solu khola (dudh koshi) hydroelectric project...

SOLU KHOLA (DUDH KOSHI) HYDROELECTRIC PROJECT (86MW)

Progress Report # W07

(March 2018 - May 2018)

Submitted by:

Sahas Urja Ltd. (SUL)

Hattisar, Kathmandu, Nepal

June 2018

Sahas Urja Ltd. Progress report of SKDKHEP # W07

June 2018 i

Table of contents

Chapter 1 About the Company .................................................................................................. 1

Description of the Company ........................................................................................... 1

Board of Directors........................................................................................................... 1

Organization Structure .................................................................................................... 2

Chapter 2 Project Description .................................................................................................... 3

Project Background ......................................................................................................... 3

Project Location and Accessibility ................................................................................. 3

Salient Features ............................................................................................................... 5

Project Layout ................................................................................................................. 8

Summary of activities performed .................................................................................... 9

Chapter 3 Pre-construction and Infrastructure Works ............................................................. 12

Land Acquisition ........................................................................................................... 12

Access Road and Bridge ............................................................................................... 12

Camp and Other Facilities ............................................................................................ 15

Transmission Line ......................................................................................................... 15

Physical Modelling ....................................................................................................... 16

Chapter 4 Employer’s Representative Mobilization ................................................................ 17

Chapter 5 Civil Construction Works ........................................................................................ 18

Contractor’s Mobilization ............................................................................................. 18

Explosive....................................................................................................................... 20

Civil Works ................................................................................................................... 20

5.3.1 General ............................................................................................................... 20

5.3.2 Surface Structures .............................................................................................. 21

5.3.3 Powerhouse ........................................................................................................ 21

5.3.4 Underground Structures ..................................................................................... 22


June 2018 ii

5.3.5 Headrace Tunnel ................................................................................................ 22

5.3.6 Adit Tunnels....................................................................................................... 22

i) Adit 2, 2.1 and 2.2 ..................................................................................................... 22

ii) Adit 4 ..................................................................................................................... 23

Chapter 6 Mechanical and Electrical Works ........................................................................... 24

Hydro-Mechanical Works ............................................................................................. 25

Electro-Mechanical Works ........................................................................................... 25

Transmission Facilities ................................................................................................. 25

Chapter 7 Social Works ........................................................................................................... 26

Annex:1 Some Additional Photos ............................................................................................ 28


June 2018 iii

List of Figures

Figure 1 Organizational structure .............................................................................................. 2

Figure 2. Project Location on District Map ............................................................................... 4

Figure 3. Project Layout ............................................................................................................ 8

Figure 4.Revised Headworks - General Layout based on finalized Physical Modelling .......... 8

Figure 5. Powerhouse and Switch Yard ..................................................................................... 8

Figure 6 EPC Engineer’s proposed penstock profile ................................................................. 9

Figure 7. Project Access Road network ................................................................................... 12

Figure 8. Road A section ......................................................................................................... 13

Figure 9. Road B upgradation work ......................................................................................... 13

Figure 10. Soling work at Road C section ............................................................................... 14

Figure 11. Road D upgradation work at Panchan Bhanjyang .................................................. 14

Figure 12. Road E section ........................................................................................................ 14

Figure 13. Road F view ............................................................................................................ 14

Figure 14. Bailey Bridge 1. ...................................................................................................... 14

Figure 15. Bailey Bridge 2. ...................................................................................................... 14

Figure 16. Headworks Camp Area........................................................................................... 15

Figure 17. Powerhouse camp area. .......................................................................................... 15

Figure 18: Transmission line route in Google Image .............................................................. 16

Figure 19. Visit of Design team at Hydro Lab......................................................................... 16

Figure 20. Representatives of Financing Institutions at Hydro Lab. ....................................... 16

Figure 21. Organization chart of Employer’s Representative at site ....................................... 17

Figure 22. Contractor's organization chart ............................................................................... 18

Figure 23. Contractors Camp at Headworks area. ................................................................... 19

Figure 24. Contractor's camp at Powerhouse area. .................................................................. 20

Figure 25. Bunker near Surge Tunnel Area ............................................................................. 20


June 2018 iv

Figure 26. Army Camp near Surge Tunnel area. ..................................................................... 20

Figure 27. Shotcrete work at Inlet Portal. ................................................................................ 22

Figure 28. Drilling at headrace tunnel using Boomer. ............................................................. 22

Figure 29. Revised Adit 2 map ................................................................................................ 23

Figure 30. Shotcreting work at Adit 2.1. ................................................................................. 23

Figure 31. Adit tunnel Progress ............................................................................................... 23

Figure 32. Geological investigation at Adit 4. ......................................................................... 24

Figure 33. Adit 4 Progress. ...................................................................................................... 24

Figure 34. Road extension work at Ramite .............................................................................. 26

Figure 35. Social Road upgradation work ............................................................................... 26

Figure 36. Inauguration of Training Program .......................................................................... 27

Figure 37. Program coordinator with Trainers ........................................................................ 27

Figure 38. Participants of off-season farming .......................................................................... 27

Figure 39. Participants working in the field ............................................................................. 27

Figure 40. Participants receiving certificate ............................................................................ 27

