Reports on Environment and Urban Development for Alaverdy

GEO ALAVERDI: ENVIRONMENT AND URBAN DEVELOPMENT

Diagram 3.6 (cont.)

In order to have a more detailed picture on the existing pollution, an attempt was made to assess the full picture of possible changes in the quality of waters in Debed River, based on the data collected from the samples taken by EIMC from the gaging stations. Based on the data of 2005-2007, taken from each gaging station, the Canadian Index was calculated for 31 elements, based on a de fi ned methodology. The index values are within a range of 1-100, and the water quality is classi fi ed by fi ve categories. The index values and the water quality classi fi cation by the Canadian Index are shown below: Table 3.4. Water quality classi fi cation by Canadian Water Quality Index (CWQI) Category Quality Color CI value Water quality description I Excellent 95-100 The water quality is well maintained, there is no threat to water quality, the total condition is close to the original II Good 80-94 The water quality is well maintained, there

are only several slight deviations, the general condition is slightly different from the original.

III

Satisfactory

65-79 The water quality is maintained mainly, there are seldom threats to the quality of water, the general condition is sometimes below the preferrable 45-64 The water quality worsens regularly, the conditions have changed from the original 0-44 The water quality is permanently negative, the conditions usually differ from the original

IV

Poor

V

Very Poor

35

CHAPTER 3: STATE OF THE ENVIRONMENT

Environmental Knowledge for Change