΡΑ1 (r. Ardas) < ΡΑ2 (r. Ardas) < ΡΑ3 (r. Ardas) < ΡΑ4 (r. Ardas) ΡΑ5 (r. Ardas) ΡΕ1 (r. Evros) ΡΕ2 (r. Evros) ΡΕ3 (r. Evros) MIN MAX AVERAGE

Sodium Adsorption Relation (SAR) and Alkaline Index (% Na) indicate the suitability of water for irrigation. SAR<6 or Alkaline Index<20 means that the quality of water for irrigation is excellent. SAR and Alkaline Index

SARALKALINE INDEX ΡΑ1 (r. Ardas)0,7329,22 ΡΑ2 (r. Ardas)0,6829,10 ΡΑ3 (r. Ardas)0,6227,04 ΡΑ4 (r. Ardas)0,5226,77 ΡΑ5 (r. Ardas)0,4314,64 ΡΕ1 (r. Evros)1,4640,02 ΡΕ2 (r. Evros)1,5141,78 ΡΕ3 (r. Evros)1,4439,35 MIN0,414,6 MAX1,541,8 AVERAGE0,931,0

Water Distribution 53 % of water for irrigation comes from surface water 47 % of water for irrigation comes from water drills

Waste Water Treatment There is a unit of waste water treatment in Orestiada that accepts m 3 /day of waste water. Having been treated, they are discharged in a canal which finally ends in r. Evros.

Waste Water Parameters Physical–Chemical ParametersInletOutlet pH7,597,78 Θ (  C) 15,4816,52 BOD (mg/l)314,005,50 COD (mg/l)567,0031,00 N-NH 4 (mg/l)61,000,30 P-PO 4 (mg/l)24,330,52

Conclusions The water of r. Evros in contrast with this of r. Ardas is overloaded with SO 4 -2 as it comes into Greece. This may happen because Bulgarian plants throw their waste in r. Evros. Afterwards, the concentration of SO 4 -2 is getting lower because of its mixing with r. Ardas, r. Erithropotamos and Turkish r. Tountzas.

Conclusions SAR is lower than 6 in all the samples and Alkaline Index varies between 20 and 40. This means that the quality of surface water in the region of Orestiada is very good and the water is suitable for irrigation.

Repeated chemical analyses are necessary because there are suspicions that Bulgarian plants pollute r. Evros with radio – active waste which finally end in Thracian Sea (North Aegean Sea). The values of parameters for the treated waste water show that their discharge in the r. Evros does not create any problem. Conclusions