DWIDP Bulletin January 2014 Series XIV DWIDP Bulletin29 January 2014 Series XIV

People's Embankment Program, Karnali River, Patabhar-9, Bardiya

Government of Nepal Ministry of Irrigation Department of Water Induced Disaster Prevention (DWIDP) DWIDP Bulletin January 2014 Series XIV 30

PEP Field Offi ce No. 4, Chitwan / Narayani River River Bank Protec on Work using Sand Bags & Training Works in, Chitwan & Nawalparasi Bamboo Pilling

Construc on of Embankment, Public Awareness Seminar, Udaypur Stud and Bio- Engineering work

River Bank Protec on Work, Sarlahi People's Embankment Program, Mahakali River DWIDP Bulletin January 2014 Series XIV

Advisory Board Kamal Prasad Regmi

Director General N Gauri Shanker Bassi I Deputy Director General Disaster Mitigation Division T Narendra Bahadur Lama Deputy Director General 2013/2014 Fiscal Year

Planning, Program and Foreign Coordination Division E ______L Chief Editor Pradeep Kumar Manandhar L Senior Divisional Engineer

Editor U Khila Nath Dahal Senior Divisional Hydrogeologist B Sundar Prasad Sharma

Senior Soil Conservation Officer Executive Editor Komal B. Dhakal P Engineer Manju Sharma D Sociologist I

Published by W DWIDP BULLETIN DWIDP DWIDP BULLETIN D DWIDP Government of Nepal Ministry of Irrigation Department of Water Induced Disaster Prevention (DWIDP) DWIDP Bulletin January 2014 Series XIV 2

Table of Contents Editorial

• Events/Activities: To address the water induced disaster in the country Disaster Preven on Technical Centre (DPTC) was established in October 1991 with the technical and fi nical support from Japan Interna onal Coopera on Agency (JICA). This • Check Dam – A Hydrological Technique to technical centre was an inter-disciplinary ins tute consis ng experts from Control Concentrated Flow Erosion diff erent government organiza on and focusing on all aspects of disaster preparedness. To ins tu onalize this organiza on the technical centre was converted • Monsoon 2013 Associated with Severe Cyclonic into the department - Department of Water Induced Disaster Preven on Storm “Phailin” in Nepal (DWIDP) under the then Ministry of Water Resources on February 2000 to work as focal agency for water induced disaster management in Nepal. Overall goal of DWIDP is to contribute to achieving the na onal goal of • An Introduction of Bamboo Porcupine Spur poverty allevia on through minimizing human casual es and damages of infrastructures due to water induced disasters by the appropriate management and conserva on of rivers and river basins of Nepal. Its • June 17, 2013 Flood and the Master Plan of tasks involve i) technology development work, ii) Training, study and informa on work, and iii) Structural disaster mi ga on work. In the process Mahakali Rehabilitation Works, Darchula of strengthening the DWIDP on January 2002 River Training Division from the Department of Irriga on (DoI) was merged with this department. Then the organiza on was structured with two major divisions and six sec ons • Glossary of Disaster Terms at the centre and seven division offi ces and fi ve sub-divisions covering the 75 administra ve districts of the country. Moreover, seven fi eld offi ces operated under the People's Embankment Program (PEP) to look a er river • Standards, Norms and Criteria: Hazard control ac vi es related to 14 specifi c rivers in the tarai. The structure of the departmental head quarters shows its origins, with one division covering Categorization and Defi nition the former DPTC ac vi es (e.g. technology development, training) and the other covering the former DoI's river engineering division tasks. To cope with the changes in the development ac vi es, address the demands of the na on on water induced disaster mi ga on works, adapta on of innova ve and appropriate technologies the exis ng organiza on structure of DWIDP has been restructured. The new organiza on has been structured with three major divisions and 18 sec ons at the centre but there has been no change in the number of divisions, sub-divisions and fi eld offi ces DWIDP Bulletin at the district/project level. The organiza on structure in the centre may overcome the short comings of the previous one and will boost the ac vi es Janurary 2013 Series XIV of the department for be er ins tu onal development and effi cient and eff ec ve delivery of its services. The three divisions and the sec ons within the divisions are categorized so as to enhance the ac vi es of the division. Under the Planning, Program and Foreign Co-ordina on Division there are Planning and Program Sec on, Monitoring and Evalua on Sec on, Foreign Co-ordina on Sec on, Study and Research Sec on and Peoples' Embankment Program Sec on. These sec ons will co-ordinate the diff erent line ministries, sec ons/offi ces of the department, stakeholders and the aff ected benefi ciaries in planning and programming the short and long term plans, prepare project reports for loan/grant assistance from the donor agencies and eff ec ve execu on of the Peoples' Embankment Program. In the River Training Division there are River Training Sec on, Mechanical and Electrical Management Sec on and Emergency and Early Warning Management Sec on. The sec ons within this division will supervise the ongoing river training ac vi es and monitor its progress, mobilize and manage the emergency response opera on on water induced disasters along with early warning measures. Similarly, under the Disaster Mi ga on Division there are Landslide Management Sec on, Watershed Management Sec on, Training and Informa on Sec on, Technology Development Sec on, Bas -tar Management Sec on, Disaster Management and Environment Cover Photo: Percupine works at Holiya, Banke Sec on. These sec ons will give con nuity to the former DPTC ac vi es along with manage landslide mi ga on measures, watershed management and implement measures to protect towns and agricultural lands (bas -tar) in the foothills along the rivers banks. The Deputy Director Generals will be in charge of the divisions and the Government of Nepal sec ons will be under the senior divisional engineer/engineering geologist/ Ministry of Irrigation hydro-geologist. At the district/project level all the divisions and sub- Department of Water Induced Disaster Preventionntion divisions will be headed by the Senior Divisional Engineers instead of (DWIDP) Engineers in the sub-divisional offi ces as per the previous organiza on www.dwidp.gov.np structure. By this amendment the technical man-power of the divisions can increased to cope with the present issue on insuffi cient technical manpower to supervise the construc on ac vi es. Finally in overall, it is expected that the amendment of the organiza on Photographs of Cover Picture structure will enhance the ac vi es of the department and its divisional People's Embankment Program, Karnali, River offi ces in eff ec ve delivery of its services. Patabhar-9, Bardiya DWIDP Bulletin January 2014 Series XIV 3

Events/Activities:

Retirement New Appointment

Director General Pradip Raj Pandey Mr. Kamal Prasad Regmi, Joint Secretary of has retired due to age factor on Poush Ministry of Irrigation has been appointed as the 30, 2070. The department honors his 11th Director General of DWIDP from Magh contributions to the department and wish 14, 2070. He was also the Director General of him for his bright future and prosperous life. DWIDP from 2068-2-23 to 2069-1-15.

