GOVERNMENT OF NEPAL DEPARTMENT OF …cfgorrp.dhm.gov.np/wp-content/uploads/2016/03/Final-Report-DHM_31... · department of hydrology & meteorology community based flood and glacier

GOVERNMENT OF NEPAL DEPARTMENT OF HYDROLOGY & METEOROLOGY

COMMUNITY BASED FLOOD AND GLACIER LAKE OUTBURST RISK REDUCTION PROJECT (CFGORRP)

BABARMAHAL, KATHMANDU

Submitted by:

Cegelec Engineering Pvt. Ltd.

Buddha Nagar-P.O. Box. No. 13138-Kathmandu

Email:[email protected]

(Tell)+977 4780811

Final Report to

Validation of Detail Design

Report to Sediment, Flood

Proofing Drainage System

under Component II of the

CFGORRP

July 2014

4 Terai districts ( Mahottari, Siraha, Saptari and Udayapur)

Final Report of Validation of Detail Design Report to Sediment, Flood Proofing Drainage System under Component II of the CFGORRP

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Table of Contents List of Table ........................................................................................................................................ iii

List of Figure ....................................................................................................................................... iii

1. Introduction .......................................................................................................................... 1

1.1 Background ................................................................................................................................... 1

1.2 Objectives ..................................................................................................................................... 2

1.3 Scope of the work ......................................................................................................................... 2

2. Methodology ......................................................................................................................... 3

2.1 Preparation of Checklists, Questionnaires and Formats ................................................................ 3

2.2 Field Work .................................................................................................................................... 4

2.3VDRMC Meetings ......................................................................................................................... 4

3. Field Verification of ETW, FPDS and EC ......................................................................... 6

3.1 Verification and Prioritization of ETW and Sanitation ................................................................. 6

3.1.1 Siraha District ........................................................................................................................ 6

3.1.2 Saptari District ....................................................................................................................... 8

3.1.3 Udayapur District ................................................................................................................... 9

3.1.4 Mahotari District .................................................................................................................. 10

3.2Verification of Rehabilitation of Flood Proofing Drainage System (FPDS) ............................... 10

3.2.1Siraha District ....................................................................................................................... 12

3.2.2 Saptari District ..................................................................................................................... 13

3.2.3 Udayapur District ................................................................................................................. 14

3.2.4Mahottari District .................................................................................................................. 15

3.3Verification of Evacuation Centre and Location.......................................................................... 15

4. Sediment Control ............................................................................................................... 16

4.1Structural Measures for watershed Management ......................................................................... 16

4.1.1 Gagan River ......................................................................................................................... 16

4.1.2 Khando River ....................................................................................................................... 19

4.1.3 Hadiya and Kong River ........................................................................................................ 21

4.1.4Ratu River ............................................................................................................................. 24

5. Cost Estimate of Prioritized Embankment & Bio-engineering ..................................... 29

5.1 Unit Rate ..................................................................................................................................... 29

5.2 Cost of Prioritized hot spot section for first phase implementation ............................................ 29

6. Non-structural Measures ................................................................................................... 31

6.1 Bioengineering ............................................................................................................................ 31

7. Photographs: ...................................................................................................................... 34


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Appendix ........................................................................................................................................... 37

Appendix 1: Elevated Tube well, West Water Drain around ETW in study report and Field

Verification ................................................................................................................................... 38

Appendix 2: Rehabilitation of Flood Proofing Drainage system (FPDS) along Access Road in

study report and Field Verification ............................................................................................... 39

Appendix 3: Evacuation centers (EC) proposed in study report and Field Verification ............... 40

Appendix 4: Structural Measure: Embankments Proposed in study report and Field Verification

...................................................................................................................................................... 41

Appendix 5: Structural Measure: Spur Proposed in study report and Field Verification ............. 42

Appendix 6: Cost Estimate of River embankment, Spur and Bioengineering in study report and

Field Verification .......................................................................................................................... 43

Appendix 7: Cost of Bio-engineering ........................................................................................... 44


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List of Table Table 1: Study VDCs, River Basin and VDRMC meeting date and field verification date ................................... 5

Table 2: Field Verified Tube well location and west water drain around Tube Well in Siraha .............................. 7

Table 3: Field Verified Tube well location and west water drain around Tube Well in Saptari ............................. 8

Table 4: Field Verified Tube well location and west water drain around Tube Well in Udayapur ........................ 9

Table 5: Field Verified Tube well location and west water Drain around Tube Well in Mahotari ...................... 10

Table 6: Rehabilitation of FPDS verified along the access roads in Tulsipur& PipraPra Pi VDCs ..................... 12

Table 7: Rehabilitation of FPDS verified along the access roads in Pakari & Dighawa VDCs ........................... 13

Table 8: Rehabilitation of FPDS verified along the access roads in Hadiya & Jogidaha VDCs .......................... 14

Table 9: Rehabilitation of FPDS verified along the access roads in Nahini & Sarpallo VDCs ........................... 15

Table 10: Proposed EC site location and Field verified Evacuation Centre in districts ....................................... 16

Table 11: Field verified length and location for earthen embankment in Gagan river ......................................... 17

Table 12: Prioritized hotspot for construction of earthen embankment & Bio-engineering in Gagan River ........ 18

Table 13: Field verified length and location for earthen embankment in Khando River ...................................... 19 Table 14: Table 14: Prioritized hotspot for construction of earthen embankment & Bio-engineering in Khando

River ............................................................................................................................................................ 20

Table 15: Field verified length for earthen embankment and location in Kong and Hadiya river ........................ 22 Table 16: Prioritized hotspot for construction of earthen embankment & Bio-engineering in Kong & Hadiya

River ............................................................................................................................................................ 23

Table 17: Field verified length and location of Gabion Spur in Ratu River ......................................................... 26 Table 18: Field Verified length, location for earthen embankment in Ratu and Ankushi River in Sarpallo VDC

..................................................................................................................................................................... 27 Table 19: Field Verified length, location for earthen embankment in Ratu and Ankushi River in Sarpallo VDC

..................................................................................................................................................................... 28

Table 20: Summary of embankment cost including Bio-engineering study period cost, Field Verified cost ....... 29

Table 21: Field verified list of Plants, species with their use for bioengineering ................................................. 31

List of Figure Figure 1: Verification of location of ETW in Pakari and ETW drain length measured in Nahini VDC ............... 4

Figure 2: VDRMC meeting in Mahottari, Sirah, & Udayapur ............................................................................... 5

Figure 3: Existing drain in Jogidaha and Nahini Mahottari ................................................................................ 12

Figure 5: Location of Earthen Embankment in Gagan River ............................................................................... 18

Figure 6: Sediment deposition and Bank cutting in Khando River....................................................................... 19

Figure 8: Proposed embankment and existing river training work in Kong River ............................................... 21

Figure 9: Location of Earthen Embankment in Kong River ................................................................................. 23

Figure 10: Location of Proposed Embankment in Hadiya River ......................................................................... 24

Figure 11: Proposed location of Spur and embankment in Ratu River ................................................................ 25

Figure 12: Ratu River Left bank cutting about 3+000 area ................................................................................. 25

Figure 13: Locations of Proposed Spur and Embankment in Ratu River in Mahotari ......................................... 26

Figure 14: Ratu river approaching towards farm land and bank cutting ............................................................ 27

Figure 15: Proposed embankment site in Ankusi & Jangahariver U/S of Bajharang chowk ............................... 27

Figure 16: Locations of Earthen Embankment in Ankush and Jangaha in Sarpolla, Mahatari ........................... 28


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1. Introduction

1.1 Background

Community Based Flood and Glacial Lake Outburst Risk Reduction Project (CFGORRP) is a joint

program undertaking of the Government of Nepal (GoN), Global Environment Facility (GEF) and

the United Nations Development Programee (UNDP). The project is being implemented by the

Department of Hydrology and Meteorology (DHM) under the Ministry of Science, Technology

and Environment (MoSTE) as the lead Implementing Agency. The project has two components:

component I focuses on the GLOF risk reduction from Imja Lake and the Component II is about

the flood risk management in four Terai districts through structural and non-structural measures,

preparedness activities, capacity building etc.

CFGORRP under component II has an objective to reduce human and material losses from

recurrent flooding events in four flood prone districts of Terai and will have increased adaptive

capacity of local communities in eight study VDCs through locally appropriate structural and non–

structural measures, a sediment control programme, river bank, and slope stabilization and the

implementation of CBEWS.

The project covered watersheds (Ratu, Khando, Gagan, Hadiya/Kong) are originated from Churia

hills. The river channels originated from Churia hills in the Terai are also unstable leading to

prolonged inundation, damage to river banks causing bank erosion and sediment deposits in the

farmlands. Due to concentrated rainfall during monsoon, fragile/rugged and unstable land natures

of Churia region, Churia originating rivers are responsible for intensive soil erosion, landslides,

flash floods, and ultimately massive sedimentation in Terai. The sediments deposition on flat lands

blocks the waterways which results several meandering of the river. Many people are displaced,

and hundreds of hectares of lands are wasted. The selected VDCs of the four districts (Mahottari,

Saptari, Siraha, and Udayapur) lie in the Terai Region (low lying flat zone) and being affected

every year by flood and sediment deposition in the fertile land resulting in to loss of property, land,

and human lives.