Figure 41. Group picture after certificate distribution ............................................................. 27

Figure 42. New headworks design after modification ............................................................. 28

Figure 43. Modified headworks design with three settling basin ............................................ 28

Figure 44. Meeting with CMC and FIH at site office. ............................................................ 28

Figure 45. Site Visit of technical team. .................................................................................... 28

Figure 46. Container being transported at powerhouse. .......................................................... 28

Figure 47. Fencing work at army camp area. ........................................................................... 28

Figure 48. Site preparation for labour camp and batching plant. ............................................. 29

Figure 49. Camp at Headworks area. ....................................................................................... 29

Figure 50. Bridge 2 installation progress. ................................................................................ 29

Figure 51. Bailey Bridge 2 ....................................................................................................... 29


June 2018 v

Figure 52. Contractor's equipment at site. ............................................................................... 29

Figure 53. Expatriate camp at Headworks ............................................................................... 29

Figure 54. Adit 2.1 Portal preparation. .................................................................................... 30

Figure 55. Adit 2.1 tunnel progress ......................................................................................... 30

Figure 56. Metal works at site. ................................................................................................. 30

Figure 57. View of Adit Tunnel. .............................................................................................. 30

Figure 58. Geological investigation at Adit 3 area. ................................................................. 30

Figure 59. Sample of rock during Geological investigation at Adit 3 ..................................... 30

Figure 60. Safety signals at site. .............................................................................................. 31

Figure 61. Adit 2.1. .................................................................................................................. 31

Figure 62. Access Road ........................................................................................................... 31

Figure 63. Boulder Riprap at Maikhu Kholsi. ......................................................................... 31

Figure 64. Retaining wall at Ramite road. ............................................................................... 31

Figure 65. Social Road upgraded by Sahas Urja Ltd. .............................................................. 31


June 2018 vi

List of tables

Table 1. Company details .......................................................................................................... 1

Table 2. Board of Directors ....................................................................................................... 1

Table 3. Project Salient Features .............................................................................................. 5

Table 4. Summary of activities completed till February, 2018 .................................................. 9

Table 5. Summary of recent activities completed from March 2018 to the end of May 2018 11

Table 6. List of Access Roads of Project. ................................................................................ 13

Table 7. Personnel of Employers Representative at Site ......................................................... 17

Table 8. Manpower of EPC contractor at site. ......................................................................... 18

Table 9. Major Plant and equipment of EPC contractor at site. .............................................. 19

Table 10. List of Road constructed for society ........................................................................ 26


June 2018 1

Chapter 1 About the Company

Description of the Company

Sahas Urja Limited established on 2071 B.S comprises of a group of veterans in the field of entrepreneurship having innovative ideas of modern enterprises with advanced development strategies and management concepts. Sahas Urja Ltd. commits to create superior value for all its shareholders and stakeholders and aimed to be among most admired and trusted company in the country. It has planned to contribute to the national economy through accelerated hydropower development.

Table 1. Company details

Company Sahas Urja. Ltd. Type Public Limited Company Address Hattisar, Kathmandu Establishment 2071/05/29 B.S. PAN no 601799749 Kathmandu Registration no. at Office of Company Registrar

126624/071/072

Department of Industry Registration No

2117/77/070/071 (2070-06-10)

Project under development Solu Khola (Dudh Koshi) Hydroelectric Project (SKDKHEP) -86 MW

Survey license no. of SKDKHEP BBB 065/066 B U S-435 Generation license no. of SKDKHEP BBB 71/72-B U. 126 Generation License date of SKDKHEP

September 18th 2014, 2071/6/2

Board of Directors

Table 2. Board of Directors

Name of Director Position Mr. Him Prasad Pathak Chairman Mr. Sushil Thapa Managing Director Mr. Min Raj Kandel Director Mr. Paritosh Paudyal Director Mr. Mahendra Kumar Giri Director Mr. Bhoj Bahadur Shah Director Mr. Mukti Ram Pandey Director


June 2018 2

Organization Structure

In any organization, the organizational structure plays a vital role in achieving the success. This

structure defines the role of each persons involved in the company. Following chart elaborates the organization structure of this company:

Figure 1 Organizational structure

Both site team and head office team will have a technical division and support division. Whereas the head office team comprise of finance division and site team has public relation division.

Board

Managing Director

Project Manager

Site Team

Technical Division

Support Division

Public Relation & Environment

Head Office Team

Technical Division

Finance Division

Support Division

Advisor

Chairman


June 2018 3

Chapter 2 Project Description

Project Background

Solu Khola (Dudh Koshi) Hydroelectric Project (SKDKHEP) is a Run of River (RoR) type

project with installed capacity of 86 MW that lies in Solukhumbu District of Sagarmatha Zone in the Eastern Development Region of Nepal. The Project was identified by Hydro Venture Pvt. Ltd (HVPL) in 2008. The proposed headworks site is located near Bhadaure Village in Dudhkunda Municipality. The tunnel passes underneath of Kattike, Gairi, Pokhari Bhanjyang, Phalate and Pairatham of Thulung Dudh Koshi Gaupalika. The proposed powerhouse site is located at Maikubesi of Thulung Dudh Koshi Gaupalika at about 1km upstream from the suspension bridge over Dudh Koshi River at Jaleshwor Mahadev. The major structures of the project are diversion weir, undersluice, intake, approach canal, surface settling basin, headrace tunnel, surge tunnel, underground penstock, surface powerhouse and tailrace box culvert. The energy generated from the project will be evacuated to the Integrated Nepal Power System (INPS) at the proposed sub-station at Lamane in Dudhkunda Municipality of Solukhumbu

District. Geographically, the physical area of the project lies within longitudes of 863735E

to 864115E and latitude of 272153N to 272515N.