Public Awareness Seminars Having with following expected outcomes DWIDP conducted Seminar for public awarness in Udayapur District from 12-13 Kartik 2070 (Oct 29-30, 2013). Expected outcomes Rapport build-up among service providers and receivers of water induced disaster management, Make familiar with the available services in the district on disaster mitigation activities, Enhanced technical, behavioral and social knowledge on water induced disaster risk reduction Establishment of mutual goal and coordination among the line agencies and communities. In the Seminar there were had 64 participants from the member of District Natural Disaster Relief Committee, Red Cross Society, school teacher, social worker, civil society, women social mobilizer, VDC secretaries, local NGO/CBO and local media. The general objective of the program is to mitigate the disaster through non structural mitigation measure. The specifi c objectives of the seminar were: To bring together all the related organizations working in disaster fi elds to manage and mitigate water induced disasters. To increase awareness level among local people, district level line agencies towards causes and risks of water induced disaster. To bring common solution in raised-issues To work in coordinated and collaborative way to reduce water induced disaster To provide technical knowledge on water induced disaster to the stakeholders, community leaders, social workers and teachers. To make familiar with the existing status and opportunities in the fi eld of disaster management, mitigation and reduction that provided by the different agencies in the district. to review the needs and demands of the community on water induced disaster mitigation. to rank the problems on the priority basis. 21st Advanced Course Training DWIDP has been conducting an Advance Course Training (ACT) and a General Course Training (GCT) for knowledge and skill development of engineers and sub-engineers of the department and line agencies annually. These trainings will enhance the capacity of the engineering professionals and technicians to execute the required task on disaster reduction and mitigation. These types of training are conducted for thirty plus working days and awarded certifi cate to the participants which will be useful to fulfi ll the promotion criteria for the Civil Service. So far, 20 events of Advance Course Training and 23 events of General Course Training have already been conducted. Following the past years, the 21st ACT is now ongoing which will be fi nished on 03rd of Magh 2070. The general objective of the training is to enhance knowledge and skill of the technical personnel working in the fi eld of water induced disaster The specifi c objectives of the program are as follows: to provide technical and theoretical knowledge about material testing, geology, hydrology, landslide, SABO works, river training works, watershed management, GIS, remote sensing and bio-engineering works with reference to water induced disaster to familiarize disaster management in Nepal, process and procedures of procurement of works and services, environmental impact assessment and report writing techniques regarding to water induced disaster management and mitigation to make fi eld study of the different project site(s) of DWIDP, for case study to produce report on WID mitigation measures. DWIDP Bulletin January 2014 Series XIV 4

Restructuring To fulfi ll the increasing role and responsibility in effective and effi cient way the organization of the department has been restructured. ces ce No. 1, Bidur, Nuwakot 1, Bidur, ce No. Kaski 2, Pokhara, ce No. Dang 3, Lamahi, ce No. Surkhet 4, Birendranagar, ce No. Doti 5, Dipayal, ce No. ce No. 1, Biratnagar, Morang 1, Biratnagar, ce No. Dhanusha 2, Janakpur, ce No. Bara 3, Parwanipur, ce No. Bhaktapur 4, Jagati, ce No. Rupandehi 5, Bhairahawa, ce No. Banke 6, Nepalgunj, ce No. Kailali 7, Dhangadhi, ce No. Projects Divisions Offi & Sub-division Central Level Central Division Off Division Division Off Division Off Division Off Division Off Division Off Division Off Division Off Sub-Division Off Sub-Division Off Sub-Division Off Sub-Division Off Sub-Division Project Project Section Section Financial Financial Act, Legal Act, Implementing Implementing Group Section Group Administration Administration Administration Administration Advisory SectionAdvisory Section Section Basti-tar (Agri Irrigation) Irrigation) (Agri Watershed Watershed Section Deputy Director Genral Director Deputy Management Section Management Management Section Management Environment Environment Management Section Management Director General Director Disaster Mitigation Division Mitigation Disaster Training & Information & Information Training Landslide Management Landslide Management Disaster Section Technology Development Development Technology Ministry Irrigation of Department of Water Induced Disaster Prevenion Disaster Induced Water of Department (Civil / Irrigation) / Irrigation) (Civil Mechanical Mechanical & Electrical Emergency & Early Warning Warning Early River Training Division Training River Deputy Director Genral Director Deputy River Training Section Training River Management Section Management Management Section Management (Civil / Irrigation) / Irrigation) (Civil Section Coordination Division Coordination Deputy Director Genral Director Deputy Program Section Program Monitoring & Monitoring Foreign Co- Foreign Evaluation Section Evaluation Planning, Program & Foreign & Foreign Program Planning, People's Embankment Embankment People's ordination Section ordination Study & Research & Research Study Planning & Program Section & Program Planning Organization Chart of Department of Water Induced Disaster Prevenion Induced Disaster ChartOrganization Department of Water of DWIDP Bulletin January 2014 Series XIV 5

Abstract of Human Resource (Staffi ng) in Department and Division, Sub-division Offi ces Department Division Offi ces Sub-Division S.N. Post Class Service Group Subgroup Department Total (PIG)* (7 Nos) Offi ces (5 Nos)

1 Director General Gaz. I Engineering 1 1

2 Deputy Director General Gaz. I Engineering Civil Irriga on 2 2

3 Deputy Director General Gaz. I Engineering Agri-irriga on 1 1

4 Senior Divisional Hydro-geologist Gaz. II Engineering Geology Hydro-geology 2 2

5 Senior Divisional Engineer (agri) Gaz. II Engineering Agri-irriga on 1 1 2

Senior Divisional Engineering 6 Gaz. II Engineering Geology Engineering geology 1 1 Geologist

7 Senior Divisional Engineer (civil) Gaz. II Engineering Civil Irriga on 10 10 7 5 32

8 Senior Divisional Engineer (mech) Gaz. II Engineering Mechanical Cons. Mch. Mntnc.** 1 1

9 Under Secretary (account) Gaz. II Adminstra on Account 1 1

10 Account Offi cer Gaz. III Adminstra on Account 1 7 2 10 11 Sec on Offi cer Gaz. III Adminstra on General admin. 1 1 12 Legal Offi cer Gaz. III Judicial Legal 1 1 13 Engineer (civil) Gaz. III Engineering Civil Irriga on 10 40 88 31 169 14 Engineer (agri) Gaz. III Engineering Agri-irriga on 2 2 4 15 Engineering Geologist Gaz. III Engineering Geology Engineering Geology 1 1 16 Engineer (hydrology) Gaz. III Engineering Civil Hydrology 1 1 2 17 Engineer (hydropower) Gaz. III Engineering Civil Hydropower 1 1 18 Engineer (mechnical) Gaz. III Engineering Mechanical Cons. Mch. Mntnc.** 1 1 2 19 Engineer (highway) Gaz. III Engineering Civil Highway 1 1 20 Sociologist Gaz. III Miscellaneous Miscellaneous 1 1 21 Sub-engineer Gaz. III Engineering Civil Irriga on 6 1 2 12 21 22 Sub-engineer Gaz. III Engineering Civil Highway 1 1 23 Accountant Non-Gaz.I Adminstra on Account 1 6 2 9 24 Nayab Subba Non-Gaz.I Adminstra on General admin. 3 4 2 9 25 Senior Mechanic Non-Gaz.I Engineering Mechanical Cons. Mch. Mntnc.** 1 2 3 26 Computer Operator Non-Gaz.I Miscellanous Miscellanous 2 2 27 Typist Na. Su. Non-Gaz.I Adminstra on General admin. 1 1 28 Lab boy/Assistant Non-Gaz.I Miscellaneous Miscellanous 1 1 29 Senior Associa on Organizer` Non-Gaz.I Engineering Agriculture 2 2 30 Kharidar Non-Gaz.II Adminstra on General admin. 1 5 3 9 31 Assistant Accountant Non-Gaz.II Adminstra on Account 22 32 A.O. Non-Gaz.II Engineering Agriculture 1 1 33 Driver Class less Engineering Mechanical 11 34 Offi ce Helper Class less Adminstra on General admin. 5 30 9 44 Grand Total 62 56 155 69 342 * PIG = Project Implemen ng Group ** Cons.Mch.Mntnc. = Construc on Machinery Maintenance DWIDP Bulletin January 2014 Series XIV 6

