- Task: Feasibility study review,Detailed Design and Construction supervision
- Capacity: 14.9 MW
- Status: Completed
Salient features (as per Final Review of Feasibility Study Report, 2011):
| General | |
| Development region | Eastern |
| Zone | Mechi |
| District | Panchthar |
| District headquarter | Phidim |
| VDCs | Bharapa, Yangnam and Nangin |
| Project location | |
| Longitude | 87° 49′ 40″ E to 87° 47′ 21″ E |
| Latitude | 27° 11′ 8″ N to 27° 10′ 1″ N |
| Type of scheme | Run of river (RoR) |
| Source river | Hewa Khola |
| Access | Calcutta sea port (India) to Nepal-India border Jogbani
Jogbani-Biratnagar-Charali-Ilam-Phidim (about 300 km black topped double lane two way traffic plain and hill road) Phidim-Hewa Khola Bridge (about 15 km, black topped double lane two way traffic hill road) Hewa Khola Bridge-Powerhouse site (about 5 km, earthen fair weather single lane two way traffic access road) |
| Hydrology | |
| Catchment area | 208 km2 (at intake) |
| Mean annual precipitation | 2333.78 mm |
| Design discharge | 8.12 m3/s (Q40%) |
| 1 in 100 years return period design flood at intake | 989 m3/s |
| Power and energy | |
| Gross head | 221.52 m |
| Installed capacity | 14900 kW |
| Dry season energy | 13.449 GWh |
| Wet season energy | 71.311 GWh |
| Annual energy | 84.760 GWh |
| Project components | |
| Weir | |
| Type | Low height boulders lined with concrete cut-off walls |
| Crest level | 867.50 m amsl |
| Length of weir | 47.00 m |
| Spillway type | Free overflow |
| Sluice way | |
| Number | 1 |
| Invert level | 863.20 m amsl |
| Gate opening sizes | 3.00 m (w) X 2.50 m (h) |
| Intake | |
| Type | Gated side orifice intake with coarse trash rack |
| Nos. of opening | 2 nos. |
| Opening size (single orifice) | 5.00 m (w) X 1.00 m (h) |
| Sill level | 866.00 m amsl |
| Trash rack clear opening | 100 mm |
| Thickness of bar | 25 mm |
| Gravel trap | |
| Type | Continuous flushing hopper type |
| Overall length | 21.00 m |
| Width | Varying (11.00 m to 6.00 m) |
| Depth (below intake sill level) | 2.50 m (Maximum) |
| Particle size to be
trapped |
5.00 mm |
| Approach culvert | |
| Type | RCC box culvert |
| Length | 65.80 m |
| Width | 3.00 m |
| Height | 2.20 m |
| Design flow | 8.12 m3/s |
| Flow type | Non pressurised |
| Settling basin | |
| Type | Double chamber, gravity flushing type |
| Settling zone length | 60.00 m |
| Inlet transition length | 35.50 m |
| Single basin width | 8.50 m |
| Overall depth | 6.80 m (Maximum) |
| Particle size to be settled | 0.2 mm with 90% settling efficiency |
| Design flow | 8.12 m3/s |
| Headrace tunnel | |
| Type | Inverted D-shaped |
| Length | 3929.75 m |
| Width (excavation) | 3.20 m |
| Height (Excavation) | 3.20 m |
| Longitudinal slope | Varying form 1:60, 1:200, 1:500, 1:1000 and 1:2000 |
| Design flow | 8.12 m3/s |
| Khang Khola Crossing | |
| Type | Simply supported steel pipe |
| Span | 27.00 m |
| Diameter of steel pipe | 1750 mm (internal) |
Surge shaft |
|
| Type | Circular RCC lined |
| Effective diameter | 6.00 m |
| Height | 46.75 m |
| Free board | 2.95 m |
| Penstock | |
| Type | Mild steel circular shaped |
| Length | 375.30 m (exposed) |
| Internal diameter | 1750 mm |
| Thickness | 10 to 30 mm |
| Design flow | 8.12 m3/s |
| No. of anchor blocks | 12 |
| Branch pipe diameter | 1250 mm (internal) |
| Branch pipe thickness | 25 mm |
| Branch pipe length | 45.50 m |
| Closing & opening time | 15 sec |
| Powerhouse | |
| Type | Surface type, RCC framed structure |
| Length | 35.00 m |
| Width | 12.80 m |
| Height | 22.60 m |
| Tailrace | |
| Type | Box culvert |
| Length | 25.75 m |
| Width | 3.50 m |
| Height | 2.00 m |
| Minimum tailwater level | 645.41 m amsl |
| Turbine | |
| Type | Francis |
| No. of units | 2 |
| Rated capacity | 7500 kW one unit |
| Turbine axis level | 644.91 m amsl |
| Design flow | 4.06 m3/s for one unit |
| Generator | |
| Type | 3 Phase brushless synchronous |
| No. of units | 2 |
| Rated capacity | 7500 kW each |
| Governor | Servo motor actuated PID electronic flow governor |
| Overhead crane | Lifting capacity 32/5 Ton |
| Step up transformer | |
| Type | 3-Phase, two windings, oil immersed transformer, oil-nature-circulation cooling, with tap-changer and auxiliaries and spare equipments Outdoor type |
| No. of units | 2 |
| Rating | 10,000 kVA, 6.3/132 kV, 50 Hz |
| Transmission line | 132 kV single circuit, 3 phase, 50 Hz, 5 km long up to Soktim Danda |
| Grid connection point | Panchthar substation at Soktim Danda |
| Access road | Earthen road, 10 km long |
| Financial indicator | |
| B/C ratio | 1.18 |
| IRR | 16.44% |
| ROE | 23.57% |
| Total project cost | NPR 2,235,060,000.00 |
Construction Supervision and Design Support During Construction
HRE III