The Community Based Flood and Glacial Lake Outburst Risk Reduction Project (CFGORRP) has

recently received the Final Report of two studies from the respective service providers. The report

has highlighted need of project related various activities (i.e. slope stabilization, watershed

management, elevated tube wells and flood proofing drainage systems) in the project area.

Technical design, dimensions, location, quantity and cost estimates of these components as well

as project prioritization based on vulnerability assessment are the main theme of the studies.

However, their validation is important in the final decision making process because validation

ensures that the dimensions, and locations of the project components are properly checked.

This is the final report prepared and submitted to CFGORRP in accordance with the contract

between CFGORRP/DHM (hereinafter referred as Client) and Cegelec Engineering Pvt. Ltd

(hereafter referred as consultant) to carry out the validation and verification of Detail Design Study

related to (i) Sediment Control and Stabilization of Hazard–prone Slope & River Banks through

Structural and Non-Structural Mechanism and (ii) Flood Proofing of Water and Sanitation Systems


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in Sarpallo and Nainhi in Ratu Watershed (Mahottari), Tulsipur and Pipra Pra Pi in Gagan

Watershed (Siraha), Dighawa and Pakari in Khando Watershed (Saptari) and Hadiya and Jogidaha

in Triyuga Watershed (Udayapur) and hired a monitoring expert to conduct validation of Study

Reports as per ToR.

The consultant has completed all the assigned work as mentioned in the ToR which includes

Submitted Inception Report

Completed field verification work

Prepared and Submitted Draft Report

Presented Findings of the Draft Report

1.2 Objectives

The main objective of the assignment is to validate project components proposed in the study 1

and 2. The specific objectives of the assignment are

To validate requirement of all structural measures proposed in study 1 in terms of location and

dimension in the actual field condition

To ground verify bio-engineering species proposed in the study 1 with regard to availability,

quantity, costing etc. for each project area (i.e. VDC and community)

To confirm the information provided for the watershed management plan in the project area

under study 1 through ground verification

To validate the proposed elevated tube wells in the most vulnerability communities of the 8

selected VDCs in terms of location and length of screen made in the study 2 with respect to

actual field condition

To conduct ground verification of the flood proofing drainage system in terms of length,

location, cross-section etc. proposed in the study 2

To validate the prioritized activities proposed in the studies 1 and 2.

1.3 Scope of the work

The scope of the work are listed below

Undertake a thorough study of task 1 and 2 prior to field mobilization, prepare necessary check

lists and prepare and submit inception report

Verify and validate all structural and non-structural measures proposed in design study in terms

of their location and dimension in field.

Confirm the available information provided by the study reports for undertaking the watershed

management interventions/ plan under study area

Validate and confirm the proposed elevated tube wells for the most vulnerable communities of

the 8 selected VDCs in terms of their location, and prioritized under study 2 with respect to

actual field locations and conditions.

Verify the major hotspots and prioritize their best conservation measures and location.

Share with community member, ground truth and verify the bio-engineering species proposed

in the study areas with regard to availability, quantity etc. for each project area.


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Undertake ground verification of the flood proofing drainage system in terms of length,

location, section etc.

Visit the proposed site with VDRMC member, DPO for spot verification and clarify all the

related issues (if any) and validated the technical and social data.

Compile the field verified data of sediment control, watershed management and list out the

best vegetative and engineering measures for flood and soil erosion control on different

locations of the river systems.

Based on the above field assessment and verification, prepare a draft report of the study

findings for presentation to PMU/DHM and partners for soliciting comments and feedbacks.

2. Methodology

The Consultant reviewed the Terms of Reference (ToR) provided by the CFGORRP/DHM and

prepared checklist and formats to conduct field verification of Elevated Tube Well (ETWs) for

safe water supply in inundation prone areas, finalization of location of proposed ETW, Evacuation

Centre and sanitation, measured length of drain for drain out water from ETW to near

drain/Pokhari, verified design data of flood proofing drainage systems in 4 Terai districts (8 VDCs)

and verification of river training structure and non-structural parameter.

In each district, study data were checked and verified in close coordination with VDRMC and

vulnerable communities. The VDC secretaries of all VDCs were contacted during validation of

design data and confirm in field using checklist. Basically the validation work was divided into

three parts, (i) validation of ETW location, ranking and prioritization, (ii) validation of flood

proofing drainage system and (iii) validation of sediment control measures (location, dimension &

prioritization). The draft report was prepared and submitted and final report has now been prepared

and submitted after incorporating comments, and feedbacks made in the draft report and

presentation.

2.1 Preparation of Checklists, Questionnaires and Formats

Checklists for field verification survey were prepared during the inception reporting phase to cover

sediment control measures, ETW and Flood Proofing Drainage System (FPDS).The Checklists,

questionnaires and formats were prepared for field verification for which the consultant paid

attention on the following issues:

Confirmation of the site for flood proofing drainage system & access to drinking water

supplies communities in 8 VDCs of 4 Terai districts with consultation of community,

VDRMC, DPO.

Checklist for verification of structural measures proposed in the study in terms of size,

requirement, adequacy and location.

Study, validate and confirm the plan proposed in the study report with understanding

of watershed management in Ratu, Hadiya, Kong, Gagan and Khando River.


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Confirm the location and site of proposed structures for sediment control

Verify and confirm whether the proposed Evacuation Centre is required or not and

finalize the location shearing with VDRMC and community member.

2.2 Field Work

After the study of design report and preparation of filed plan and checklists, the Consultant

proceeded to the field. The consultant (individual expert) had visited FCO office Lahan and

finalized the visit plan. The expert visited all four districts with DPOs to verify the proposed ETWs,

FPDS and sediment control measures.

The consultant undertook site specific measurement (size, length, location) using measuring tape

and handled GPS to validate the proposed project data and location. With the help of checklist,

questionnaires, the field data were collected jointly with VDRMC member, community members,

and DPOs. The consultant prioritized the ETW, Sediment Control Measures and FPDS sites during

VDRMC meeting and considering field condition.

Figure 1: Verification of location of ETW in Pakari and ETW drain length measured in Nahini VDC

2.3VDRMC Meetings

The VDRMC consultative meeting is exceedingly important part of the current assignment and

VDRMC meeting was conducted in all the VDCs in the respective VDC buildings facilitated by

the CFGORRP’s DPOs The prioritized ETW, sediment control measures, FPDS were verified in

site and recorded in minutes of meeting. After VDRMC meeting, the consultant, VDRMC

members and respective DPO jointly inspected, measured and verified the sites of proposed

sediment control measures, ETW, flood proofing drainage system.


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Figure 2: VDRMC meeting in Mahottari, Sirah, & Udayapur

Data of aggradations/degradation, inundation, breaching of bank were verified in 8 VDCs of four

flood prone districts. In case of Ratu River, numerous sections along the river stretches were visited

and consultations and interaction were conducted in Nahini, Sarpallo and other VDCs upstream of

East West Highway (Garuribas, Tulsi) adjoining to the river system. The VDRMC meeting and

field verification date is given in the Table 1.

Table 1: Study VDCs, River Basin and VDRMC meeting date and field verification date

SN Districts River VDCs VDRMC meeting and field

Verification date

1 Siraha Gagan Tulsipur, PipraPra Pi 08 &09 June 014

2 Saptari Khando Dighawa, Pakari 10 & 11 June 014

3 Udayapur Hadiya,

Kong

Hadiya, Jogidaha 12 & 13 June 014

4 Mahottari Ratu River Sarpallo, Nainhi and River System

North to east-west highway (Gauribas

and Tulsi)

14 & 15 June 014


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3. Field Verification of ETW, FPDS and EC

Field verification to confirm the designed location of the Elevated Tube Well (ETW), Flood

Proofing Drainage System (FPDS), Evacuation Centre (EC) and Sediment Control Measures in

eight VDCs, and five river basins were carried out in coordination and consultation with DPO,

VDRMC members and other communities. The field verification was basically divided in four

parts and carried out rigorously in field which basically covered;

Verification of Elevated Tube Well, Drainage and Sanitation system,

Verification of Flood Proofing Drainage System along Access Road

Verification of Evacuation Centre, and

Verification of watershed management, disaster prone areas and hotspots.

3.1 Verification and Prioritization of ETW and Sanitation

The verification and prioritization of ETW was carried out in each VDC based on vulnerability

ranking of the communities, impacts of flooding to the communities, proximity to flood hazard.

These sites were jointly visited in actual field and discussed in the VDRMC meeting. The

prioritization was done in actual field based situation and position. Entire communities are

classified into three groups; such as high vulnerable (H), medium vulnerable (M) and low

vulnerable (L). In Siraha, Saptari, and Mahottari districts, the under-privileged Dalits such as the

Mushar and Chamars, and the Janajaatis in Udaypur who were ranked as excluded groups have

got high priority. Similarly, landless and disabled people also received highest priority for ETW.