Check Dam –A Hydrological Technique to Control Concentrated Flow Erosion

Lal Chand Pradhan Senior Consulting Engineer/ Former DDG, DWIDP

1. INTRODUCTION

In a sloping topography, concentrated fl ow of water erodes the soil mantle deepening its course forming gullies. A check dam is a hydrological low dam structure constructed across a gully or a channel or any other water course like a torrent to prevent and protect the water course from deepening by decreasing the velocity of water fl ow and the erosive power of runoff. It promotes the deposition of eroded materials, minimizes or stops channel and lateral erosion, and hence it stabilizes a gully or a watercourse. Fig.1: Check dams in Fewa watershed 2. FUNCTIONS

Check dams are designed and constructed to meet the following functions: i) reduce the velocity of water, ii) raise the bed level and reduce the slopes in a gully by silting up and trapping the silt from going downstream, and support the unstable side slopes and prevent channel and lateral erosion, iii) reduce the water depth by widening the gully or channel bed, and promote water percolation in the soil, and conserve water for plant growth for stabilizing banks. Fig.2: Check dams in Lankuridanda, Dolakha (Photo: L.C.Pradhan) DWIDP Bulletin January 2014 Series XIV 7

3. TYPES OF CHECKDAM General Characteristics Advantages Disadvantages

Brushwood Made of wooden poles and Simple, Takes long time for the check dams Check dam brush, Use local materials, to develop the roots and get (Fig.3) Least permanent of Low cost, established all the other types, After the roots and shoots come out, Suitable for small gullies of 1 they can form a to 2 meters in depth, long term barrier. Low cost, where materials are locally available.

Loose stone Made of loose stones or rocks, Use local materials If not made properly and sizeable Check dam Stability and strength depend Simple stones (Fig.4) on the size of rocks and quality Low cost are not used, the stones will be of the construction, and (where stones moved Commonly used in the gully are abundantly by the large water fl ow, control works, where stones available) and they may be quickly damaged. are abundantly available

Boulder Made of big boulders or rocks. Use locally Transportation of the big boulders Check dam stability and strength depend available materials, is diffi cult (Fig. 5) on the size of the boulders such as boulders, (especially, if not located upslope of or rocks and quality of the Simple the site) construction. Low cost (where Large voids, if not properly fi lled up Commonly used in the gully boulders are in control works, where boulders abundantly the dam, may create water jets, or rocks are abundantly available) which could be destructive available. If properly made, if directed towards banks are almost like a permanent structure and durable

Gabion Made with wire crates Flexible and Costlier than loose stone or Check dam (Gabion Boxes) of different permeable boulder structures (Fig. 6) sizes fi lled with stones, Suitable, where Gabion has to be brought Flexible, land mass is from outside or imported, Preferred where big boulders unstable not locally available; are not available Economical so the community has to bear compared to other the cost of the gabion solid structures Need skilled labor for their construction

Masonry Made of cement masonry or Permanent and Costly Check dam concrete solid structure Materials (cement, rods) (Fig. 7) Not commonly used in Have aesthetic look are not locally available ordinary locations, except Need more engineering design, to protect important and skilled labor for the construction. infrastructures such as road, building etc DWIDP Bulletin January 2014 Series XIV 8

4. DESIGN CONSIDERATIONS Where, a = the total vertical distance between the fi rst and the last 4.1 Site Selection check dam in that portion of the gully or torrent, b = Se * d’ / 100 = the total vertical distance calculated according to Following considerations need to be taken for the selection the compensation gradient for that portion of the gully, d’ = of sites for the construction of check dams: i) the site should the horizontal distance between the fi rst and the last check be wide enough to limit specifi c runoff. To accommodate dam in that portion of the gully or torrent, H = average higher run off, it is necessary to select a wide enough place height of the check dams. to limit the specifi c run off and the scour depth. The spillway 4.4 Hydrological Design has to be large enough with adequate free board to take expected peak run off, otherwise the side foundation of the check dam will be washed out and the check dam will Run off Estimation be by- passed by the runoff and destroyed. ii) A check There are various methods or formulas to estimate the dam should be made at a straight and fi rm stream bed runoff rate. However, the rational formula is a simple and bank. It should not be made on a curve and junction method and uses the watershed area, the rainfall intensity, of gullies or streams, and just below the gully junction. iii) and a factor called a dimensionless coeffi cient. Stable site should be located for the base foundation and side foundation. It is necessary to build the fi rst check dam The peak rate of runoff is calculated by using the following on good foundation base rock as it affects the foundation Rational Formula: of the rest of the check dam above. iv) The selection of the site is also restricted by the height of the structure. If the Q = C * I * A / 360 elevation difference between two successive sites is too tc high, one or more sites have to be selected in between so Where, that the structure height will fulfi ll the conditions. Q = The rate of runoff in cubic meter per second or

cumecs, C = Dimensionless run off coeffi cient; Itc = The For gullies which are part of other natural drainage system, rainfall intensity, that is the rate of rainfall in mm per hour only check dams with a long life-span are suitable (Agpaoa, for the designed frequency for a duration equal to the time A., et al, 1976). of concentration, tc ; A = Watershed area in hectares. 4.5 Hydraulic Design 4.2 Spacing of Check Dams 4.5.1 Notch Design The spacing of the check dams should be so placed that the line joining the top of the lower check dam and the The notch of the check dam, i.e. the spillway section, bottom of the successive upper check dam gives the is designed by considering that the spillway has to gradient. This gradient for the kind of soil in the gully bed accommodate the peak runoff, otherwise the side or stream bed will give a non-erosive velocity of fl ow. This foundation of the check dam will be washed out and the gradient is known as the compensation gradient. For check dam will be destroyed. general practice, the compensation gradient is taken as 3 to 5 per cent slope.

Horizontal distance between successive check dams is given by the relation:

d = h * 100/ (So- Se),

Where, d = spacing between two successive check dams, h = height of the check dam up to the notch, So= existing slope of bed in %, Se= stabilizing slope of bed in% (in general it is 3 – 5 %).

