SIRVAN DAM AND HEPP PROJECT

A) PROJECT DEFINITION

1. General

Sirvan Dam located in Turkey’s South-East Region, located on Kezer is a branch of Botan River. 15 km south-west of Siirt province Sirvan district and Finnik Village 2 km from Siirt-Sirvan highway.

Sirvan Dam and HEPP Project structures follows:

Clay core rock fill type dam
Gated discharge spillway in right bank
Derivation tunnel with circular section in right bank
Reinforced concrete water intake structure with sloped grid on right bank
Circular section energy tunnel and surge shaft on right bank
2 units plant on right bank
Access Roads and Site Buildings

These structures defined in details one by one chapter as follows.

2. Şirvan Dam

Dam body made of clay core and rock fill. Thalweg elevation 617 m and crest elevation is 690 m.

3. Spillway and Water Intake

Spillway, which located on the right bank and gated discharge, controlled by 4 times 6x8 m gates. For energy dissipater design ski-jump type is chosen. Water intake entrance elevation 651.44 m.

4. Power Tunnel

Power tunnel placed on the right bank. Power tunnel designed length of 4098.57 m, has a section circular diameter of 4 m, concrete lining.

5. Diversion Tunnel and Cofferdam

Derivation tunnel designed in left bank with diameter of 5 m. Derivation tunnel entrance base elevation 622 m, length 409.38 m, , exit base elevation 619 m. Crest elevation of upstream cofferdam 653 m and crest elevation of downstream cofferdam 622 m

6. Plant

Plant building and switchyard placed on right bank due to the topographic and geologic conditions. On ground plant contains two Francis turbines and two generators.

7. Transmission Line Connection

Transmission line 34, 5 kV, 477 MCM and 18 km length to the Siirt.

8. Access Roads and Site Buildings

İstanbul-Ankara-Kurtalan railway ends in Kurtalan. From Kurtalan there is a 30 km connection road to the Siirt. After 25 km from Siirt there is a branch to the Finnik Village. There has 2 km from there to the dam. There is a need of road for stripping, alluvial excavation, spillway excavation, rock pit, sand pit.

B) PROJECT DATAS

1. River Data

Mean Discharge =14.1 m³/s

Drainage Basin =824.00 km²

Q100 =584.3 m³/s

Suggested Energy Facility Project Flow (max.) =31.97 m³/s

2. Climatological Data

Maximum Mean Temperature =44.4°C

Minimum Mean Temperature =16°C

3. Dam Data

Dam’s general characteristics as follows

Dam Body

Location = 15 km S-W of Şirvan District, 2 km west of Finnik Village.

Type =Clay Core, Rock Fill

Crest Elevation =690 m

Thalweg Elevation =617 m

Height from the foundation =90.50 m

Height from Thalweg =73.00 m

Crest Length =215.09 m

Crest Width =10 m

Upstream Slope =1 vertical / 2 horizontal

Downstream Slope =1 vertical / 1.9 horizontal

Reservoir

Maximum water elevation =688 m

Normal water elevation =688 m

Operating elevation =688 m

Minimum operating elevation =667 m

Minimum water level =648 m

Dead storage level =648 m

Reservoir Volume in Max. Water Elevation =147 hm³

Reservoir Volume in Min. Operating Elevation =53 hm³

Useful storage =135 hm³

Reservoir Area in Max. Water Elevation =5.85 km2

Reservoir Area in Min. Water Elevation =3.18 km2

4. Tail Water Data

Tail Water Elevation =577.00 m

5. Power Tunnel Data

Location =Right Bank

Type =Circular Diameter 2.00 m

Length =4,098.57 m.

Flow =31.97m3/s

6. Spillway Data

Spillway Location =Right Bank

Spillway Type =Gated Discharge

Gate Count =4

Gate Dimensions =6 m x 8 m

Capacity: =1140 m³/s

Approach Channel Elevation =678 m

Threshold Elevation =680 m

Total Crest Length =30 m

Discharge Channel Length =84.35 m

Energy Dissipater Type =Ski-Jump Threshold

7. Derivation and Cofferdams

Derivation Location =Left Bank

Derivation Pattern =Circular Tunnel

Derivation Capacity =237.33 m³/s

Derivation Tunnel Diameter =5 m

Derivation Tunnel Length =409.38 m

Derivation Tunnel Entrance Base Elevation =622.00 m

Derivation Tunnel Exit Base Elevation =619.00 m

Penstock Diameter =0.80 m

Penstock Length =190.65 m

Upstream Cofferdam Crest Elevation =653.00 m

Upstream Cofferdam Crest Width =7.00 m

Upstream Cofferdam Slopes =Upstream 1.0 V / 2.5 H, downstream 1.0 V / 2.0 H

Upstream Cofferdam Crest Elevation =622,00 m

Downstream Cofferdam Crest Width =6.00 m

8. Plant Data

Maximum Facility Design Flow =30.60 m³/n

Maximum Head =101.50 m

Turbine Type and Count =Francis, 2