DoED had awarded the survey license to the company on 2065-07-25 to conduct the necessary investigations, feasibility study and environmental impact assessment (EIA) of the project. Upon completion of feasibility study and EIA of the project in October 2013, Hydro Venture applied for the generation license with the DoED and presented among the concerned officials. DoED accordingly awarded the Generation License to HVPL on 2071-06-02 (18 September 2014).

The application for PPA was filed in February 2012 and regular follow ups were made with the Power Trade department of NEA. After the introduction of new tariff structure for projects up to 100 MW, PPA between HVPL and NEA was concluded on 25 February 2015.

The Financial Closure has been concluded with 11 Banks and Financial Institution with the lead by Nepal Investment Bank Limited (NIBL) on 2073/4/20. HVPL was involved in acquisition of private land and development of infrastructures like access road and camp facilities of the Project till 23rd Chaitra 2073. After acquiring Hydro Venture Private Limited by Sahas Urja Limited (SUL), Sahas Urja Ltd is carrying out the infrastructure development works.

Project Location and Accessibility

The proposed headworks site lies at an elevation of 1264.0 m near Gairi Gaun of Tingla of Dudhkunda Municipality and the powerhouse is located at an elevation of 643 m at Maiku Besi of Thulung Dudh Koshi Gaupalika.


June 2018 4

The nearest motorable road head from the headworks site is at Ramite on Sagarmatha highway from where an agricultural road branches towards SKDKHEP headworks site. The Headworks site is about 257 km from Kathmandu including 250 km black topped road up to Ramite and 9 km earthen road from Ramite to headworks site. Similarly, there is accessibility from Mirchiya, East-West highway to Ramite through Katari-Ghurmi-Okhaldhunga which is 149 km in length.

Similarly, the nearest road head from the powerhouse site is Panchan which is 19 km from Jor-Buddha, Okhaldhunga- Salleri highway.

Figure 2. Project Location on District Map


June 2018 5

Salient Features

The salient features of the Solu Khola (Dudh Koshi) Hydroelectric Project 86MW, are

presented on Table 3

Table 3. Project Salient Features

a. Project Information

Development Region Eastern

Zone Sagarmatha

District Solukhumbu

Location

Latitude 27°21’53”N to 27°25’15”N

Longitude 86°37’35”E to 86°41’15”E

Intake Site Dudhkunda Municipality

Powerhouse Site Thulung Dudh Koshi Gaunpalika

b. General Data

Name of River Solu Khola

Type of Scheme Run-of-river

Head Gross 613.20 m

Net 598.09 m

Design Discharge 17.05 m3/sec

Installed Capacity 86,000 kW

Energy Dry Season 101.27 GWh

Wet Season 419.94 GWh

Total Annual 520.20 GWh

c. Hydrology Catchment Area 454 km2

40% Percentile Discharge 17.05 m3/sec

Design Flood (1 in 100 yr. return) 475 m3/s

d. Diversion Weir

Type of Weir Gravity

Length 31.8 m

Weir Crest Level El. 1,262.00masl

Foundation Level El. 1,248.50masl

e. Sluiceways

1. Bed Load Sluice

Openings 1 No. 3.0 m wide × 3.0 m high

Invert Level El. 1,253.50 masl

Length 15.85 m

2. Undersluice Openings 3 No. 1.5m wide × 1.0 m high

Invert Level El. 1256.00 masl

Length 30.85 m


June 2018 6

3. Sluiceway Canal Openings 1 No. 4.0 m wide × varies high

Length 86.36 m

g. Trash passage Opening 1 No. 3.10 m wide × 4.65 m high

Length 13.30 m

h. Fish Ladder

Opening Size 1 No. 2.00 m wide × 1.52 m high

Length 50.65 m

h. Intake Structure

Type Side intake

Openings 3 No. 4.0 m wide × 2.3 m high

Invert Level El. 1,258.00 masl

i. Gravel Trap

Size 3 No. 5m × 5m (LxB)

Bed load size to trap 5 mm

Flushing Pipe 3.0 Nos, 26.55m in total 0.5m dia

j. Approach Culvert

No. 3

Size 2.6 m wide × 2.6 m high

k. Settling Basin

No of Bays 3

Inlet Transition 22 m

Dimensions 85.0 m long × 9.0 m wide × 5 m high

Headpond Size 15.20 m

Nominal Size of Trapped Particle 0.15 mm

Trap Efficiency 90%

Power Conduit

l. Headrace Box Culvert

Length 34.50 m

Dimensions 1 No. 4.5 m wide × 4.5 m high

m. Tunnels – ‘Inverted D Shaped’