4.3 Number of Check dams

It is calculated from the following formula: Figure 8: Front view of a check dam Notch/weir or spillway can be designed by using the Number of check dams = (a – b)/ H, following formula: DWIDP Bulletin January 2014 Series XIV 9

Rectangular Notch: Francis’s Formula -

1.5 Q = 1.84 * Bsp * Hsp Where,

Q = Peak runoff in cumecs, Bsp = Length of the Notch in meters, Hsp = Height of Notch in meters. Specifi c runoff, q = Q/ Bsp cumecs /meter

For a trapezoidal notch, length of the notch is calculated as the average of top and bottom lengths of the notch.

4.5.2 Foundation Depth Figure 10: Scour depth in a check dam (B.Hiller, 1979) The foundations are given to a check dam to anchor it in Q = runoff; H = height of energy line; q = specifi c runoff; the ground for its stability so that it does not give away or hcr = critical height; h = fall height of check dam; hw = over turn when the run off or peak fl ows occur and the dam water cushion height; hs = scour water depth (Ds); hsh = is silted up. The following considerations need to be taken scourable depth; ls = scour hole length; bsh = breadth while designing and constructing the foundation of a check of scour hole; hf = height of foundation; ( Units in m, sec) dam: i) the depth of foundation must be taken below the scour level, ii) in the erodible strata if Ds is the anticipated The scouring action of the current is not uniform and it maximum depth of scour below the designed highest fl ood is all along the bed width; and scouring is deeper at the level including that on account of possible concentration of obstructions and also at bends than normal. Therefore, the fl ow, the minimum depth of foundation below the highest maximum scour depth has to be determined. fl ood level should be taken as 1.33 * Ds, iii) the scour depth is not to be taken from the present bed level but Scour Depth Estimation from one to be expected in the future after siltation of the lower check dam and after the establishment of new bed i) Normal scour depth is calculated using Schocklitch’s gradient due to the reduced bed load after the erosion Formula: control, iv) take a 1.0 m foundation as a rule of thumb. 0.2 0.57 0.35 Scour Depth, DS = (4.75 * h * q ) /dm

Where, DS = Scour depth in meter below water level; h = water level difference in meter above and below the check dam, q = run off in cubic

meters /meter width in the spillway; dm = Grain diameter in mm which divides bed material in a way that 90 % is smaller than dm.

ii) Breadth of scour hole is calculated as: Breadth of Scour Hole or Apron = 1.5 * Length of the Notch

iii) Length of scour hole is calculated as: Length of Scour Hole or the Apron = 4 * (0.467 * q2/3) 1.5 * h 0.5 Figure 9: Foundation depth of a check dam (B. Hiller, 1979). Side Foundations: Giving side foundations of a check Scour Depth dam into the gully side slopes prevents the destructive fl ows of water around the dam and consequent scouring Scour occurs when the bed velocity of the stream exceeds of the banks. Keying a check dam into the side slopes and the velocity, which can move the particles of the bed bottom of the gully greatly enhances the stability of the material. Velocity varies with the gradient, the hydraulic structure, which is important where expected peak fl ow is depth and the characteristics of the bed and the banks. large, and soils are highly erosive. When the velocity is retarded, silt is dropped; and when the velocity is increased, silt is picked up. Scour is worse when Apron: Apron must be installed on the gully bottom and the fl ow is falling. It depends more on the water depth than protective works on the gully side slopes below the check on the gradient. A stream or river has to adjust its velocity to dam, otherwise fl ows may undercut the structure from what its bed and banks can stand by changing its section. downstream and destroy it. The apron should be roughly level on its surface and go down about 0.3 m below the original bottom elevation (Burchard H. Heede, 1976). DWIDP Bulletin January 2014 Series XIV 10

4.6 Structural Design 6. MAINTENANCE AND REPAIR

Structural design involves the determination of the General Maintenance dimensions of the various components of the check dam, its strength and stability. The safety of the check dams is After the construction, maintenance of different types of mostly endangered by scouring. Foundation depth and check dams is very important to be followed for the stability, spillway size and shape have, therefore, to be selected longevity and effectiveness of the structures. Structures taking scouring depth into consideration. which are not maintained well may have disastrous consequences by possible destructions. Maintenance of Check dams are designed for: i) Safety against overturning; structural measures must be continued for at least two or ii) Safety against sliding; and iii) Safety against the bearing more years after the treatment year. pressure on the foundation soil. Middle third rule should hold since common check dams are gravity check dams. Normally maintenance consists of the following aspects: Stability test for the check dam is carried out same as retaining wall. i) Inspections: Treated areas must be inspected at least once a year or more. A check up 5. CONSTRUCTION CONSIDERATIONS must be done before and after the monsoon. Basically all the check dam structures, General Construction Considerations watercourse (bed and bank erosion, obstacles etc.) and slope protection must be checked. The following general construction considerations should be taken into account to get a satisfactory result from ii) Care of plantations and of watercourses: check dam construction (Hiller, 1979). - Drainage: Weeds should be removed and Construct check dams at the same time as the cleaned in ditches, and repair ditches. treatment of the upper watershed and adjacent side slopes (like plantation, diversion channel, retaining - Slopes: Wherever necessary grass cutting walls, trimming steep slopes). or restoration of grass or plant cover should be done; it is to be checked for if there are any Select the appropriate construction site, and design newly formed rills, gullies and slides developed properly as per site condition. with brushwood check dams and with other Choose the best construction materials available vegetative methods of slope stabilization. nearby. - Water courses: Water courses should be For loose stone or boulder check dams, make good cleaned of deposits, woods, branches, big dry masonry structures with big, well shaped, hard stones etc. Erosion trends must be recognized stones. Use the biggest and hardest stones for the and controlled immediately. Changes of water spillway section and the foundations. courses must be monitored and controlled. For gabion check dams stone size must be bigger than the mesh. Only dry masonry may be used with well Repair works: Check dam structure such as brushwood, shaped and hard stones. The gabions must be well loose stone, boulder, gabion or masonry check dam must and fi rmly tied fi rst to close the gabion box itself and be repaired timely once it gets damaged or worn out. second to fi x the gabion with its surroundings. - Check dams have to be checked for the Gabions should not be exposed to fl owing or falling conditions of the spillway section, bed and water especially if there is a bed load. bank foundations or damages to any structural The foundation must be fi rmly based in the sub-soil part due to rotting, hitting or abrasion. Scouring and in the banks. The foundation depth depends on damage above and below the structure and the quality of the soil and the rock. condition of the apron must be looked at. The spillway section must take the peak runoff fl ow. - With these structures, every damaged part Prevent water fl ow by-passing the check dam sides by has to be repaired, changed or patched up. providing guide walls or wing walls. Scouring damage must be repaired by setting a better protection (big stones, gabions, Plan the life span of the structures for longer period to masonry etc.). justify economically. - Rotting check dams (brushwood) are Maintenance is as important as the construction itself. exchanged by removing the old one or DWIDP Bulletin January 2014 Series XIV 11