The Dalit, Mushar and Chamars and Janajati and landless people and those who lives near river

bank and high inundation and are directly affected by floods are preferred high vulnerable

communities.

Medium level priority was applied to those communities where the effect of flood is minimal, such

as large open areas, comparatively wealthier villagers with abundant land, less inundation, and

higher literacy. Accordingly these were ranked and prioritized during verification.

In ensuring proper drainage system around the proposed ETWs, provisions of either pipe and/or

open drains are made and the lengths of such drainage systems were measured during field

verification. However in case of non-availability of land and local drains near tube well locations,

construction of soak pits was proposed and verified the soak pit for implementation.

3.1.1 Siraha District

Tulsipur and PipraPra Pi fall in high vulnerable community in Gagan. The list of prioritized ETWs

and their rank, type and length of drain around ETW has presented in table below after verification

in the field and interaction with the local community at VDRMC meeting.


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Table 2: Field Verified Tube well location and west water drain around Tube Well in Siraha

District VDC

Field Verified (FV) ETW and west water drain

Name of community

to construct ETW

Ward

no

Type of

ETW

Rank/Pri

ority

Length

(m) of

Drain

Remarks

Siraha

Tulsip

ur

ChamarTole 1 1-ii High/5 6 Soak pit

BaniniyaTole 2 1-ii High/1 80 At Pokhari

BaluTole 5 3-ii High/2 20 Drain

Ramjankitole 6 1-ii Medium/1 15 Soak pit

ChamarTole 7 1-ii High/3 9 Soak pit

Ramjankitole 7&6 Omitted

Mandaltole (Khatbe) 4 1-ii High/4 34 Drain

PipraP

ra Pi

KadarhawaTole 3 1-ii High/4 10 NaiakPokhari

Drain

KadarhawaTole 2 1-ii High/2 15 Soak pit

KadarhawaTole 2 1-ii High/5 15 Soak pit

KadarhawaTole 1 1-ii Medium/2 8 MahadavMa

tha, Drain

Jamuwatole,Musar

(Dalit)

6 1-ii High/1 10 near

Jamuwapok

hari

JamuwaRamjanakitole 6 1-ii Omitted

Khajanpurtole

(RamjanakiMandir)

7 1-ii Medium/4 15 Canal

Chamartole 7 1-ii Medium/3 15 Soak pit

Khajanpurtole 9 1-ii Medium/5 30 Drain

Khajanpurtole 8 1-ii Medium/6 20 Drain

Chamartole 4 1-ii High/3 20 Drain

Paschimbaritole 5 1-ii Medium/1 12 Drain

334

There were altogether 7 ETWs proposed in the study report in Tulsipur VDC out of which, 5 got

high priority (H), one medium and the rest 1was omitted. The discarded ETW was proposed at

Ram Janaki Tole 7& 6 but it was noticed inappropriate in terms of location and does not meet the

requirement of ETW. The ETW proposed in Ram Janaki Tole (ward 6) and Chamar Tole (ward 7)

mostly covered the same community and ETW in Ram Janki tole (ward 6 &7) was proposed in

border of ward 6 & 7 and the proposed land owner oppose to provide the land. Similarly in Pipra

Pra Pi VDC, out of 12 proposed ETWs; 5 falls in high priority, 6 in medium (M) and one ETW

proposed in Jamuwa Ramjanaki Tole (ward 6) was discarded as the ETW proposed in Jamuwa

Ramjanakitole (ward 6) of Pipra Pra Pi VDC has also been proposed in debatable location of same

ward 6 and it is significantly far away from the vulnerable communities and does not necessarily

serve them at the time of inundation.

The drainage length from ETW to the nearest possible outlet was verified in field. The length of

drain measured to drain out the ETW waste water was measured to be 164 m. and 170 m. in


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Tulsipur and Pipra Pra Pi against the proposed lengths of 142 m and 205 m respectively. A

comparison between proposed and field verified lengths of waste water with regard to location,

ward, and length of proposed drain around ETW is presented in Appendix1.

3.1.2 Saptari District

The Pakari and Diguwa VDCs are highly vulnerable areas in the Khando River basin because of

prolonged inundation, sediment deposition in the agricultural land, bank cutting along river

corridor in the VDCs. The study report has proposed 7 ETWs in Pakari VDCs which were split up

as 4 under high priority, 2 medium and 1 low priorities. All ETWs were field verified as correctly

proposed in terms of location and community to be served. Four ETWs were prioritized as high, 1

as medium and the rest 1 as low totaling of 6 proposed and verified in Dighwa VDC. Table 3

shows the field verified ETWs in Pakari and Dighwa under different priorities as mentioned.

Table 3: Field Verified Tube well location and west water drain around Tube Well in Saptari

District VDC


Name of community

to construct ETW

Ward

no

Type

of

ETW

Rank/Priority

Length

(m) of

Drain

Remarks

Saptari

Pakari

Pakaritole 5 1-iii Medium/2 20 Drain

Chamartole,Ramtole 4 2-iii High/1 20 Drain

Devsthaltole 3 3-iii Medium/1 20 Drain

Musslimtole,

JumiMasjit

3 2-iii High/3 55 Drain

Musharitole 4 1-iii High/2 15 Soak pit

Musaharitole, Ra-

PraVidalaya

2 1-iii Low/1 16 Drain

Sonahara (Musahar)

tole


Dighwa

Musahar (Sada)tole,

ChiyaChowk

9 1-iii High/4 15 Soak pit

Ram Chamar&

Yadav tole


Khang/Yadav tole 5 2-iii High/3 15 Soak pit

Diguwa (Mandal&

Yadav)

8 1-iii Medium/1 15 Drain

Rampur (Mushar)/

Sadhatole


BirolBazzarChowk 1,2&

3

1-iii Low/1 15 Soak pit

320

The length of waste water drain around proposed ETW has also been verified. The drainage length

verified in Pakari and Dighawa was about 183 and 137 m, respectively. Whereas the study has

estimated 162 and 140 m respectively. The detail comparison of length and location is presented

in Appendix 1 of this report.


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3.1.3 Udayapur District

Hadiya and Jogidaha VDCs are identified as highly vulnerable communities respectively in Hadiya

and Kong River watersheds. There are 7 vulnerable human settlements spread in 4 wards of

Hadiya. Similarly, in Jogidaha VDC, four settlements in 5 wards have been identified as vulnerable

communities. The sites of designed ETWs were verified in terms of location of ETW, ranking and

length of waste water drain from ETW to the nearest possible outlet and are presented in table 4

in below.

Table 4: Field Verified Tube Well Location and Waste Water Drain around Tube Well in Udayapur

District VDC


Name of community to

construct ETW

Ward

no

Type of

ETW

Rank/Priori

ty

Length

(m) of

Drain

Remarks

Udayapur

Hadiya

Dhimkitole,umal,B.K

Basti

5 1-i High/2 15

Soak pit

Dungaha Dhar

(Musartole)

5 1-i High/1 15

Soak pit

Rajajitole 5 1-i Low/2 15 Soak pit

Bakainiyatole 7 1-i Medium/1 28 Drain

Ramjanakitole 6 1-i Medium/2 50 Drain

Khoriyatole 6 2-i High/3 38 Drain

DevnagarNayaBastitole 7 1-i Medium/4 25 Drain

BhimaTole 2 3-i Medium/3 10 Drain

Devdhartole 1 1-i Low/1 15 Soak pit

Jogidaha

Dachhintole, near Pokhari 3 1-i High/1 12 Drain

Khudiyahitole 3 1-i Medium/1 15 Drain

Nayabasti (Mushar) tole 7 2-i High/2 15 Soak pit

Baluwaitole 5 1-i High/4 15 Soak pit

VDC land Jogidaha 6 1-i Low/1 15 Soak pit

UttarbariTole 2 1-i High/3 15 Soak pit

Total 298

Out of the 9 numbers of ETW designed in Hadiya VDC, 3 are ranked as high priority (H), 4

medium and the rest 2 low priority. Similarly in Jogidaha VDC, out of 6 ETWs proposed in study,

4 are highly (H) prioritized, 1 medium (M) and one in low priority. The measured lengths of the

drainage were 211 m and 87 m in Hadiya and Jogidaha respectively, whereas the proposed lengths

were 200 and 88 m respectively indicating that proposed and field verified lengths are nearly same.

The field verified ETW location and drain length for ETW sanitation are presented in Appendix

1.


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3.1.4 Mahotari District

Sarpollo and Nahini are the study areas in Mahottari district under Ratu watershed. Sarpallo is

severely affected by Jangha and Aunsi River, tributaries of Ratu River whereas Nainhi is inundated

by the Ankar River.

All the three ETWs proposed for Naini VDC are under high priority (H) and VDRMC meeting

requested an additional ETW in Nainhi Primary School. Since, the school building is centrally

located and may be used as an evacuation zone at the time of flood, one ETW has now been

recommended for the installation. Similarly, out of three ETW proposed in Sarpallo VDC, 2 fall

in high ranking and one in medium.