With Finished Inverted D Dimensions 4.0 m wide × 4.25 m high

Headrace Tunnel Length 4,503.0 m

Adit 1 96 m

Adit 2 30 m

Adit 2.1 30 m

Adit 2.2 250 m


Adit 3 170m

Adit 4 300 m


June 2018 7


Surge Tunnel 375.00 m

n. Penstock pipes

Horizontal section 1 240 m ( Upper )

Drop Shaft 1 185 m deep

Horizontal section 2 485 m long

Drop Shaft 2 255 m deep

Horizontal section 3 685 m long

Total length to trifurcation 1850.0 m

Pipe

Steel Grade 460 MPa

Internal Diameter and Length Diameter varies from 2.50 m Dia. 2.10 m Dia.

Thickness varies from 9 mm to 34 mm

o. Powerhouse

Type Surface

Dimensions 60 m Long × 16.2 m Wide × 18 m High

Turbine setting level El 647.30 masl

No. and Type of turbines 3 No. Vertical axis Pelton

Speed of Turbine 750 RPM

Total Installed capacity 86.0 MW

Generators Three phase, Synchronous, 34.6 MVA

p. Tailrace Canal- Length and Type 70 m long Reinforced Concrete Conduit

q. Transmission Line – Project to Proposed Tingla Substation

12 km long 132 kV

r. Switchyard 60 m long × 50 m wide


June 2018 8

Project Layout

General Project layout with the major projects components is shown in Figure 3.

Figure 3. Project Layout

The physical model conducted at Hydro Lab suggested new arrangement of headworks. The revised intake and waterway are shown on Figure 4, while the powerhouse is shown on Figure 5

Figure 4.Revised Headworks - General Layout based on finalized Physical Modelling

Figure 5. Powerhouse and Switch Yard

The EPC Engineer Lombardi Engineering Limited, after the field visit proposed an alternative for the penstock alignment. The proposed new penstock alignment (black line) is show on the figure below.


June 2018 9

Figure 6 EPC Engineer’s proposed penstock profile

Summary of activities performed

Following tables presents the key activities and progress of the project from the date of survey license to May, 2018.

Table 4. Summary of activities completed till February, 2018

SN Activities Dates

1. Award of Survey License by DoED. Nov-2008

2. Application for Power Purchase Agreement to NEA. Feb-2012

3. License Capacity Upgrade to 86 MW by DoED. Aug-2012

4. Connection Agreement with NEA. Jan-2013

5. EIA Study. Jan to Oct 2013

6. Registration at Department of Industry as Hydro Venture Ltd. 26 Sept 2013

7. Application for Generation License to DoED. Oct-2013

8. Award of Generation License by DoED. Sept. 2014


June 2018 10

SN Activities Dates

9. Conclusion of PPA with Nepal Electricity Authority. 25 Feb 2015

10. Application of survey license for transmission line to DoED. June 2015

11. Contract agreement for Detail Design & Tender Document preparation with Hydro Consult Engineering Limited.

Nov 2015

12. Extension of time for Financial Closure by DoED. Dec 2015

13. Application for debt financing to the Nepal Investment Bank Limited to lead the consortium of the financing institution.

Feb 2016

14. Start of Construction of Access road by Radha Krishna and Brother Construction Pvt. Ltd.

Mar 2016

15. Agreement with Geophysical Research and Consultancy Service Pvt. Ltd for geophysical investigation works.

April 2016

16. Agreement with ICGS Pvt. Ltd for core drilling works. April 2016

17. Report submission of Geophysical Investigation. May 2016

18. Award of Survey license for Transmission Line by DoED. May 2016

19. Agreement for river and hydraulic modelling with Hydro Lab Pvt. Ltd.

May 2016

20. Agreement with Integrated Engineering and Management Group for the supply of Explosive.

July 2016

21. Agreement with Nepal Environment and Development Consultant Pvt. Ltd. (NEDC) for IEE study of transmission line works.

July 2016

22. Financial Closure Concluded between HVPL and Consortium of 11 Banks and Financial Institution with the lead by Nepal Investment Bank Limited.

Aug 2016

23. Amendment of PPA for revised RCOD (Sept 26, 2020). Dec 2016

24. Final ToR for IEE of Transmission line submitted after incorporation of comment.

Feb 2017

25. Registration in Department of Industry as Sahas Urja Limited. April 2017

26. Generation License transferred by DoED to Sahas Urja Limited. May 2017

27. EPC Contract agreement signed with Cooperativa Muratori & Cementisti – C.M.C di Ravenna (Italy).

June 2017

28. Installation of Bailey Bridge 1 is complete. June 2017

29. NEA PPA transfer. July 2017

30. Survey License of Transmission line transferred in the name of Sahas Urja Ltd.

August 2017

31. Detail Design Report submitted by Consultant. September 2017

32. Land purchase limit approval obtained. September 2017

33. TOR for IEE for transmission line Approved. September 2017


June 2018 11

SN Activities Dates

34. Contract agreement with the Department of Forest regarding tree cutting and land use.

November 2017

35. Operation of Powerhouse camp started. December 2017

36. Track opening of access road completed. December 2017

37. Contract with the Consortium of Hydro-Consult Engineering Limited and Fichtner GmbH & Co.KG as Employer’s Representative/ Consultant.