constructing a new one in front of the old one. 13/2, FAO of the UN, Rome, - Out washing of brushwood check dams must 4. Gupta, S. K., K.G. Tejwani and H.N. Mathur (1975). be restored and dead plants replaced. Soil and Water Conservation Research 1956 -71, Indian Council of Agricultural Research ,New Delhi Supplementary works: Normally at the fi rst attempt full 5. Hattinger, Hubert, ( 1976), Torrent Control in the success may not be gained in gully stabilization, especially Mountains With Reference to the Topics, FAO in new constructions. Some additional structures may be Conservation Guide – 2: Hydrological Techniques for necessary for bank protection or other works; and in such Upstream Conservation, FAO, Rome. cases, supplementary structures should be constructed. 6. Hiller, Bernhard, (1979). Manual Calculation of Check 7. CAUSES OF FAILURE Dams, Department of Soil and Water Conservation/ The main causes of failures of check dams may be Swiss Assistance for Technical Assistance, attributed to human as well as natural factors. Kathmandu, Nepal. 7. Heede, Burchard H., (1976). Gully Development and Human factors for failure of check dam may include Control: The Status of Our Knowledge, US Department inadequate design and construction considerations, which of Agriculture, Forest Service, Colorado, USA may be specifi ed as given below: 8. Heede, Burchard H , (1977). Gully Control Structures a. Faulty or inadequate design steps, and Systems, FAO Conservation Guide – 1Guidelines specifi cations or process followed: for Watershed Management, FAO of the UN, Rome. incorrect spacing, incorrect effective 9. Michael, A.M. and T. P. Ojha (1966). Principles of heights, inadequate spill way section, less Agricultural Engineering, Jain Brothers, Jodhpur. or no foundation depth, no provision or inadequate keying of foundation or sides 10. Pradhan, Lal Chand, (1985). Design, Construction of check dams, no provision of wing walls, and Evaluation of Small Scale Structures for no or inadequate apron; Controlling Concentrated Flow Erosion. M.S. Thesis, The University of Arizona, Tucson, Arizona,U.S.A. b. Construction process not followed 11. Shah, Bashir Hussain , (1992). An Economic Approach properly or faulty construction or low grade to the Design of Erosion Control Structures Using of construction materials used because of Local Materials, Regional Watershed Project, UNDP: low knowledge, skill, experience, economy FAO of the UN, Kathmandu. or mere negligence; 12. Soil Conservation and Watershed Management c. No or inadequate maintenance activities; Measures and Low cost Techniques, Soil Conservation no or very limited monitoring; and Watershed Management Component d. Deteriorating watershed conditions (NARMSAP),( 2004). DSCWM, Kathmandu. because of human interventions. 13. Soil Conservation and Watershed Component (NARMSAP) (2005). Training Hands out on Bio Natural factors for failure of check dam may include Engineering and Survey, Design and Estimation unexpected fl ow conditions and debris fl ow or mass of Soil Conservation Activities, Department of movement because of cloudburst or high rainfall intensities Soil Conservation and Watershed Management, more than that were considered in the design, natural Kathmandu, Nepal. disaster or phenomenon like earthquake, geological 14. Sthapit, Keshar Man, (1998). Teaching Material on conditions, and tectonic movement beyond human control. Soil Conservation Engineering, Institute of Forestry/ International Tropical Timber Organization, Project REFERENCES PD: The Training and Manpower Development in 1. Agpaoa, A., et al (1976). Manual of Reforestation and Community Forestry Management, Pokhara, Nepal. Erosion Control for the Philippines (Compiled by H. J. 15. Schwab, Glen O., Richard K. Frevert, Talcott W. Weidelt), gtz, Eshborn. Edmisnster and Kenneth K. Barnes(1981), Soil and 2. Department of Water Induced Disaster Prevention, Conservation Engineering, John Wiley and Sons, / Department of Civil Engineering, Insti tute of New York. Engineering, TU , (2001) Water Induced Disaster 16. United States Department of Agriculture Fores Prevention Training Manual, Department of Water Service, (1969). Watershed Structural Measures Induced Disaster Prevention, Lalitpur Handbook, Washington 3. Geyik, M. P , (1986),FAO Watershed Management 17. U.S. Department of Agriculture (1973). How to control Field Manual Gully control FAO Conservation Guide Gully , Washington. DWIDP Bulletin January 2014 Series XIV 12

Monsoon 2013 Associated With Severe Cyclonic Storm “Phailin” In Nepal

Visiting faculty, Department of Enviormental Science and Engineering,

Kathmandu University, Nepal Mani Ratna Shakya (Senior Meteorologist) E-mail- [email protected]

1. Introduction The deep depression over north Andaman Sea intensifi ed into a cyclonic storm Phailin on October 9. It then moved slightly westwards, intensifi ed into a severe cyclonic Monsoon is the main source of rain for livelihood of storm in the forenoon and further intensifi ed into a very human beings in a mountainous country like Nepal. severe cyclonic storm at 06:00 UTC on 10 October 2013 The monsoon onsets in Nepal in the eastern part on extending into the coordinate of 15.00N and longitude 10 June, and withdraws completely from Nepal on 23 90.50E, about 800km southeast of Paradip, 850km east- September. However, the monsoon prolongs for several southeast of Kalingapatnam, and 870 km east-southeast days, sometimes, when it is affected by cyclone. It solicits of Visakhapatnam (Fig.1) unexpected natural disasters such as heavy rain with strong winds, fl oods etc. altering the activities of human lives reluctantly. In this context, the monsoon 2013 is an example in the history of Nepal that is extended by 22 days against the normal. The monsoon 2013 was withdrawn completely from Nepal on 19 October against the normal date 23 September. This has prolonged the monsoon 2013 in Nepal for 127 days. The normal monsoon day in Nepal is 105 days. This is the longest period of monsoon extended in Nepal after 25 years since 1989.The main reason behind the extension of the monsoon is the occurrence of severe cyclone named “Phailin” in the north of Andaman sea of Bay of Bengal in the middle of October.