Table 5: Field Verified Tube well location and west water Drain around Tube Well in Mahotari

District VDC

Field Verification (FV)

Name of

community to

construct ETW

Ward

no

Type

of

ETW

Rank/P

riority

Length

(m) of

Drain Remarks

Mahotari

Nahini

Chamartole,

Tharuaihai

8 3-iv High/2 10 In Existing Drain

DachhinbariTole,

Tharuaihai

6 1-iv High/3 58 Hume pipe (30 cm) to

cross road to Drain out

MahilbariTole 4 1-iv High/1 30 6” HDP pipe to Drain

Nahinitole 2&3 NahiniPri. School area,

Flood affected. Requested

to add an ETW.

Sarpallo

Bajhranga Chock 5 2-iv Medium

/1

26 River

uttarbariTole 8 1-iv High/1 38 River

JhingasthanTole 9 2-iv High/2 76 Drain

238

The length of drainage around ETW has been verified and length measured in Nahini and Sarpallo

is about 98 and 140 m, where as in design the length was about 93 m and 139 m respectively. The

comparison list of ETW, location, ranking and drainage around ETW are presented in Appendix

1.

3.2Verification of Rehabilitation of Flood Proofing Drainage System (FPDS)

The existing drainage systems are not properly functioning mainly due to lack of inadequate

longitudinal slope gradient in the drain, O&M, inadequate size (10 – 15 cm depth) and lack of fund

for regular operation and maintenance. It was observed that the drains are constructed without

proper side slope along earthen roads resulting in the drains’ side collapse and ultimately causing


11 | P a g e

inundation at the time of floods. Blockage of the drainage is mainly due to siltation and collapses

of the drainage are the main reasons of diminishing the drains’ cross-sectional size. The consultant

with VDRMC and DPO conducted transect walk interacting with community to identify the most

water logging areas for estimation and verification of designed drain length for rehabilitation and

verified the rehabilitation length for FPDS in field.

During discussion, the local communities and VDRMC representatives attempted to assure that

rehabilitation of the existing drainage may minimize the duration and spatial extent of inundation.

There will be no prolonged inundation and the flood level will be reduced after drain out the flood

water through rehabilitated drainage system and also prevent the entry of flood in the communities.

Rehabilitation of the existing drainage system should include recovery of the original shape size,

side slope with proper longitudinal slope so that there would be no inundation.

Siltation and inundations are natural phenomenon in most of the project VDCs because they lie in

the middle Terai plane where groundwater is found shallow and spring line encounters and

affluent/effluent of the flow occurs. In such places water level in the river rises immediately after

the rain starts during monsoon. Basically, most of the cases are similar in Siraha, Saptari, and

Mahottari district. However, in Jogidaha and Hadiya of Udayapur district, it is somehow different.

Tributaries of the Triyuga are Hadiya and Kong which flow from south to north with

approximately 1 to 2% gradient in the terrain and comparatively less inundation occurs. However,

to drain out the flood the rehabilitation of drain has been proposed and verified in field.

VDRMC members and VDC secretaries of Siraha, Saptari and Mohattari shared that most of the

low land and affected area remains inundated for two to three days or more than that depending

upon rainfall duration and extent of flood in the area and the stagnated water is generally drained

out half to one day depending on recession of water level in the corresponding river. The existing

drains along the road sides in the settlements are blocked at most of the places so they need to be

rehabilitated and reconstructed in places where there is no proper drainage system.


12 | P a g e

Figure 3: Existing drain in Jogidaha and Nahini Mahottari

It was noted that about 1/3rd of total drains ns have been blockage in the existing drain per the field

observation and verification, there are about 1/3rd of total length that have been blockages in the

existing drains on the side of the roads and the VDRMC member suggested that after rehabilitation

of existing blocked drains, the rainy water as well as flood water passes towards river through

these drains.

3.2.1Siraha District

The cause of inundation in Tulsipur and Pipra Pra Pi VDC is Gagan River. Most of the vulnerable

communities within Tulshipur are located about 30 to 50 m to the Gagan River bank. Most of the

households within ward 1, 2, 4, 5, 6 and 7 are prone to inundation during floods in Tulsipur. Also

in Pipra Pra Pi VDC, most of the affected wards are 1, 2, and 3, and wards 4, 5, and 6 by Sugawati

River, and wards 7, 8, and 9 are by Sahaja River.

The rehabilitation of flood proofing drainage verified in field is about 635 m in Tulsipur and 1470

m in Pipra Pra Pi VDCs, whereas these figures are about 645 m and 1266 m respectively in the

study report. The summary is presented in table 6 of this report.

Table 6: Rehabilitation of FPDS verified along the access roads in Tulsipur& PipraPra Pi VDCs

Distric

t

VDCs Location of ETW Ward no Ranking

Field Verified

Length (m) (FV)


13 | P a g e

Siraha

Tulsipur

Baniniyatole, ward no 1,2 2 High/1 130

Chamartole, ward no 1 1 High/5 120

Balutole, ward no 5 5 High/2 120

Mandal(khatbe) , ward no 4 4 High/4 80

Ramjanakitole, ward no 6 6 Medium/1 85


Ramjanakitole, ward no 6 & 7 6 & 7 0

Sub total 635

PipraPra

Pi

Karaharbatole(mahadev), ward 1 1 Medium/2 60

Karaharbatole, ward no 3 3 High/4 150

Ramjanakitole, evacuation center 2 High/5 70

Karaharbatole, ward no 3 2 High/2 120

Jabuwa school, ward no 6 6 Omitted

Jamuwatole, ward no 4 6 High/1 240

Chamartole 4 4 High/3 120

Paschimbaritole, ward no 5 5 Medium/1 200

Khajanpurtole, ward no 9 9 Medium/5 120

Khajanpurtole, ward no 8 8 Medium/6 90

Chamartole ward no 7 7 Medium/3 100

Khajanpur, ramjanakitole, ward 7 7 Medium/4 200

Sub-Total 1470

A detailed comparison between study and field verified length of flood proofing drainage is

presented in Appendix 2

3.2.2 Saptari District

Wards 1, 1, 2, 3, 4, and 5 of Pakari and 1,2 5, 7,8 & 9 of Dighwa are being severely affected by

Khado, Mahuwa and Wokado Rivers. Wards 3 and 5 of Pakari are severely affected by the Khando

River. The vulnerable communities are within 30m to 100m from the Khando River, indicating

that the communities are very proximity to flood hazard. The proposed length of flood proofing

drainage to be rehabilitated in study report was 632 m in Dighawa and 662 m in Pakari VDC but

field verified lengths are 765 m and 770 m respectively. The summary of verified length of flood

proofing drainage is presented in the table 7 of this report:

Table 7: Rehabilitation of FPDS verified along the access roads in Pakari & Dighawa VDCs

District VDCs Location of ETW Ward no Ranking

Field Verified

Length (m) (FV)

Saptari Dighawa

Birolebazzar, ward 1,2 1,2&3 Low/1 105

Musahartole, ward 5 9 High/4 150

Mandal and Yadav tole, ward no 8 8 Medium/1 60

Chamar and Yadav tole, ward no 7 7 High/2 60

Kamalpurtole, ward no 5 5 High/3 150

Rampur tole, ward no 9 9 High/1 240


14 | P a g e

Sub total 765

Pakari

Pakaritole,Chamarbasti, ward 4 5 Medium/2 80


Devisthal, ward no 3 3 Medium/1 120

Musslimtole, ward no 3 3 High/3 160

Sonahara(Musahar ) tole, ward 2 2 Low/1 200

Musharitole, ward no 4 4 High/2 80

Sonahara(Musahar ) tole, ward 2 2 High/4 70

Sub total 770

A detailed comparison between the design and field verification length of flood proofing drainage

is presented in Appendix 2

3.2.3 Udayapur District

In Udayapur district, there are several tributaries of the Triyuga rivers and two of them are Hadiya

and Kong which flow from south to north and join Triyuga. Although terrain in both river is

slopping towards the rivers, there is low and flat land in downstream reach of Hadiya and Kong

river indicating that there is a need of FPDS and field verification was also conducted. River banks

in both Hadiya and Kong Rivers are severely eroded and communities located at low flat lands or

near river side are flooded and submerged during peak flood. Jogidaha VDC is mainly affected by

Kong River, Bhadua, and River. Vulnerable communities in wards 2,3,5,7 and 8 are being severely

impacted by the flood and inundation. Moreover, the Kong River joins with the Veduwa River that

helps to intensify the inundation problem in the VDC. The field verified flood proofing drains

slightly went down compared to the study figures because few side drains along the access road

may work as FPDS. The field verified length of FPDS is 1250 in Hadiya and 500 m in Jogidaha

respectively whereas in study, the lengths of FPDS were proposed 2157 m and 652 m respectively

in Hadiya and Jogidaha VDCs. The summaries of field verified FPDS are presented in Table 8.