December 2017

38. Ground breaking program of tunnel works. January 2018

39. Final approval for the use of explosive. February 2018

40. Mobilization of Employer’s Representative at site. February 2018

Table 5. Summary of recent activities completed from March 2018 to the end of May 2018

SN Activities Dates

1. Survey License for transmission line renewed. March 2018

2. Transmission Line IEE report Draft submitted to DOED. March 2018

3. Physical modeling and Headworks modification March 2018

4. Construction of bunker for Army camp and explosive storage. April 2018

5. Bailey Bridge 2 installation complete. April 2018

6. Vocational Training to the local People. April 2018

7. Inlet Portal Preparation work. May 2018

8. Adit 2.1 Portal Preparation. May 2018

9. Investigation work at Adit 3 area. Ongoing

10. Upgradation of Access road. Ongoing

11. Headrace tunnel work from inlet. Ongoing

12. Adit 2.1 tunnel work. Ongoing

13. Adit 4 tunnel work. Ongoing

14. Excavation of Powerhouse area Ongoing

15. EPC Contractors camp construction work. Ongoing


June 2018 12

Chapter 3 Pre-construction and Infrastructure Works

This topic covers the works required to be completed before the major construction work starts.

Following topics are covered by this topic and described in detail.

Land Acquisition

Based on different types of ownership, there are two types of lands required by the project i.e. governmental and private. Within this frame these lands are either leased till the project period or purchased. Most of the Private land required for the project component has already been purchased and taken in lease and few are in the process.

From the Ministry of Land Reform and Management approval for acquisition of 239 Ropani of land was obtained in the month of September 2017.

Contract agreement with the Department of Forest regarding tree cutting and land use has been done in the month of November 2017.

Access Road and Bridge

The access road from headworks to powerhouse is about 21.71 km. and crosses the Solu River two times. The road length from Ramite (nearest road head in Okhaldhunga - Salleri highway) to headworks is 9 km. Opening of track connecting headworks to Powerhouse is complete. Details of access road track constructed is listed in Table 6. At the same time, upgradation of access road is completed at most of the section.

Figure 7. Project Access Road network


June 2018 13

Table 6. List of Access Roads of Project.

S. N. Name of the

Road From-To Total Length

(km) 1 Road A Zero (Bhadaure)- Bridge 1 at Headworks 2.5002 Road B Junction of Road A and B- Bridge 2 1.5403 Road C Bridge 2- Thulodhunga 1.9464 Road D Thulodhunga – Panchan Bhanjyang 6.5025 Road E Panchan Bhanjyang – Bhorleni Site camp 2.1206 Road F Bhorleni site camp- Powerhouse 6.8037 Road G Bridge 1- Headworks 0.300

Total 21.711

The powerhouse is also accessible via Salleri-Tumse-Panchan Road or Jor-Buddha- Tumse -Panchan. Road from Tumse to Panchan was upgraded by Sahas Urja Ltd and also maintaining as and when required. From Panchan onwards Road E will be used to access Maikhubesi i.e. Powerhouse location.

At most of the locations road upgradation activities are completed. Till the end of May, approximately 11,552 m3 of gabion works, 1342 m3 of dry wall and 820 m3 of stone masonry works has been executed at site. Figure 8 and Figure 9 shows the access Road A and Road B sections.

Figure 9. Road B upgradation work

Figure 10 and Figure 11 shows the upgrade work on Road C and Road D. Similarly, Figure 12,

Figure 13 shows the sections of Road E and Road F.

Figure 8. Road A section


June 2018 14

Figure 10. Soling work at Road C section

Figure 11. Road D upgradation work at Panchan Bhanjyang

Figure 12. Road E section Figure 13. Road F view

Bailey Bridge

Construction of two bridges, Bridge-1 to access the headworks and Bridge-2 to connect

headworks and powerhouse in Solu Khola are already completed and in operation. Bridge -1 and Bridge-2 are of 30 R and 70 R according to Road Standards. The span of these bridge is 120 feet. The Figure 14 and Figure 15 shows the two Bailey bridge installed at site.

Figure 14. Bailey Bridge 1.

Figure 15. Bailey Bridge 2.


June 2018 15

Camp and Other Facilities

Camp establishment at Bhadaure near Headworks, Bhorleni, near Adit-2 and Surge tunnel area

and Maikhubesi near powerhouse has been completed.

There are five building blocks at headworks. Two for residential quarters for senior officers, one for driver and guard room, one kitchen and one office building. All the buildings are in use.

Similarly, there are five blocks at powerhouse with three senior residential quarters, one office block and one kitchen block. The camp is being used for accommodation since December 2017. Figure 16, Figure 17 shows the camp facilities at headworks and powerhouse area.

Figure 16. Headworks Camp Area.

Figure 17. Powerhouse camp area.

The camp facilities include furniture, mesh utensils, office equipment’s, TV, internet, recreational items etc.

