 Treatment
of wastewater in the Caspian Sea region is inadequate. The likely future pollution loading
has been calculated from conservative estimates of the treatment potential in the region,
including conventional municipal wastewater systems, improved environmental performance of
industries by cleaner technology scenarios and pollution prevention measures and through
better river management.
Three scenarios for the upgrading of collection and
wastewater systems are presented:
All cities with municipal wastewater of <15,000 p.e.
[population equivalent] discharging direct into the Caspian Sea will be covered by
collection systems and mechanical treatment of the wastewater; Cities with loads
>15,000 p.e. will have additional biological treatment. This is to comply – more or
less – with national intentions of most riparian countries. Expected load reduction: BOD
83%, Total-N 25%, Total-P 29% and E.coli 85%.
All wastewater to be treated in accordance with EU
discharge standards for sensitive areas, thus all discharges >10,000 p.e. must be
covered by mechanical and biological treatment for N and P removal. Estimated load
reduction: BOD 83%, Total-N 70%, Total-P 79% and E.coli 99%.
As Scenario 1 but with nitrogen removal for all cities
with >100,000 p.e. plus phosphorus removal for those located on the northern coastline
of the Caspian Sea where the water is shallow and has low salinity. Expected load
reduction: BOD 83%, Total-N 62%, Total-P 36% and E.coli 96%.
In addition, sea out falls should be constructed at
existing treatment plants, suitable for upgrading, or at new localities where the
construction of new treatment plants are planned.
Reductions in % of total pollution loads to the
Caspian Sea with treatment scenarios
| |
BOD |
Nitrogen |
Phosph. |
E.Coli |
Oil |
Hg |
Cd |
| Sources |
|
|
|
|
|
|
|
| Rivers |
40 |
25 |
10 |
60 |
7 |
50 |
50 |
| Municipalities |
83 |
25 |
17 |
100 |
74 |
0 |
0 |
| Industries |
76 |
0 |
0 |
0 |
82 |
90 |
83 |
| Atmosphere |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
| Total |
46 |
24 |
10 |
61 |
34 |
52 |
50 |
Total pollution load to the Caspian Sea with treatment scenarios
| |
BOD |
Nitrogen |
Phosph. |
E.Coli |
Oil |
Hg |
Cd |
| Sources |
T/y |
T/y |
T/y |
10^15 C/y |
T/y |
T/y |
T/y |
| Rivers |
385 000 |
620 000 |
79 000 |
58 000 |
70 000 |
7,00 |
71,0 |
| Municipalities |
14 000 |
18 000 |
5 000 |
17,0 |
5 000 |
1,00 |
2,0 |
| Industries |
6 000 |
2 000 |
1 000 |
0 |
5 000 |
0,20 |
1,0 |
| Atmosphere |
0 |
39 000 |
800 |
0 |
350 |
0 |
0 |
| Total |
405 000 |
679 000 |
85 800 |
58 017 |
80 350 |
8,20 |
74,0 |
|
|
    
|
