Doodhpokhari Chepe Hydropower project (DPCHP) is a 8.836 MW Run of River (RoR) type of project located at Ajirkot Rural Municipality and Doodhpokhari Rural Municipality of Gorkha and Lamjung district, Gandaki province 4.
The project is about 182 km (aerial) north west of Kathmandu and is situated within Latitude 28°15’02” N to 28°16’52” N and Longitude 84°38’30” E to 84°40’25” E. The project utilizes a design discharge of 1.26m3/s from chepe khola and the elevation difference between the proposed intake at chepe khola and powerhouse for power generation.
The proposed headworks is located at Ajirkot Rural Municipality ,ward no 2, kalo patal phedi (about 3 hr of walk from olang village) and powerhouse area is also located at Ajirkot Rural Municipality, Taal bagar ( about 1.5 hr of walk from olang village). The distance from Taal bagar ( powerhouse ) to Kalo patal phedi( Intake) which is 5km.
The project consists Intake, Bed sluice chamber, Gravel trap, Approach conduit, Desander, Headrace Pipe, Surge tank, Penstock pipe, powerhouse and a tailrace canal.
| 1. Project Location | ||
| Province No. | : | 4 (Four) |
| Development Region | : | Western Development Region |
| Zone | : | Gandaki |
| District | : | Gorkha |
| Intake Site | : | Ajirkot Rural Municipality |
| Powerhouse Site | : | Ajirkot Rural Municipality |
| Geographical Co-ordinates | ||
| Latitude | : | 28°15’02” N – 28°16’52” N |
| Longitude | : | 84°38’30” E – 84°40’25” E |
| 2. General | ||
| Name of River | : | Chepe Khola |
| Nearest Town | : | Siraan Danda |
| Type of Scheme | : | Run-of- the-River |
| Gross Head | : | 882.30 m |
| Net rated Head | : | 846.08 m (minimum) |
| Installed Capacity | : | 8.836 MW |
| Average Annual Energy after Outage | : | 56.19 GWh |
| 3. Hydrology | ||
| Catchment Area | : | 27.64 km2 |
| Mean Annual Discharge | : | 2.67 m3/s |
| Design Discharge (at 45 % of Exceed.) | : | 1.26 m3/s |
| Riparian Release | : | 0.055 m3/s |
| Design Flood Discharge | : | 88.66 m3/s |
| Average Annual Precipitation | : | 2776 mm |
| 4. Diversion Weir | ||
| Type of Weir | : | Free Flow weir |
| Length of Weir | : | 11 m |
| Crest Elevation | : | 2762.30 m |
| 5. Intake Structure | ||
| Type of Intake | : | Orifice type side intake |
| No. of Openings | : | 2 |
| Size of Intake (W x H) | : | 1.5 m x 1.54 m (each) |
| Intake Sill Level (Invert Level) | : | 2761.3 m |
| 6. Bed Sluice Chamber | ||
| Length of Bed Sluice Chamber | : | 3.22 m |
| Width of Bed Sluice Chamber (Avg.) | : | 3.98 m |
| Overall depth | : | 3.74 m (with free board) |
| Particle size to be trapped | : | 300 mm or less |
| Flushing Channel | : | 0.6m x 0.6 m (B x H) |
| 7. Gravel Trap | ||
| Length of Gravel Trap | : | 8.0 m |
| Width of Gravel Trap (Avg.) | : | 2.6 m |
| Overall depth | : | 4.65 m (with free board) |
| Particle size to be trapped | : | > 5 mm |
| Flushing Channel | : | 0.5m x 0.5 m (B x H) |
| 8. Approach Conduit | ||
| Type | : | Circular |
| No. of Pipes | : | 1 |
| Length | : | 221 m |
| Pipe Diameter | : | 1.0 m |
| No. of Anchor Blocks | : | 6 |
| No. of Saddle Supports | : | 30 |
| 9. Desanding Basin | ||
| Type | : | Dufour Type |
| No. of Chambers | : | 2 (Two) |
| Dimension (L x B x H) | : | 36 m x 3 m x 5.5 m (each) |
| Inlet Transition Length | : | 9.5 m |
| Particle Size to be settled | : | 0.2 mm |
| Trapping Efficiency | : | 95 % |
| 10. Headrace Pipe | ||
| Type | : | Headrace pipe (Surface / Buried) |
| Internal Diameter | : | 1.0 m |
| Length | : | 1755 m |
| Steel Thickness/Type of Lining | : | 6 mm |
| No. of Anchor Blocks | : | 42 |
| No. of Saddle Supports | : | 220 |
| 11. Surge Pipe | ||
| Type | : | Surge Pipe |
| Effective Depth | : | 32 m |
| Diameter (Or size) | : | 1.5 m |
| Up Surge Level | : | 2777.05 m |
| Down Surge Level | : | 2747.05 m |
| Normal Operation Level | : | 2757.50 m |
| Steel Penstock Pipe | ||
| 12. Type | : | Penstock pipe (Buried) |
| Material (Steel) | : | IS 2062: E 300 (Fe 440) or Equivalent |
| Internal Diameter | : | 0.5 m to 1.0 m |
| Length | : | 3119 m (Actual Length) |
| Steel Thickness | : | 7 to 36 mm |
| No. of Anchor Blocks | : | 65 |
| No. of Saddle Supports | : | 390 |
| 13. Powerhouse | ||
| Type | : | Surface Powerhouse |
| Size (L x W) | : | 37 m x 17.22 m |
| Height | : | 16.5 m |
| Turbine Axis Level | : | 1880 m |
| 14. Tailrace | ||
| Type | : | Rectangular Canal |
| Tailrace Length | : | 47 m (approximate) |
| Size (W x D) | : | 1.5 m x 1.5 m |
| Tailrace Water Level | : | 1876.6 m |
| 15. Turbine | ||
| Type | : | Pelton, horizontal axis |
| Number | : | 2 |
| Rated Output Capacity per unit | : | 4.7 MW |
| Turbine Axis Level | : | 1880 m |
| Gross Head | ||
| Net Head | : | 846.08 m (minimum) |
| Discharge per Unit | : | 0.63 m3/s |
| Efficiency | : | 89 % |
| 16. Governor | ||
| Type | : | Solid state, PID control |
| Adjustment for Speed Drop | : | Between 0 to 10% |
| 17. Generator | ||
| Type | : | Salient pole, Synchronous |
| Rated Output Capacity per Unit | : | 5.3 MVA |
| Power Factor | : | 0.85 |
| Voltage | : | 11 kV |
| Frequency | : | 50 Hz |
| No of Units | : | 2 |
| Excitation System | : | Brushless Type |
| Efficiency | : | 96 % |
| 18. Transformer | ||
| Type | : | Outdoor, Oil immersed, Three phase |
| Rated Capacity | : | 11 MVA |
| Voltage Ratio | : | 11/33 kV |
| No of Units | : | 1 |
| Vector Group | : | YNd11 |
| Efficiency | : | 99% |
| 19. Transmission Line | ||
| Voltage Level | : | 33 kV, Double circuit |
| Length | : | 28 km (approximate) |
| Conductor Type | : | Dog |
| From | : | Powerhouse |
| To | : | 33 kV Hub Kirtipur Sub-station, Lamjung |
| 20. Construction Period | : | 2.5 years |
| 21. Power and Energy | ||
| Installed Capacity | : | 8.8 MW |
| Estimated Annual Sellable Energy | : | 56.19 GWh |
| Dry | : | 19.28 GWh |
| Wet | : | 36.91 GWh |
Developed By: Bipin Bhandari