Transmission Line

A transmission line walkover survey report has been submitted by the consultant. Along with this, a detail topographical survey has been completed by the consultant. DPR report consists of detail design of transmission line components. TOR of IEE for transmission line has been approved and IEE report Draft has been submitted to DOED. Figure 18 shows the transmission line route with the position of tower in google map.


June 2018 16

Figure 18: Transmission line route in Google Image

Physical Modelling

Physical hydraulic modelling of headworks was conducted in Hydro Lab Pvt. Ltd from May 2016 to March 2018. Based on the results of this model, revision of headworks arrangement was deemed necessary. After reviewing the physical model Professor Dr. Haakon Stole suggested some major changes in the arrangements. These were further tested in the laboratory for model study and was found satisfactory.

The EPC Engineer (Lombardi) visited Hydro Lab to observe the hydraulic performance of the headworks and also to observe the changes made from the tender drawings. They accepted the modified design for construction.

Figure 19. Visit of Design team at Hydro Lab

Figure 20. Representatives of Financing Institutions at Hydro Lab.

Figure 19 and Figure 20 shows the visit of EPC Engineer’s Team and representatives of financial institutions visiting the Hydro Lab respectively.


June 2018 17

Chapter 4 Employer’s Representative Mobilization

Contract has been awarded to Consortium of Hydro-Consult Engineering Limited and

FICHTNER GmbH & Co.KG on 18th December 2017 as an Employer’s Representative. A team of Consortium has already been mobilized at site.

Figure 21. Organization chart of Employer’s Representative at site

Currently there are 22 personnel at site. Table 7 shows the list of site personnel of Employers Representative.

Table 7. Personnel of Employers Representative at Site

S. No. Job Classification Number of personnel

1. Technical 13

2. Administrative / Account 2

3. Support Staff 7

Total 22


June 2018 18

Chapter 5 Civil Construction Works

Contractor’s Mobilization

Contractor’s team is at site since August 2017 building their camps at headworks and

powerhouse area which is now almost completed. Technical Consultant of the EPC contractor, Lombardi Engineering Limited from Switzerland has been designing the various components of work. Figure 22 shows the organization chart of EPC contractor.

Figure 22. Contractor's organization chart

Table 8 and Table 9 below shows the manpower, plant and equipment of the contractor at site.

Table 8. Manpower of EPC contractor at site.

S.N. Position Expatriate Nepalese1. Project Manager 1 2. Deputy Project Manager 1 3. Senior Geologist 1 4. Site Manager 5 5. Site Tunnel in-charge 2 6. Road Supervisor 1 7. Civil Engineer 18. Geologist 29. Surveyor 410. Lab Technician 211. Accountant 1


June 2018 19

S.N. Position Expatriate Nepalese12. Public Relation Officer 213. Supervisor 914. Technicians (Welder, Electrician, Mechanic, Blaster) 2815. IT technician 116. Safety officer 117. Operator for equipment 1118. Medical Staff 119. Helping staff 36

Sub-Total 11 100

Table 9. Major Plant and equipment of EPC contractor at site.

S. No. Particulars Number

1. Boomer 22. Excavator 11 3. Robodrill 1 4. Dump Truck 7 5. Generator 6 6. Forklift machine 1 7. Loader 2 8. Compressor 3 9. Concrete Mixer 5 10. Shotcrete machine 3 11. Grouting machine 1 12. Cutter Machine Electric 2 13. Welding Machine 3 14. Jack hammer Pneumatic 7 15. Drill Gun Machine Pneumatic 1

Figure 23 shows the temporary camp construction progress of EPC contractor at Headworks area, and Figure 24 shows the progress of camp construction work of EPC contractor near powerhouse

Figure 23. Contractors Camp at Headworks area.


June 2018 20

Figure 24. Contractor's camp at Powerhouse area.

Explosive

Approval for the procurement, supply, storage of explosives and blasting works have been received from the Ministry of Defense, Ministry of Energy and Ministry of Foreign Affairs. Construction of Storage Bunker at Site is complete near Bhorleni camp. Army has started operating from the camp since May 2018. View of army camp and explosive bunker is shown in Figure 25 and Figure 26.

Figure 25. Bunker near Surge Tunnel Area

Figure 26. Army Camp near Surge Tunnel area.

Civil Works 5.3.1 General

Total civil works is sub-divided into surface and underground structures. Surface structures include the weir, intake, gravel trap, approach canal, settling basin, powerhouse and switchyard whereas headrace tunnel, surge shaft and penstock shaft lies in underground structures.


June 2018 21

5.3.2 Surface Structures

Headworks

The diversion weir is a gravity weir of 31.8 m long crest with horizontal floor stilling basin. The weir crest is fixed at 1262.0 masl and invert level of intake at 1258.0 masl to divert the design discharge of 17.05 m3/sec with additional 15% for gravel trap and settling basin flushing. The head over the weir crest during 1 in 100 years flood, which is equivalent to 475.0 m3/s, is calculated to be about 3.6 m, which means that the maximum water level will be at 1264.10 masl considering the one undersluice gate opening. A low head bed load sluicers one gate and three undersluicers are proposed on the left side of the diversion weir beside intake for conventional hydraulic flushing of bed load.