Table 8: Rehabilitation of FPDS verified along the access roads in Hadiya & Jogidaha VDCs

District VDCs Location of ETW Ward Ranking

Field Verified

Length (m) (FV)

Udayapur

Hadiya

Devdhartole, ward no 1 1 Low/1 150

Bhimatole, ward no 2 2 Medium/3 200

DungahaDhartole (Musar) tole ward 5 5 High/1 150

DhimkiTole, ward no 5 5 High/2 180

RajajiTole, ward no 5 5 Low/2 150

BakainiyaTole, ward no 7 7 Medium/1 150

RamjanakiTole, ward no 6 6 Medium/2 100

KhodiyaTole, ward no 6 6 High/3 120

DevnagarNayaBastiTole, ward 7 7 Medium/4 50

Sub total 1250

Jogidaha Jogidaha VDC - - -


15 | P a g e

Dachhintole, Ward no 3 3 High/1 120

Khudiyahitole, ward no 3 3 Medium/1 80

Uttarbaritole, ward no 2 2 Higgh/3 150

Baluwaitole, ward no 5 5 High/4 150

Nayabasti(Musahar) tole, ward 7 7 High/2 0

VDC land Jogidaha, ward no 6

Sub Total 500

The comparison list of study period and field verified length of flood proofing drainage is in

Appendix 2 of this report.

3.2.4Mahottari District

Nahini VDC is not directly flooding from Ratu, but wards 4, 6 and 8 are mainly affected due to

the irrigation canal that is fed by the floodwater of Ratu; the canal is known as Ankar canal. The

inlet to this canal is about 4 km east from Nahini, in the adjacent of Gonarpuwa VDC in the east

and is closer to the Ratu River. In Sarpallo VDC, the main sources of flooding are the Janga and

Aakusi River (wards 1, 2, and 9), tributaries of Ratu River. FPDS is proposed to drain the flooded

and inundated water from Janga and Aakusi Rivers. The length of FPDS verified in field is about

580 m. and 343 m respectively in Nahini and Sarpallo VDC whereas the proposed in study/or

design phase were 311 and 292 m. respectively. The summary of finding is presented in Table 9.

Table 9: Rehabilitation of FPDS verified along the access roads in Nahini & Sarpallo VDCs

District VDCs Location of ETW Ward

no

Ranking Field Verified

Length (m)

Mahotari

Nahini


Dakshinbaritole, ward no 6 6 High/3 180

Mahilbaritole, ward no 4 4 High/1 200

Sub total 580

Sarpallo

BajhrangChowk, ward no 5 5 Medium/1 100

Uttarbaritole, ward no 8 8 High/1 120

Jhingasthantole, ward no 9 9 High/2 123

Sub total 343

The comparison list of FPDS in study period and field verification is presented in Appendix 2

3.3Verification of Evacuation Centre and Location

Basically elevated open public land could be used as an evacuation zone. In each evacuation zone,

one ETW along with proper sanitation system is proposed, which includes one toilet, septic tank

and soak pit. There is an Evacuation Centre proposed study report in Mahottari (in Bajharang

temple ward 1 & 5 in Sarpallo VDC) and one in Saptari (Birol Bazaar Chowk 1,2&3 in Dighawa

VDC) which are duly verified. The other field verified ECs include one in Ram Janki Tole ward 2

of Pipra Pra Pi VDC and one in VDC building ward 5 of Tulsipur VDC of Siraha, 1 EC has

proposed in Rajaji tole ward 5 of Hadiya VDC and 1 EC in VDC compound ward 6 of Jogidaha


16 | P a g e

VDC in Udayapur. As per field verification, the EC in Udayapur is likely in low priority. However,

the community member and VDRMC members requested for EC in VDC compound in Jogidaha

and Rajaji tole ward 5 in Hadiys VDC. The proposed location and area has verified and confirmed

in site.

Table 10: Proposed EC site location and Field verified Evacuation Centre in districts

Districts VDCs Community War

d

No.

No.

of

ET

Ws

No.

of

Toilet

s

Coordinates HFL EC location

Latitude Longitude (m) From

GL

(degree) (degrees)

Mahotta

ri

Sarpollo BajhrangaCh

owk

1&5 1 1 26.7418 85.7842 1.045 Bajharang

Temple

Nahini

Siraha PipraPra

Pi

RamjanakiT

ole

2 1 1 26.6482 86.3116 0.3 Ramjanakito

le/ Temple

Tulsipur VDC

building,

Tulsipur

5 1 1 0.4

Udayap

ur

Hadiya RajajiTole 5 1 1 26.7813 86.8353 0.3 Rajaji

School

Jogidaha VDC land

Jogidaha

6 1 1 26.7629 86.7698 0.4 VDC Land

Saptari Dighawa BirolBazzar

Chowk

1,2&

3

1 1 26.5581 86.7764 0.4 Birol Market

Pakari

Total 6 6

The detail list of design and field verified Evacuation Centre is presented in Appendix 3

4. Sediment Control

4.1Structural Measures for watershed Management

The consultant visited all five rivers with VDRMC member, community member and DPOs for

verification of location and dimension of proposed spur and embankment. The check lists were

used to collect data and verified location of proposed structural measures. The observation and

verification information are presented in following para.

4.1.1 Gagan River

Bank cutting and deposition of sediment (basically fine particles – sand and silt) in river bed was

observed throughout the Gagan River in project covered VDCs, mostly in downstream of

Banainya. Bank cutting has resulted in meandering of river and high sediment volume and bank

cutting is resulted by the high stream discharge during monsoon and in some cases by insufficient

river channel width. As the river approaches Tulsipur VDC, the bank cutting is severe and

cultivated lands are washed out each year. The photographs presented below show the changes of


17 | P a g e

river course and sediment deposition. Bank cutting and river frequently changing of river course

are the serious concerns in ward no 2, 5, 6 & 7 of Tulsipur VDC. Local people reported that about

25 to 30 % of total households of these wards are Dalit followed by 26 % Muslim. These vulnerable

groups are adversely impacted by Gagan flooding.

Figure 4:Edge cutting and meandering of Gagan River in Siraha

During monsoon, the river water along sediment inundates agriculture land of ward 3 of Tulsipur

and ward 1, 2 &3 of Pipra Pra Pi VDC. With the reduced velocity, sediment slowly deposits into

the agriculture land. The river meandered in upstream of Hanuman/Mahadev temple of Tulsipur,

Bananiya ward 2, Balutole ward 5 and just east side of VDC building at ward 5. The hotspots were

verified and measured along Gagan river stretch from downstream of Banainya tole in Tulsipur.

The verified river embankment is about 4200 m in both sides, whereas in study period, it has

proposed an embankment of 4000 m along both bank of Gagan River. Most of hotspots where the

meandering took place need to be protected by earthen embankment with bio-engineering measure

in first phase as shown in map. The actual field measurement and verification depicted that there

is an additional 200 m embankment both side of Goiryawa (260 41' 40" N & 860 20' 59"E). The

starting point of embankment is Goiryanwa in Tulsipur, 800 m upstream of Hanuman temple,

Tulsipur.

Table 11: Field verified length and location for earthen embankment in Gagan river

S

N

Distric

t

Name of

River

Field Verification (FV) status

Location/Chainage Length (m) Left/Right Remarks

01 Siraha Gagan A1/ 0+000 – 0+200 200 Both side A1 is additional length

considered in FV. Goiryawa

(0+000)

260 41' 40" N & 860 20' 59"E

(1)/ 0+200 – 4+200 4000 Both side

The location of earthen embankment proposed is shown in map below and A1 refers to additional

length proposed after field verification survey in Gagan river. The list of embankment length

proposed in study and field verified is presented in Appendix 4.


18 | P a g e

Figure 5: Location of Earthen Embankment in Gagan River

Prioritization of hotspot for embankment & bio-engineering work: The most hotspot was identified along

the river during field verification and the length was measured (2,700 m) for estimation and implementation.

However total length in study period for embankment and Bio-engineering in Gagan was 4,200 rm. The

remaining embankment length of about (4,200-2,700)1500 m will be plan in 2nd phase. The location of

prioritized embankment is shown in fig. 5 of Gagan River. The summary of prioritized length is also

presented in the Table 12.

Table 12: Prioritized hotspot for construction of earthen embankment & Bio-engineering in Gagan River

District/

VDC

Name

of

River

Most hotspot of Gagan river

Location /Chainage

Length

(m)

left/R

ight Prioritized Remark

Siraha/T

ulsipur Gagan

0+000 -0+350; Banainya/Gauriyarwa

and Tulsipur boarder

350 R/B P1

Tulsipur-2, East of Mushari tole 500 R/B P1

Mahadav Manth temple, Tulsipur-1&2 600 R/B P2

Bananiya tole ward 2 opposite of

KushaLaxminiya

400 R/B P3


19 | P a g e

Tulsipur-5, East south of Balutole; D/S

of Bariyarpati Kulo

550 R/B P1

Tulsipur-6, East of Tulsipur VDC

building

300 R/B P2

Total 2,700

4.1.2 Khando River

Major loss was observed in Dighawa VDC as seen from the annual loss of agricultural land in the

area due to bank cutting, flooding, inundation and sedimentation in agriculture land. As the

difference between river bed and bank level is merely a feet, inundation and sediment deposition

is quite common during monsoon. Farmers reported that agriculture production has been

drastically reduced because of sedimentation over the agricultural land.

