1. Assessment of ecological status according to the Water Framework Directive - intercalibration among Western-Balkan countries -
Preparing by Pavle Đurašković
Institute of Hydrometeorology and Seismology Podgorica
Kick off Meeting, Ohrid July 2015

2. Objects: Black and Biogradsko Lakes
Kick of Meeting, Ohrid 2015
Objects: Black and Biogradsko Lakes
Glacier lakes / without direct (bigger) anthropogenic pollution sources
Regular monitoring (Black Lake):
IHMS is responsible institution (quality and quantity parameters)
Physical-Chemical and microbiological parameters
June-October / monthly
Surface water / one measuring point

3. The biggest lake at Bjelasica mount.
Kick of Meeting, Ohrid 2015
Biogradsko Lake (I)
The biggest lake at Bjelasica mount.
Lake is situated at its South-Western side.
Lake is a part of national park, named Biogradska gora.
NP ``Biogradska gora`` includes Biogradska jungle one of two remained at Balkan peninsula.
Lake is linked with main road Kolašin-Mojkovac by asphalt road.
The distance of lake from Mojkovac is 12km, but from Kolašin -16km.
Altitude of Lake is 1094m;
Long: 42°53'58.96“N
Lat: 19°35'52.59“E

4. Lake belongs to accumulation type.
Kick of Meeting, Ohrid 2015
Biogradsko Lake (II)
Lake belongs to accumulation type.
Length is 875m (at water level of 6,50m) Max depth 12,1m (average 4,5m)
Max extent 410m
Water level is very variable: Maximal is in April and December; Minimal is in September and October.
During a ``small waters`` -in summer, water level decreases to 4-6m, depth to 5-6m, length to 400m, and extent to 200m.
Than, the Lake`s surface is m2,
and water volume m3.
Long: 43° 8'46.14“N
Lat: 19° 5'32.70“E

5. Tributaries: Biogradska river and stream Bendovac,
Kick of Meeting, Ohrid 2015
Biogradsko Lake (III)
Water balance:
Tributaries: Biogradska river and stream Bendovac,
Outflow: Jezerštica, tributary of Tara river.
Lake`s water outflow by sinks, cavern trias limestone at NW littoral of lake and at bottom.
Rain deposition directly at lake surface is a main contribution in water balance (annual average of deposition is >2000mm).
Coastline is jagged and 3300m long.
Biogradska river has a delta at Eastern side of Lake, but Nordern coast of lake is characteristic with lush forests, mainly beech.
The main part of 31,3km2 watershed area is under forest cover, than under meadow and small part is barren land.

6. Lake bottom covered by hydrophilic vegetation.
Kick of Meeting, Ohrid 2015
Biogradsko Lake (IV)
Lake bottom covered by hydrophilic vegetation.
During winter the water is frozen.
Than there is an inverse temperature stratification.
Izotermal conditions have established in spring which fast transformed in normal temperature stratification.
Insufficient measuring data show that the water is generally a little alkaline, without nitrite and ammonia.
The presence of Zn and Cd (water, sediment and snow) can be of anthropogenic origin (TP Pljevlja, landfill Mojkovac…)
Biogradsko lake is threatened by increased outflow over Jezerštica and primarily through the bottom sinks.

7. Lake is linked with Žabljak by asphalt road.
Kick of Meeting, Ohrid 2015
Black Lake (I)
Lake is situated into coniferous forests, within national park ``Durmitor``
Lake is linked with Žabljak by asphalt road.
There is not any main pollution sources in surrounding of the Lake.
Lake consists of hydrological complex of two linked water basins: The Big and the Small Lakes.
Black Lake is of poligenetic type. Its parts formed at contact of limestone and verfen sandstone.

8. Length is 1115m, and extent 810m, at water level of 1422mnm.
Kick of Meeting, Ohrid 2015
Black Lake (II)
Length is 1115m, and extent 810m, at water level of 1422mnm.
Separatelly, The Big lake is long 855m, and wide 615m, but The Small is long 605m, and wide 400m.
Midriff between them is long 60m. At summer water level these numbers go down.
Coast line is poorly jagged: in spring it is long 4 395m (The Big m, The Small m). Lake`s coast is mainly steep and rocky, specially at The Small Lake. Maximal depth of The Small lake is 49,1m (average – 25,5m), and the Big Lake - 24,5m (average- 12,2m).
The surface of Black Lake is m2, at maximal water level.

9. Black Lake (III) Water balance:
Kick of Meeting, Ohrid 2015
Black Lake (III)
Water balance:
The outflow is Žabljačka river which is now underground, near Žabljak, and bottom caves.
The tributaries are Mlinski stream, periodical streams, surface and sub-lacustric springs, also atmospheric deposition (average deposition is 1422mm).
The variation of water level of The Big Lake is about 5m, at small water level, the level of the Small Lake is 4-6m, lower than The Big Lake, so the total variation of water level of the Black Lake 8-10m.

10. System of Black Lake shows a bifurcation.
Kick of Meeting, Ohrid 2015
Black Lake (IV)
System of Black Lake shows a bifurcation.
The vacancy functions as sub-lacustric spring during the spring, but during the summer as abyss.
In the first case, water of The Small lake goes to The Big Lake, and than toward to Tara river.
In second case, water of The Big Lake goes to The Small Lake and, by abysses toward to Piva river.
In shallow parts of The Big Lake has developed a hydrophilic vegetation at the bottom.

11. Thank you for attention …………. questions ?