Emerge of the event: The system was fi rst noted as a tropical depression on Fig 1. Severe cyclonic Storm Phailin October 4, 2013 in west of Pnom Penh in Cambodia within The cyclone Phailin as intensifi ed rapidly as a very severe the Gulf of Thailand. Over a few days, it moved westwards cyclonic storm on October 10, is equivalent to a category within an area of low to moderate vertical wind shear. It 1 hurricane on the Saffi r-Simpson hurricane wind scale moved out of the Western Pacifi c Basin on October 6 and (SSHWS). On October 11, the system became equivalent emerged into the Andaman Sea. to a category 5 hurricane on the SSHWS before it started DWIDP Bulletin January 2014 Series XIV 13 to weaken during the next day as it approached the Indian e) Based on post-cyclone survey report, maximum of state of Odisha. The storm track can be observed in Fig. 2. storm surge of 2-2.5 meters above the astronomical tide has been estimated in the low lying areas of The very severe cyclonic storm, Phailin crossed Ganjam district of Odisha in association with the Odisha & adjoining north Andhra Pradesh coast cyclone and the in-land inundation of saline water near Gopalpur in Odisha around 1600 UTC of extended up to about one kilometer from the coast. 12th October 2013. It subsequently weakened over land as a result of frictional forces, before it was last noted on October 14, as it degenerated Synoptic features associated with the cyclone: into a well marked area of low pressure ( www. imd.gov.in). The synoptic features associated with the cyclone explain clearly the alteration in weather with space and time. Hence, it is of great importance to know the feature of the cyclone in detail which is explained as below. • A trough extending from eastern parts of Jammu & Kashmir to east-central Arabian Sea across Haryana, east Rajasthan and Gujarat region in mid-tropospheric level observed on October 4th. • The trough extends from Nepal to east-central Arabian Sea across Uttar Pradesh, West Madhya Pradesh, Maharashtra and Konkan & Goa on 5th and became less marked on 6th. • Another upper air cyclonic circulation laid Fig 2. Storm track of severe cyclonic storm Phailin 2013. over Assam & Meghalaya and neighbourhood source:(www.imd.gov.in). extending upto 3.1 kms above mean sea level The salient features of the storm: on 6th. It persisted over the same area on 7th and laid over Tripura & neighbourhood extending a) Very cyclonic Storm Phailin is the most intense upto 3.1 kms above mean sea level on 8th. It laid cyclone after Odisha Super Cyclone of 29th over Bangladesh & adjoining north Bay of Bengal October 1999, that crossed India coast affecting extending upto mid-tropospheric Levels on 9th. different parts of South Asia. • An off shore trough at mean sea level extending b) There was rapid intensifi cation of the system from south Maharashtra coast to Kerala coast on from 10th to 11th October morning leading to an 6th and became less marked on 7th. increase in wind speed from 45 knots to 115 knots. • An east-west trough extending from Assam & c) At the time of landfall on 12th October, maximum Meghalaya to Gujarat region across Jharkhand sustained surface wind speed in association with and Madhya Pradesh between 3.1 & 5.8 kms the cyclone was about 115 knots (215 kmph) and above mean sea level on 7th. It extending from estimated central pressure was 940 hPa with Manipur to Gujarat region across Jharkhand pressure drop of 66 hPa at the centre compared and Madhya Pradesh on 8th, from north Andhra to surroundings. coast to south Gujarat region across Maharashtra extending upto 3.1 kms above mean sea level on d) It caused very heavy to extremely heavy rainfall 9th. over Odisha leading to fl oods, and strong gale wind leading to large scale structural damage and • The cyclonic storm, Phailin over east central Bay storm surge leading to coastal inundation over of Bengal moved slightly westwards, intensifi ed Odisha. into a severe cyclonic storm and laid centred DWIDP Bulletin January 2014 Series XIV 14

at 0830 Hours IST , the 10th October 2013 near Lat. 14.5°N and Long. 91.0°E about 820 km southeast of Paradip, 870 km east-southeast of Kalingapatnam and 900 Km east-southeast of Vishakhapatnam. It intensifi ed into a very severe cyclonic storm and lay centred at 1430 Hours IST of today near Lat. 14.5°N and Long. 91.0°E about 820 km southeast of Paradip, 870 km east- southeast of Kalingapatnam and 900 Km east- southeast of Vishakhapatnam. • An upper air cyclonic circulation lies over south Chhattisgarh and adjoining Telangana & Vidarbha extending upto 3.1 km above mean sea level. Fig 3. Cyclone Phailin advancing North West towards Nepal and adjoining areas on 12 October 2013 at 21:30 UTC. • Another upper air cyclonic circulation lies over Saurashtra & neighbourhood extending upto mid- Table 1. Rainfall in Nepal. tropospheric levels. • An east-west trough extends from Saurashtra & Rainfall Rain (mm) Rain (mm) Rain(mm) (mm) on on 14 on 15 on Stations Kutch to centre of cyclonic storm across interior 13 ctober October October 16 October Maharashtra, south Chhattisgarh and north 2013 20 13 2013 2013 Andhra Pradesh upto mid- tropospheric levels. Biratnagar 2.9 35.1 0 00 Rain and fl oods associated with cyclone Dhankuta 00 54.6 61.9 00 Phailin in Nepal: Taplejung 00 40.0 52.5 6.2 Kathmandu 00 43.9 21.5 0.2 The affect of cyclone was observed with thunderstorm Pokhara 00 23.5 44.5 30.7 activity in association with strong wind and heavy rainfall in Dang 00 3.0 12.8 NA the eastern region of Nepal in early morning on 13 October, Jumla 00 Traces 00 Traces the second day ( Maha Nawami ) of Dasai. However, the weather was fair and sunny in entire Nepal on 12 October, Nepaljung 00 Traces 1.4 00 the fi rst day ( Maha Astami) of Dasai. Birendranagar 00 Traces 2.6 00

The storm advanced into north west affecting the central and Source Department of Hydrology and Meteorology western parts of Nepal on 13 October towards afternoon. Rainfall occurred for whole day on 14 and 15 October. The Conclusion: impact of the cyclone continued until 16 October afternoon The occurrence of cyclone in Indian Ocean and adjoining affecting various parts of Nepal, however, far western Bay of Bengal and Arabian sea is a common phenomenon during monsoon season in South Asia. However, late region of Nepal left totally unaffected by the cyclone during appearance of severe cyclonic storm such as Phailin the entire period of impacts of Cyclone in Nepal. Hence, towards the end of monsoon might be disastrous, as it almost all parts of the western region remained dry and may extend the monsoon period for several days which enjoyed a fair weather during Dasai festival ( Fig 3). may solicit unexpected natural disasters in the country. It damages the agricultural products such as paddy and The rainfall recorded at various places of Nepal are shown other outputs as well. Hence, the prolonged monsoon in Table 1.The rainfall amounts are small in fi gure but, may be hazardous for human beings and it is essential to the saturated land surface during the monsoon season be noted with precautions. explored fl oods in Kosi and Gandaki rivers in Nepal. DWIDP Bulletin January 2014 Series XIV 15