Figure 6: Sediment deposition and Bank cutting in Khando River

River bank Cutting and Inundation have been a big threat to ward numbers 4, 5& 6 of Dighawa

VDC. Every year a chunk of land is turned to river channel while ward number 1-4 and 7-9 of

Dighawa VDC and wards1 - 4 of Pakari VDC have a problem with inundation. Local community

reported us that water comes up to 2-3 feet and even more during monsoon.

To connect Dighawa and Pakari VDC, Department of Road is undertaking construction of RCC

Bridge in “Hulaki Road” and has also a plan to construct guide bank in both upstream and

downstream of the newly constructing bridge. The hotspots are to be protected by constructing

earthen embankment which is further to be strengthened by bio-engineering measures in first

phase as shown in figure 7 below. The Bhim Badha of left side also needs to be rehabilitated

for about approximately 150 m length at different locations. The length of embankment

proposed in study phase and field verification is presented in Appendix 4

Table 13: Field verified length and location for earthen embankment in Khando River

S

N

District Name of

River



1

Saptari Khando

A1/ 0+000 – 1+000 1000 Both side Chainage considered at DS of

Dighwa VDC 9(SadhaTole).

A1 and A2 is additional 2 (1) / 1+000 – 2+500 1500 Both side


20 | P a g e

embankment length after FV

of site.

3 A2/ 3+500 – 4+200 700 Right side D/S of RCC Bridge under

construction in Hulaki Road

The earthen embankment verified for sediment control in Khando River in Saptrai is about

2,500 m in both side and 700 m in right side, whereas in study phase, the proposed length of

earthen embankment is about 1,500 m in both side and 500 m in right side. A1 & A2 refer as

additional length after field verification survey. The verified location and additional length

proposed in field verification survey is presented in figure 7 below.

Prioritization of hotspot for embankment & bio-engineering work: The most potential hotspot was

identified along the Khando River during field verification. The length was measured (3,700 m) for

estimation and implementation. The summary of prioritized length is presented in table 14.

Table 14: Table 14: Prioritized hotspot for construction of earthen embankment & Bio-engineering in Khando

River

District/

VDC

Name of

River

Prioritized length verified in field

Location /Chainage Length

(m)

left/R

ight

Prioritized Remarks

Saptari/

Dighwa Khando

Starting Diguwa VDC-9, Mushari Tole

Via d/s Diguwa -8 /Ch. 0+00 - 0+1500

1500 R/B P1

Diguwa-3, D/S bridge under construction

along Hulki road and U/S of sediment post

installed/ Ch. 3+500 - 4+200

700 R/B P1

U/S of Hulaki road (U/S of Proposed

bridge River training work) /Ch. 1+500 -

2+500

1000 R/B P2

Left bank of Khando River, Kadmaha,

Dighwa VDC

500 L/B P3

Total 3,700


21 | P a g e

Figure 7: Location of proposed Earthen Embankment in Khando River, Saptari

4.1.3 Hadiya and Kong River

Similar issues exist in both Hadia and Kong watersheds because these two possess similar

catchment characteristics within Triyuga watershed. Erosion, land slip, and landslide during

monsoon in the upstream of Hadiya and Kong watershed causes sediment transport in the lower

reach of the watersheds. This is further enhanced by the intensified deforestation along with open

grazing in Churia region. The ultimate effect is the sediment deposition along the river stretch and

adjoining agricultural land in the downstream during monsoon, river bed level rising and reduced

productivity. Significant supports are being received from DWIDP, GIZ, DSCO, CF, DDC, and

VDC in embankment and spur construction. Additionally, numbers of bio-engineering species

(locally available1) are used to protect along the constructed river bank.

Figure 8: Proposed embankment and existing river training work in Kong River

11 Bamboo, Simal, fruit trees (banana, Mango), Karme (Besharam in local language), Khayar


22 | P a g e

The hotspots were measured and verified in field. It was also observed that people campaign and

awareness programs are to be implemented to conserve Churia, re-afforestation and need to stop

open grazing in forest area to control sediment. There are certain sections (see red circle in figure

9 & 10) of the river from where water enters to the agricultural land then to vicinity of settlement

and these locations were identified and mitigation measures were proposed. In Kong River, a small

stretch of about 200 m long embankment in the left bank of the river was constructed by District

Soil Conservation Office (DSCO) Udayapur. Moreover, the embankment verified in field in

Khong is about 1,050 m in Left bank and about 1,050 m in Right bank respectively and shown in

table 15 whereas in study period, the proposed length was 1,250 m in left bank and 800 m in right

bank. The additional length and location has been marked by A1 in river shown in figure 9.

Similarly, in Hadiya River, the field verified length of earthen embankment is1,200 m in right

side and 1,500 m in left side (table 15) whereas the proposed length of embankment in study phase

is about 1,600 m and 400 m in right and left bank respectively. The additional embankment lengths

verified in field are represented by A1 & A2 in Left bank of Hadiya River (figure 10). The proposed

embankment length in study period and field verification length and location is presented in

Appendix 4

Table 15: Field verified length for earthen embankment and location in Kong and Hadiya river

S

N

District Name of

River



1 Udayap

ur

Kong (1)/ 0+450 – 0+950 500 Left bank Chainage considered from

confluence of Trijuga& Kong

river at upstream

2 (4)/ 0+800 – 0+950 150 Right bank

3 A1/1+680 – 1+880 200 Right bank A1 is additional embankment

4 (3)/2+750 – 2+950 200 Left bank DSCO completed

5 (2)/2+100 – 2+650 550 Left bank

6 (5)/ 2+300 – 3+000 700 Right bank

1 Hadiya A1/0+400 – 0+600 200 Left bank A1additional emba. length

2 (1)/1+250 – 2+050 800 Right bank

A2/1+920-2+420 500 Left bank A2 additional emban.Length

(3)/4+000 – 4+800 800 Left bank

(2)/ 4+900 – 5+300 400 Right side


23 | P a g e

Figure 9: Location of Earthen Embankment in Kong River

Prioritization of hotspot for embankment& bio-engineering work: The most hotspot (p1) is identified along

the Kong (1,450 m) and P2 is identified (650 m). Similarly in Hadiya River length of embankments are

1,400 m. in 1st priority and 1300 m. in second priority during field verification. The length was measured

in field for cost estimation. The priority (P1) only has considered in cost estimate for 1st phase of

implementation. The summary of prioritized length is presented in table 16.

Table 16: Prioritized hotspot for construction of earthen embankment & Bio-engineering in Kong & Hadiya

River

Districts/

VDC

Mark

in

map

Prioritized embankment length and location

Location /Chainage Length

(m)

Left/Right Prioritized Remarks

Udayapu

r/Jogida

ha/Kong

1 0+450 - 0+950 500 L/B P2 Chainage

consider from

confluence of

Trijuga and

Kong river at

upstream

4 0+800 - 0+950 150 R/B P2

A1 1+680 - 1+880; Dhangadhi tole area 200 R/B P1

2 2+100 - 2+650; Dhangadhi tole area 550 L/B P1

5 2+300 - 3+000; Upper belt of Khudai 700 R/B P1

Total length priority (P1) only 1450 m in P1and 650

in P2

(A1 +2+5 nos) are priority

P1

Udayapur

/Hadiya/

A1 0+400 - 0+600 200 L/B P1 A1 additional

length

A2 1+920 - 2+420 500 L/B P2 A2 additional

length

1 1+250 - 2+050 800 R/B P2

3 4+000 - 4+800 800 L/B P1

2 4+900 - 5+300 400 R/B P1

Total length priority (P1) 1400rm in (A1+2+3) and 1400 rm and 1300 rm in Priority 2


24 | P a g e

Figure 10: Location of Proposed Embankment in Hadiya River

4.1.4Ratu River

At chainage 1+900 to 0+800 m: At a confluence of Ratu and Sunjhari Khola and downstream, Ratu pushes

flow (during monsoon) to the left bank. The ultimate effect is left bank cutting of the River. To control the

bank cutting in left bank, the spur has been proposed in design. The location was visited and verified in site

with DPO and confirmed the design data. The picture of proposed site is presented in this report for

reference.


25 | P a g e

Figure 11: Proposed location of Spur and embankment in Ratu River

At chainage3+000 m to 3+540 m: Bank Cutting and Inundation in upstream of Sunjhari Khola:

The chainage was considered from upstream of Ratu Bridge in East-West highway. The locations

severely affected by bank cutting and hotspots were visited in verification period and local

community informed that every year the area is losing land mass due to bank cutting. The spurs

have to be essential to control the bank cutting around 3+000 to 3+540 in left bank (Tulsi VDC

side). As the bank cutting height is about 2.5 m to 4 m gravel mixed soil and suggested to spur in

left bank of Ratu River. To protect bank cutting in these chainages, five spurs have been

additionally proposed with 25 m length with 100 m spacing in left bank normal to river.