RCC side intake is proposed as the submerged orifice type intake, located immediately upstream and adjacent to the bed load sluice to withdraw the design discharge of 17.05 m3/s including the discharge for the flushing. The invert level of the intake is fixed at 1258.0 masl that the boulder up to 300 mm is allowed to enter through the trash rack of intake and can be flushed back to the river downstream through gravel trap flushing. The intake will have 3 orifices each 4.0 m high and 2.3 m wide. In front of the intake opening, a coarse trash rack of 300 mm c/c passage gap is placed which covers the span for two openings.

Three hopper shaped gravel trap of 5.0 m width and 5.0 m height each is provided immediately after intake chamber to trap coarse particles of size greater than 5 mm. The slope of hopper along the profile starts from 1 m D/S of inlet gate. Immediately after gravel trap, three individual approach culverts having different length, horizontal bends and slopes are provided to carry the design discharge up to the settling basin. The shape of the culvert is square with dimension 2.6 m * 2.6 m.

A hopper type buried settling basin with three chambers is proposed on the left bank of Solu Khola. Each chamber is 85 m long, 9.0 m wide with effective depth of 4.0 m. To collect water from kholsi, drainage arrangement has been made at the hill side. The water from kholsi in the main settling area is collected through cascade drop which diverts water to D/S and U/S side by earth fill slope to the main drain canal. It is a trapezoidal concrete channel of base width 2.5 m and height 1.75m designed to carry the discharge of 15.21 m3/s. Mechanical flushing is proposed for flushing.

5.3.3 Powerhouse

The proposed powerhouse is located at rock on the right bank of the Dudh Koshi few meters

above the high flood level of the 100 years return period. The elevation of the powerhouse was fixed such that it is free from the risk of flooding at the Dudh Koshi River during the monsoon season. To ensure safety, flood protection wall near the powerhouse is also designed along the right bank of Dudh Koshi River. The powerhouse is 60.0 m long, 16.2 m wide and 18.0 m high with reinforced concrete structural elements in the main building with shear walls, brick walls, aluminum composite panels (ACP) and CGI sheet roofing.


June 2018 22

A 70.0 m long tailrace culvert with sectional dimension 2.00 m wide and 1.90 m high for separate unit, 4.60 m wide and 1.9 m high for combined unit and 3.55 m wide and 1.9 m high for section between first and last merge point will pass the design discharge to the Dudh Koshi river at right bank of the river.

5.3.4 Underground Structures

Headrace tunnel has been proposed as a low pressure tunnel from the surface settling basin to the surge tank. The total length of the headrace tunnel is 4503.0 m. An Adit tunnel of 98 m length is proposed at 200m downstream from the inlet portal. Similarly, outlet Adit tunnel is proposed before the surge tunnel. Headrace tunnel has been proposed as a low pressure tunnel from the surface settling basin to the surge tank. However, the size of the tunnel is taken as 4m width and 4.25 m height considering the required height for the vehicle movement and for the provision of the ventilation.

The dimension of surge tunnel is 4.0 x 4.0 m with a slope length of 375.0m. The surge analysis shows the maximum surge level is 1272.28masl and minimum level of down surge level as 1246.78masl.

5.3.5 Headrace Tunnel

Inlet Portal which is after the power culvert is the main entrance for the conveyance of water to the headrace tunnel. Inverted D shaped tunnel with width of 4.0 m x 4.25 m finished diameter shall be the main part of the water conveyance system. Figure 27, Figure 28 shows the tunnel progress at headrace tunnel from inlet.

Figure 27. Shotcrete work at Inlet Portal. Figure 28. Drilling at headrace tunnel using Boomer.

5.3.6 Adit Tunnels

i) Adit 2, 2.1 and 2.2

The new location of Adit 2 lies in the 400m downstream of the previous Adit-2. This Adit now facilitates the construction of vertical shafts. Two new Adits ie. Adit 2.1 and 2.2 has been incorporated to expedite the headrace tunnel excavation. The EPC contractor has completed


June 2018 23

the portal preparation of Adit 2.1 and excavation of the tunnel is ongoing. Figure 29 Figure 30 and Figure 31 shows the location and the tunnel work at Adit 2.1.

Figure 29. Revised Adit 2 map

Figure 30. Shotcreting work at Adit 2.1.

ii) Adit 4

Adit 4 located near powerhouse is of length 300 m and of internal size 3.8 m inverted D shape. Portal preparation is completed and the EPC contractor is currently excavating the tunnel of Adit 4. Till the end of May 2018, 48 m excavation has been completed. Figure 32, Figure 33 shows the progress at Adit 4.

Figure 31. Adit tunnel Progress


June 2018 24

The summary of tunnel excavation progress till the end of May 2018 at Adit tunnels and headrace tunnel is shown in the below bar diagram.

Adit 2.1 Adit 4

Total length (m) 30 300

completed till the end of May (m) 17 48

0

100

200

300

400

Tunnel excavation Progress at Adit

completed till the end of May (m) Total length (m)

Total length (m) 4503

completed till the end of May (m) 10.5

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

Tunnel excavation Progress at HRT

completed till the end of May (m) Total length (m)

Figure 32. Geological investigation at Adit 4. Figure 33. Adit 4 Progress.