An Introduction of Bamboo Porcupine Spur

Sah D.N., Ph.D. SDE, DWIDP

1. Introduction year during the monsoon Nepal has to bear with major fl ood problem caused mainly by heavy rainfall and compounded Approximately 6000 rivers and rivulets with a total by degraded environment. Flooded rivers carry heavy load drainage area of about 194,471 km2 fl ow through Nepal; of sediments causing erosion, damaging crops, destroying 76% of this drainate area is contained within Nepal. Based private and communal properties and infrastructures on available hydrological data, estimated annual runoff and threatening the survival of many villages. Therefore from river of Nepal is 220 billion cubic meter with average fl ood control measures rand very high in the priority list annual precipitation of 1530 mm, out of which 5.8 billion of many communities and especially of the poorer section cubic meters is estimated as recharge and remaining 214.2 of the population which suffer the most from the fl oods billion cubic meter as surface runoff. (Water Resources than better off families. Unfortunately conventional fl ood Strategy, Nepal, 2002). control measures such as embankment and spurs provide only a partial protection and they are technically very There are three types of rivers in Nepal, classifi ed based demanding and costly. Putting up such structures often on the nature of their source and discharge. The fi rst exceed the resources especially the fi nancial capacity category is perennial rivers that originate in the Himalayas of the government. But fl ood control must be pursued in and carry snow-fed fl ows with signifi cant discharge, even many fronts. in the dry season. These include the kosi, Gandaki, Karnali and Mahakali. The second category’s rivers originate in the Tremendous volume of water that fl ows in hundreds of big Midlands or Mahabharat range of mountains and are fed and small rivers also frequently creates serious threats by precipitation as well as ground water regeneration. They because of their potential for adverse effects. Minimizing are Mechi, Kankai, Kamala, Bagmati, West Rapti and these adverse effects require large amount of technical Babai rivers. Although these rivers are perennial, they are and fi nancial resources. Unfortunately, neither have rivers commonly characterized by a wide seasonal fl unctuation been properly harnessed to minimize their adverse effects in discharge. The third category rivers originate from the nor have available water resources been fully utilized for Siwalik Range. These rivers are seasonal with little fl ow benefi cial purposes. during the dry season, and characterized by fl ash fl oods during the monsoon. Topographically, Nepal is a mountainous country. Mountains and hills account for about 80% of the total Most of them originate from Mahabharat and Chure range national land. The only exception is the Terai plain, a and some from high up in the Himalayas and fl ow through low and fl at land, stretching east to west in the southern the Hills into the lowland before they enter India and join the part of the country along the Indian border. Nepal has Gangas. These immense water resources hold out on one unique topography with the altitude variation from 60- m hand a promise of wealth and huge development potential at Jhapa in the south east to 8,848- m Mt. Everest in the for the nation and on the other hand, frequently loom over north. Almost all of the rivers fl ow from northern mountains to people and environment as threat and menace. Every DWIDP Bulletin January 2014 Series XIV 16 and hills to southern Terai plain. Rivers originating from river could be embanked within the resources available. various form, high altitude topographic regions carry heavy Furthermore, aggradations of riverbed create constant sediment loads. On the one hand steep slope gradient, threat to the embankment, even if they were constructed. intense precipitation and sparse forest cover have made hills very vulnerable to erosion. On the other hand, these Because of the desperate need for the additional farmland rivers cause heavy seasonal fl ood damaging agricultural in recent decades, farmers have the tendency to encroach land and properties in the hills and Terai. Weak and fragile upon fl ood plains and reclaim riverbeds, thus narrowing geology of Nepalese hills compounded with intense rainfall the natural river widths. This has made the problem of during the monsoon season and decreasing vegetative fl ood control even more diffi cult to tackle. They wish to cover often result in a debris torrent, laden with boulders embank the rivers within the natural riverbanks. Therefore, causing threats to lives and property. the planning engineers often face serious problems of land acquisition. Most of the rivers collect very high gradient before entering into Terai, forcing them to transport heavy sediment load. Almost all of the rivers fl owing in the Terai plain require As they enter onto the Gangetic plain, the rivers spread some sort of fl ood controls measures. out and their gradients decrease abruptly. This results Although Nepal Government spends millions of rupees in a decrease in sediment transportation capacity. Such every year for this purpose, it is far too little for the need. obstruction produces deposition of bed load causing the The available fi nancial resources from the government for rivers to spread out inundating vast areas of cultivated one river may just be adequate for the protection of one land. Thus the fl ood problems in Nepal have geological, village while several others remain endangered. topographical, hydrological as well as manmade dimensions. So it is beyond the capacity of government alone unless the affected people also contribute in one way of another The main effort in the fl ood control measure in Terai to solve their own problem. They have to come out of this should be to provide safer passage of fl ood water at dependency syndrome and search for ways and means to minimum costs minimizing damage with an approach and protect themselves from recurrent fl ood. Instead of always technology suitable for prevailing Nepalese conditions. looking for costly and hi-tech means, they should also Nepal experiences major fl ood problems during the embank on appropriate and locally affordable techniques monsoon (July to October) caused by incessant heavy with proven quality and success. rainfall. The problems caused by heavy rainfall are bank erosion, inundation and fl ooding of land and properties The rate of sediment deposition in Terai estimated by and sedimentation. During the incessant monsoon rain different researchers is as much as 5 cm to 30 cm in year. a considerable areas of paddy fi elds, houses, roads and This is mainly the case on river originating from Chure channels are fl ooded. Moreover, due to high sediment range. Terai is fl at; the main river channels often are not load, riverbeds rise up forcing rivers to change course, able to contain the large volumes of discharge that occur which in turn destroys vast areas of cultivated land. during the monsoon. This commonly results in fl ooding of the surrounding agricultural area. Recurrent fl ooding and Because of the aggressive lateral erosion, farmer search sediment deposition increasing river width are becoming for a long time been desperate to devise means for fl ood serious problems of concerning in Terai. control works. If the problem is discussed with local people, their demand will immediately be to construct Catastrophic events that cannot be controlled can, to some spurs and embankment with boulder protection, that too, degree, be rendered less dangerous by advance planning in gabion crates. Embanking of river is also not an ultimate and preparation. In addition to preparations for emergency solution to the fl ood problem. River training in the sense of response, rescue and relief, a number of actions will be channeling the whole of river length seems to be a solution taken to mitigate the effects of disasters in the water sector. to the recurrent fl ood problem. However river training for Numerous studies have been conducted on low cost the entire stretch of the river is far too expensive and thus fl ood control system. However, no low cost, appropriate, out of consideration. The costs will be high that not a single DWIDP Bulletin January 2014 Series XIV 17 locally available, effi cient and emergent system has been A wide variety of materials is used in construction of spurs developed. and groynes. According to the type of construction used, two broad classes of groynes may result – (a) Solid groynes 2. Materials and Methods which do not permit appreciable fl ow through them and (b) Permeable groynes or spurs which permit restricted fl ow Bamboo Porcupine is very effective method for fl ood through them. Solid groynes may be constructed of a core fi ghting .It is highly used for cheap and best method in of sand or sand and gravel or soil as available in the river erosion control and to divert the unwanted fl ow of fl ood bed, protected on the sides and top by strong armour of water these days. Even the diverted fl ow of Koshi River stone pitching or concrete blocks. Other types are ‘balli” due to damaged embankment was controlled by fl ood crates packed with stone inside a wire screen, or rubble controlling expert technician by RCC percupine and others. masonry. The section of the groyne is to be designed in accordance with the materials used and the force of the Making 60mm to 80mm dia. Bamboo pile & hammering into fl ood. The head of a groyne needs special protection and the ground including cutting as per size, pointing the end, generally provided with a launching apron in addition to below ground with attachment of bamboo made cubical increased pitching thickness. Permeable spurs generally shape with 6 square faces is called block of percupine. consist of timber stakes or piles, driven into the river bed Its confi guration of location and alignment depends on the for some depth below the level of deepest anticipate scour, direction of fl ow and discharge of water. Bamboo fabric and joined together to form a frame work by other pieces of made by nailling bamboo pieces & fi xing them in place by timber, the space in between being fi lled with brush wood or tying with 20 SWG wire or by nailling with 75mm. Nails branches of trees. The toe of the spurs is often protected by at alternating points, fabric is kept on the side of u/s and a mattress of stone or other material. The permeable spurs, d/s of percupine to control the fl ow of sedimented water to instead of defl ecting the current, slow it down, and induce settle the sediment. Types of percupine may be difference silt deposition. They are thus especially useful in rivers as the discharge of fl ood water quantity. which carry a considerable amount of silt in suspension. Bamboo pile spurs can be constructed as impermeable They are, however, of a more or less temporary nature and spur as well as submerged spur. Permeable spur can are particularly susceptible to damage by fl owing debris be constructed from bamboo pile. Wooden piles can or ice. Again in boulder and gravel beds, pile driving is not also be used where available as cheaper alternative. It feasible and permeable spurs have to be put up by weight is constructed transverse of fl ow to reduce velocity and down timber beams at the base by stones or concrete induce sedimentation. It is found highly successful in rivers blocks; the other parts of the frame can then be tied to having high sediment load (Jha, H. et al., 2000). these beams at the base. (Singh, B., 1983) 3. Results

Technology appropriated with porcupine to site condition is affordable, sustainable and effi cient. This is provided with the observations made in the Ghurkauli River Training and Management Sub Project, Nepal.