Figure 12: Ratu River Left bank cutting about 3+000 area

Similarly in Chainage 5+400 to 4+900 the river is approaching/ shifting towards Patu village

resulting in to bank cutting in Patu Village. There is a small tributary at the left side of river

(opposite to Patu village) contributing noticeable amount of sediments during monsoon. As the

flow of Ratu pushed water and debris of this tributary to the left bank, a deposition occurs leading

to shift of waterway towards right bank and ultimately cutting the right bank (at Patu village area).

The spur has been proposed in right bank in design and the location has been verified jointly with

DPC, DPO and local users in site. The field verified location and length of spur is presented in

table 17 in below. The proposed gabion spurs in study period and Field Verification are presented

in Appendix 5.


26 | P a g e

Table 17: Field verified length and location of Gabion Spur in Ratu River

S

N

District Name

of

River

Location/

Chainage

No

of

spur

Length

of

spur(m)

Spur

spacin

g (m)

Orientation Remarks

1 Mahotar

i

Ratu

River

(3)/ 1+900

– 0+800

9 40 120 Spur with embankment, Normal

to flow, at Ratu (L/B)

Chainage

considerfr

om U/S of

Ratu

bridge at

E-W

highway

A1/3+000

– 3+580

5 25 100 A1 proposed additional supr as

per Field Verification of

site.Normal to River. At Tulsi

VDC (Leftbank)

(2)/ 4+900

– 5+400

5 25 100 Upper Part of Laalgadh where

SunjhariKhola meet Ratu (R/B)

Figure 13: Locations of Proposed Spur and Embankment in Ratu River in Mahotari

At chainage 12+100 m to 11+600 m): Bank Cutting and Inundation in Kalapani of Gauribas

VDC: In the first 500 m (11+600 m to 12+100 chainage), the river bends towards right side and

just is about to enter the flood water in farm land. The debris deposits in left bank. The discussion

with local revealed that every year the area is losing land mass due to bank cutting. In the later

section (chainge 12+100 m to 11+600 m), there is an inundation in agricultural land during

monsoon. The elevation difference of river bed and the bank of the river is only 0.40 m to1.5 m.

The field was visited with DPC, DPO and local people and field visit and discussion between local

people and FCO staffs recommended to provide embankment of about 500 lengths in Right bank.


27 | P a g e

Figure 14: Ratu river approaching towards farm land and bank cutting

Jaganha River starts to drain in Ankushi and encroaches, turns to agricultural land and human

settlement area. To protect right bank of Ankushi and Jaganha River in Sarpallo VDC, earthen

embankment of about 1000 m is proposed in right bank after Field Verification, whereas in design

has proposed embankment along both bank. The chainage is considered at u/s of Bajharang

Chowk, Sarpallo VDC.

Figure 15: Proposed embankment site in Ankusi & Jangahariver U/S of Bajharang chowk

Table 18: Field Verified length, location for earthen embankment in Ratu and Ankushi River in Sarpallo VDC

Distric

t

Name of

River



Mahot

ari

Ratu

River

(1) 11+600 –

12+100

500 Right bank Ratu U/S Bahunamara. Chainage

carried from the Ratu bridge U/S of

E-W Highway

Ankushi 0+000 – 1+000 1000 Right bank RATU D/S Sarpallo, Chainage are

considered at U/S of

BajharangChowk, Sarpallo VDC

ward 5


28 | P a g e

Figure 16: Locations of Earthen Embankment in Ankush and Jangaha in Sarpolla, Mahatari

Prioritization of hotspot for Embankment & bio-engineering work: The most hotspot was identified along

the Ratu and Ankushi River during field verification. The length was measured in field for cost estimation.

In Ratu River, the gabion spur and bio-engineering were designed. But in first phase of implementation/or

in priority basis, only bio-engineering works are considered in Ratu River as protection work. The cost

estimate has been prepared only for earthen embankment (1000m) with bio engineering in Ankushi.

Jangaha in Sarpallo VDC (table19). In Ratu river upstream only bio-engineering work are suggested for 1st

phase of implementation.

Table 19: Field Verified length, location for earthen embankment in Ratu and Ankushi River in Sarpallo VDC

Districts/

VDC

Name of

River

Prioritized embankment length and location

Location /Chainage Length, m Left/Right Prioritized Remark

Mahotari/

Sarpallo

/Ankushi,

Jangaha

0+000 - 1+000 Sarpallo-5 starting

from Sarpallo suspension Bridge

prgressing towards North of

Bajharang Chowk, Sarpallo VDC

ward 5

1000 Right side P1

Total length of most priority 1000


29 | P a g e

5. Cost Estimate of Prioritized Embankment & Bio-engineering

Based on the field verification, the most hotspots were identified and length were measured for

earthen embankment in Gagan River, Khando River, Kong River, Hadiya river, Ratu River and

Ankushi River in Siraha, Spatari, Udayapur and Mahottari districts respectively. The most hotspots

with prioritized length with quantity of earthen embankment and bioengineering works have been

estimated. In Ratu River, gabion spur wasdesigned but in 1stphase of implementation plan only the

bioengineering work in Ratu at Ch. 0+800–1+900; 4+900 – 5+400 and 12+ 10 –12+550 was

measured in cost estimate. Standard practice rules have been used to calculate the earthwork

quantities and vegetative measures plantation and care taking etc. District Rate of Saptari, Siraha,

Dhanusa and Udayapur for FY 2070/071 was used for analysis of Unit Rates for different civil

works items in study report and same rate has been used in verification report and cost estimate

purpose in this report. The Quantity Estimate for embankment and bioengineering in study period,

field verification and cost of prioritized section is given in Table 20. The cost Estimate of

Embankment, Spur and bio-engineering is given in Appendix 6 & 7.

5.1 Unit Rate

The Unit Rate is used same as study report rate based on the construction works Rate Analysis

Norms. Similarly, for bioengineering work, same unit rate of study period has also been used. The

basic rate taken is as per District Rate. The analysis has been done taking into account 15% of

contractor overhead (o/h) and 13% of Value Added Tax (VAT)

5.2 Cost of Prioritized hot spot section for first phase implementation

The cost estimate of the most potential hotspots has calculated. In Gagan River, 2800 m (P1, P2

&P3), in Khando 3,700 m (P1, P2& P3), in Kong (1450 m) (P1 only), in Hadiya (1400 m) (P1only)

and in Sarpallo (1000 m, P1 only) and bio-engineering works in Ratu has measured and cost

estimate was prepared. The cost for earthen embankment and bio engineering work for 1st phase

implementation on the base of priority is estimated Nrs 11.74 million in Gagan, NRs. 10.92 million

in Khando, NRs 4.71 million in Kong, NRs 4.43 million in Hadiya and Nrs 26.32 million in

(Jangaha, Ankushi) Sarpallo & Ratu respectively.

Table 20: Summary of embankment cost including Bio-engineering study period cost, Field Verified cost

Distircts River Chainage Proposed in Design Field Verified (FV) Prioritized (P1, P2...)

section Remarks

Length (m) Cost (NRs) Length (m) Cost (NRs) Length (m) Cost (NRs)

Siraha Gagan 0+000 -

4+200

8000 31,464,582 8400 33,015,327 2800 11,741,251 All

prioritized

section (P1,

P2 & P3) is

considered in

cost estimate

Saptari Khando 0+000 -

2+500,

3+500 -

4+200

3500 10,757,762 5700 17,519,870 3700 10,920,840


30 | P a g e

Udayapu

r

Kong 1350 m At

chainage

(0+800-

0+900,

2+750-

2+950,

2+099-

2+650,

0+000-

0+950)

1350 4,384,339 2150 m At

chainage (0+450-

0+950, 0+800-

0+900, 1+680-

1+880, 2+100-

2+650)

6,982,477 1450m At

chainage (

1+680-

1+880,

2+100-

2+650)

4,709,087 In Kong

River cost of

Prioritized

(P2) is not

considered

Hadiya 2000m At

chainage

1+250-

2+050,

4+000-

4+800,

4+900-

5+300

2000 6,327,723 2700m At

chainage 0+400-

0+600, 1+920-

2+420, 1+250-

2+050, 4+000-

4+800, 4+900-

5+300

8,528,116 1400m At

chainage

0+400-

0+600,

4+000-

4+800,

4+900-

5+300

4,429,420 In Hadiya

River, cost of

Prioritized

(P2) is not

considered

Mahotari Sarpallo

& Ratu

2000m At

chainage

0+000-

1+000 in

Sarpallo

and 500 at

11+600 to

12+100 at

Ratu

2500& 18

nos of Spur

in Ratu with

bio-

engineering

80,983,000 1000m At

chainage 0+000-

1+000 in Sarpallo

and 500 at 11+600

to 12+100 at Ratu

35,140,212 1000m At

chainage

0+000-

1+000 in

Sarpallo

26,319,672 Including

Bioengineeri

ng in Ratu

river at ch

0+800-

1+900,

4+900-

5+400,12+10

0-12+550.