June 2018 25

Chapter 6 Mechanical and Electrical Works

Hydro-Mechanical Works

The penstock pipe is used to convey the water from surge shaft to the turbine. It is an underground structure. The pipe is provided with the horizontal and vertical tunnel shaft of diameter 3.8 m and 3.5 m respectively. The penstock pipe diameter varies from 2.5 m to 2.1 m and finally 1.2 m at the portion of main inlet valve. Likewise, the thickness of the penstock pipe varies from 10 mm to 44 mm. The penstock pipe starts after the surge tunnel with an invert level of 1229.08 having horizontal portion of 276 m length and first vertical drop of 185 m length. Likewise, the pipe passes through the inclined portion of 489 m length, and second vertical drop of 255 m length. After second vertical drop, it runs through an inclined portion of 671 m length up to trifurcation. The penstock pipe has varying diameter with varying thickness. Altogether, the penstock alignment has four bends before trifurcation. The vertical part is penstock casing with concrete infill and the horizontal part has the support piers at 8 m c/c spacing as shown in the drawings. There are two Adits: one at the location of second drop shaft and another from the powerhouse site to ease the construction of the penstock pipe.

Electro-Mechanical Works

Considering the head and flow available, calculated number of jets, so as to achieve maximum efficiency with the jet ratio of 12.21 was found to be six (6). The overall design has been based on four (4) numbers of jets. Pelton turbine with vertical shaft alignment was selected. The elevation of the turbine axis was set at 647.30 masl. Total no. of turbines is 3 with a capacity of 30400 KW each assuming the efficiency to be 91%.

Transmission Facilities Power from the powerhouse is evacuated to Lamane, Tingla sub-station through 132 kV double circuit transmission line of about 12 km length, from where it is connected to the national grid.

After the study and data collection required IEE draft report has been submitted to DOED.


June 2018 26

Chapter 7 Social Works

The project has been doing different social activities in project affected areas. One of the major social activity in this period was upgradation of village road from Ramite to Surge tank of LSHEP (2.5km) on the request of public. The upgradation of Ramite road is shown in Figure 34 and Figure 35. Beside that the maintenance of village road from Tumse to Panchan is being done. Village road at Maikhubesi to old suspension bridge was also upgraded on the request of local people. The recent activities on the different sections of the social road are listed in Table 10.

Figure 34. Road extension work at Ramite Figure 35. Social Road upgradation work

Table 10. List of Road constructed for society

S. N.

Road Description Total length (km) Work Executed

1. Ramite to Surge tank of LSHEP (82mw)

2.5 Widening and upgrading (90% complete)

2. Maikhubesi to old suspension bridge 0.7 Upgrading

3. Tumse to Panchan 9.3 Widening and maintenance

4. Rolim Road 6 New Track opening

5.. Road to Salyan from Thuldhunga 2.5 Widening and maintenance

6. Village Road at Baspura 2 Widening and maintenance

7. Village Road at Bhorleni 1.6 New Track opening

Similarly, a water tank of 1000 ltrs capacity has been constructed at Bhorleni on the request of local people. Excavator and JCB has also been used for various social purpose at Panchan and Tingla area.


June 2018 27

Except for road construction, Sahas Urja is also helping locals with temple construction. This company also provided computers to schools and provided stretchers to the then Panchan VDC.

Vocational trainings of electrician and off-season vegetable farming was provided to the locals from 19th March 2018 to 18th April 2018. The training was held at two locations i.e. Salyan and Panchan. A total of 109 participants attended the training program. Figure 36 to Figure 41.

Figure 36. Inauguration of Training Program

Figure 37. Program coordinator with Trainers

Figure 38. Participants of off-season farming

Figure 39. Participants working in the field

Figure 40. Participants receiving certificate

Figure 41. Group picture after certificate distribution


June 2018 28

Annex:1 Some Additional Photos

Figure 42. New headworks design after modification

Figure 43. Modified headworks design with three settling basin

Figure 44. Meeting with CMC and FIH at site office.

Figure 45. Site Visit of technical team.

Figure 47. Fencing work at army camp area. Figure 46. Container being transported at powerhouse.


June 2018 29

Figure 48. Site preparation for labour camp and batching plant.

Figure 49. Camp at Headworks area.

Figure 50. Bridge 2 installation progress.

Figure 51. Bailey Bridge 2

Figure 52. Contractor's equipment at site.

Figure 53. Expatriate camp at Headworks


June 2018 30

Figure 56. Metal works at site.

Figure 57. View of Adit Tunnel.

Figure 55. Adit 2.1 tunnel progress

Figure 59. Sample of rock during Geological investigation at Adit 3

Figure 58. Geological investigation at Adit 3 area.

Figure 54. Adit 2.1 Portal preparation.


June 2018 31

Figure 60. Safety signals at site.

Figure 61. Adit 2.1.

Figure 62. Access Road

Figure 65. Social Road upgraded by Sahas Urja Ltd.

Figure 63. Boulder Riprap at Maikhu Kholsi.

Figure 64. Retaining wall at Ramite road.

solu khola (dudh koshi) hydroelectric project...

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