SPUR is not

considered

Total cost of Prioritized section

133,917,406 101,186,001 58,120,271


31 | P a g e

6. Non-structural Measures

6.1 Bioengineering

Bioengineering is a vegetative measure which holds the soil and is supportive component for flood

protection work. The Bioengineering alone cannot be the absolute solution for Churia originated

river system as these rivers are characterized by flash floods, high current and inundation in the

downstream areas. In general bioengineering is combination of civil structures (Gabion wall, dry

wall, embankment etc.) and non-structures, which may increase the durability of the whole flood

protection infrastructures. So, it is high potential to the use of vegetative measures (bioengineering)

at the both sides of the river run for river bank protection against erosion due floods in low grade

river in Terai. The vegetative measures have also been recommended along sides of embankments

and spurs. The availability of local plant and list of vegetation, species, herbs, grass, bamboo,

shrub and tree which are locally available and can survive in local climate and also can as

bioengineering measures were verified with discussion in community. Some of the species that are

popular and locally available in study area in Siraha and Spatari are Dangre Khar, Kans, Dhanu

Bas, Mal Bas, Narkat, local, Khayar, Simal, Fruits (banana, mango, litchi, pineapple), Karmi

(Besharam), Jatropha, Masala plant, Babul, Kans etc. Likely, in Udayapur, the locally available

species are Karme Jhar, Kush, Napier, Kimbu, Aak and Simli. In Mahotari, the locally available

and popular species are Narkat, Sisam, Kaus, Dhanu bas, Tharu bas with fruit (Banana, mango,

Litchi)

The field verified list of plants, species with their botanical name and use for bioengineering that

fits in local situation and their use in project districts is listed in table 21.

Table 21: Field verified list of Plants, species with their use for bioengineering

Nepali

name Botanical name Character Altitude Sites Best

propagation

technique

Mostly survive in

Districts

Grasses

Babiyo Eulaliopsis

binata

Medium-sized

clumping

Terai-1500m Hot and

dry

Slip

cuttings/seeds

Udayapur

Dangre

khar

Cymbopogon

pendulus

Large

clumping

Terai-1200 m Varied Seeds Siraha, Saptari

Dubo Cynodon

dactylon

Small

creeping

Terai-1800 m Varied Stem cuttings Siraha, Saptari,

Udayapur

Kagati

ghans

Cymbopogon

citratus

Medium-large

clumping

Terai-1500 m Varied Slip

cuttings/seeds

Saptari, Udayapur

Kans Saccharum

spontaneum

Large

clumping and

spreading

Terai-2000m Hot and

dry to

moist

Slip cuttings Siraha, Mahotari,

Spatari

Katara

khar

Themeda

species

Large

clumping

Terai-2000m Varied Slip

cuttings/seeds

Siraha, Saptari

Khus Vetiveria

lawsoni

Medium-large

clumping

Terai-1500m Varied Slip cuttings Udayapur

Kikiyu,

thulo dubo

Pennisetum

clandestinum

Small

creeping

(exotic)

Terai-1800 m Varied Stem/slip

cuttings

Siraha, Saptari


32 | P a g e

Napier Pennisetum

purpureum

Large semi

clumping

(exotic)

Terai-1750 m Varied;

needs

fertile

soil

Stem cuttings Udayapur

Narkat Arundo clonax Large

clumping and

spreading

Terai-1500m Hot and

dry;

varied

Stem/slip

cuttings

Saptari, Sirha,

Mahotari

Large bamboos

Dhanu bans Bambusa

balcooa

Thick culm,

heavy

branching

Terai-1600

m

Varied Culm

cuttings

Siraha, Saptari,

Mahotari

Mal bans Bambusa

nutans

Strong,

straight culms

Terai-1500

m

Dry/varied Tradition

al method

Siraha, Saptari

Tharu bans Bambusa

nutans

Strong,

straight culms

Terai-1500

m

Varied Tradition

al method

Siraha, Saptari

Shrubs and small trees

Aak Calatropha

giganteum

Small shrub,

large fleshy

leaves

Terai-1000 m Hot and dry;

harsh

Seeds /

polypots

Udayapur

Bayer Zizyphus

mauritiana

Thorny shrub

up to 4 m high


harsh

Seeds/polypot

s

Udayapur

Assuro Adhatoda vasica Shrub up to 3

m high

Terai-1000m Varied Hardwood

cuttings

Udayapur

Kera Musa

Paradisiaca

Tee upto 5

mhigh

Tera-1300 Varied and

dry

Root suckers Siraha, Saptari

Kettuke Agave

americana

Large cactus;

sub-species

with and

without thorns

Terai-2400m Hot and dry Root suckers Udayapur

Kimbu Morus alba Small tree Terai-2000 m Varied and

dry

Hardwood

cuttings/ seeds

Udayapur

Rahar Cajanus Shrub up to 4m Terai- 1500m Varied &

Dry

Seeds Siraha

Rato chulsi Osbeckia

stellata

Shrub Terai-1500 m Varied Saptari

Sajiwan/

kadam

Jatropha curcas Shrub up to 4 m

high

Terai-1000 m Varied Hardwood

cuttings

Saptari

Simali Vitex negundo Shrub up to 6 m

high

Terai-1750m Hot and dry;

varied

Hardwood

cuttings

Saptari,

Udayapur

Thakal Phoenix humilis Small stature

palm tree


needs shade

Direct seeding

on site

Udayapur

Tilka Wendlandia

puberula

Tree up to 10 m

high

Terai-1500m Hot and dry;

harsh

Seeds/polypot

s

Saptari

Large trees

Australian

khayer

Acacia

auriculiformis

Small non-

thorny tree

(exotic)

Terai-1000

m

Hot and

dry; harsh

Seeds/polypots Siraha, Saptari

Amp/aap Mangifera

indica

Medium-sized

fruit tree

Terai-1200

m

Hot and

dry but

not stony


Badahar Artocarpus

lakoocha

Medium to large

deciduous tree

Terai-1300

m

Varied

and moist


Bakaino Melia azedarach Medium to large

deciduous tree

Terai-

1800m

Hot and

dry; harsh



33 | P a g e

Banghi Anogeissus

latifolia

Large deciduous

tree

Terai-1700

m

Hot and

dry

Seeds/polypots Saptari

Jamun Syzygium cumini Medium-sized

evergreen tree

Terai-1600

m

Moist Seeds/polypots Siraha, Saptari

Khayer Acacia catechu Large, thorny

tree

Terai-

1000m

Hot and

dry; harsh

Seeds/polypots Udayapur,

Sirhaha

Lahare

papal

Populus ×

euramerica

Large deciduous

varieties

(exotics)

Terai-1700

m

Moist Hardwood cuttings Saptari

Mashala Eucalyptus

camaldulensis

Large tree with a

thin crown

Terai-1800

m

Hot and

dry; harsh

Seeds/polypots Saptari

Nim Azadirachta

indica

Large evergreen

tree

Terai-900

m

Hot and

dry


Sal Shorea robusta Large forest tree Terai-1000

m

Varied;

dry to

moist

Seeds/polypots Udayapur

Seto siris Albizia procera Medium-sized

deciduous tree

Terai-

1350m

Moist Seeds/polypots Saptari

Sisau Dalbergia

sissoo

Large broad-

leaved tree

Terai-

1400m

Varied Seeds/polypots /

stump cuttings

Saptari

Karme

Jhar

Corydalis

chaerophylla

- Terai-1000

m

Varied;

dry to

moist

Papaveraceae Udayapur

Simli Vitex negundol - Terai-1000

m

Varied;

dry to

moist

Rutaceae Udayapur


34 | P a g e

7. Photographs:

Minutes of meeting in Sarpallo&Nahini

Pakari VDC orientation, Ranking of ETW and Khando River site

Sharing meeting with local people and Hadiya ETW location in Udayapur


35 | P a g e

Drain to be improve and ETW site fixed in NahiniMahotari

Sediment deposition in Ratu River. Proposed Spur and embankment in Ratu River, Mahottari

Existing Spur in Ratu River about 7+000 km VDRMC meeting in Sarpallo VDC


36 | P a g e

Women participation during field verification of ETW in Pakari

Existing road side drain in Nahini VDC, Mahottari and VDRMC meeting

River bank cutting in Khando river in Saptari and bank cutting in Gagan River in Siraha


37 | P a g e

Appendix


38 | P a g e

Appendix 1: Elevated Tube well, Waste Water Drain around ETW in study

report and Field Verification


39 | P a g e

Appendix 2: Rehabilitation of Flood Proofing Drainage system (FPDS) along

Access Road in study report and Field Verification


40 | P a g e

Appendix 3: Evacuation centers (EC) proposed in study report and Field

Verification


41 | P a g e

Appendix 4: Structural Measure: Embankments Proposed in study report

and Field Verification


42 | P a g e

Appendix 5: Structural Measure: Spur Proposed in study report and Field

Verification


43 | P a g e

Appendix 6: Cost Estimate of River embankment, Spur and Bioengineering in

study report and Field Verification


44 | P a g e

Appendix 7: Cost of Bio-engineering

Documents

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