Sixty percent of major natural disasters in the world occur in the Asia and Pacifi c region. Human activity mostly concentrated in fl ood plains along the river banks which are often convenient and attractive locations for settlement, transportation, agriculture, industries and economic activity. However, intensive urbanization in the fl ood plain areas may create fl ooding due to acceleration of runoff caused by rooftop, pavement and insuffi cient drainage. To solve this Porcupine fl ooding problem usually structural fl ood control measures DWIDP Bulletin January 2014 Series XIV 18 are constructed despite their high cost and diffi cult in land acquisition. Without proper control of urbanization, the existing fl ood control facilities become less effective. æyfxf 5}gÆ Moreover, upstream urbanization, irrigation project and — uLtf lu/L* deforestation cause more fl ooding, and damages in the downstream areas. Therefore it is important to introduce the non-structural fl ood control measures to support the zfGt, ;f}Do / :jj]udf structural fl ood control measures. (Tingsanchali, 1996). afn'jfsf] dL7f] ;'uGw lkP/ Preparation of piles involves pointing of tips of a number of ;nn–;nn au]sf] logs to be used as piles required during the construction of gLn gbLsf wf/x?nfO{ fl ood fi ghting structures (The River Bureau, A Handbook of lryf]/]/, layf]n]/, sf]k/]/ Flood Fighting Methods). xfdLn] g} qm'/ agfPsf xf}+ The reasons of failure of solid spur and embankments jiff}{+ nufP/ k|s[ltn] are classifi ed into followings four categories: improper cf]9]sf] xl/of] bf];Nnf alignment of embankment, scouring of the toe portion of Rjf/Rjf/L Roft]/ revetment and spur dykes with insuffi cient apron in term of length and depth, improper connection of spur dykes with wtL{ gª\UofpFb} embankment, and sucking out of fi lling materials of spur df6f]sf] k|f0f lyr]/ dykes and embankment through the covering works i.e. df6f] dfly g} /dfpg vf]Hg] gabions, concrete block etc. (Final Report, 1995). xfdL dfgjn] References yfxf 5}g dg'ioTjsf] s'g l;F9L kf/ u¥of}+ < 1. Final Report, 1995. Effectiveness Study of River lxhf] k|s[ltn] k|f0fsf] Training Works, Example of Success and Failure, lev dfuL cnfk ubf{ Water Induced Disaster Prevention Technical Centre (DPTC), Pulchowk, Lalitpur, Nepal. lgd{dtfsf] r/dr'nLdf gfFr]sf] xfd|f] dgn] 2. Jha, H. et al., 2000. Flood Controls Measures, Best ;s]g Tof] /f]bg ;'Gg Practices Report. First Edition, Kathmandu, Nepal. ;s]g Tof] efiff a'´\g 3. The River Bureau, Ministry of Construction of Japan, cfh pxL k|s[lt A Handbook of Flood Fighting Methods, Published by cfo{3f6af6 p7]/ All Japan Confederation of Flood Fighting (Defense), Administration (Management) Bodies. ?k abn]/ k|fs[lts k|sf]k ag]/ 4. Singh, B., 1983. Fundamentals of Irrigation xfd|f] 5ftLdf s'lNrP/ Engineering. Published by Nem Chand and Bros: xfd|f] k|f0f lgdf]7L /x]5, Roorkee 247667 lgdf]7L /x]5 lg/Gt/ 5. Tingsanchali, T.,1996. Floods and Human Interaction. yfxf 5}g p;sf] Experiences, Problems and Solutions. Professorial cfo' slt < Inaugural Lecture. Water Engineering and Management Program, School of Civil Engineering, AIT, Bangkok, xfd|f] cfo' slt < Thailand. yfxf 5}g ..

6. Water Resources Strategy, Nepal, 2002. Published by * hn pTkGg k|sf]k hgr]tgfd"ns 3'DtL uf]i7Lsf ;xefuL, Water and Energy Commission Secretariat (WECS), rf}tf/f, l;Gw'kfNrf]s Kathmandu, Nepal. DWIDP Bulletin January 2014 Series XIV 19

June 17, 2013 Flood and the Master Plan of Mahakali Rehabilitation Works, Darchula

Mahendra Pd. Badu, SDE WIDP Div. No. 7 Dhangadhi

1. Background Massive Flood in the River Basin Mahakali River also known as The Sharda, originates from the From the mid night of June 15, the fl ow in Mahakali started to Greater Himalayas at Kalapaani at an altitude of 3600 m, joins rise, the people from the low land were shifted to safe places with the Dhauli Ganga, Gori Ganga, Chameliya, Ram Ganga and which usually happened to occure in the past as well. But this the Sarju River on its route until it descends into the plains into time it did not stop with it and continued to rise with huge debris with it and hit to many areas of importance, like residential, India and known as Sharda, which meets the Ghaghra (Karnali in Nepal) in Indian Territory at about 100 km from the existing Upper Sharda Barrage at Banbasa. The river borders the Nepalese Mahakali Zone and the Indian state of Uttarakhand. The river fl ows in a gorge section in the upper region. Mahakali fl ows for a length of 223 km length in Nepal and 323.5 km in India up to its confl uence with Ghaghra river.

River Basin Characteristics Mahakali is one of the fi ve major river basins of Nepal which is shared with India and has a total basin area of 14871 km up to Upper Sharda Barrage, about 34 per cent of which lies in Nepal. The total catchment area is 17,818 km up to Lower Sharda Fig. 1 Barrage. commercial, recreational, religious and historical places and In Nepal, It lies entirely in the Far Western Region of Nepal and even in the areas of security importance. Hundreds of private in the Mahakali Zone which has four administrative districts and public buildings were collapsed and diminished in the - DarchulaBaitadi, Dadeldhura, and Kanchanpur District . massive fl ood. Major destruction as well as future threat is in the Khalanga Bazar the Head Quarter of Darchula district and its vicinity, like Dashrathnagar, Chhangru, Ghat Bazar, Tikar Important Towns and Villages in the River Basin Kheda, Main administrative area (Police, Telecom, School etc), Hospital complex, Galphai bazar, Ghatta area, Namaskar etc. Besides many villages in both the banks of the Mahakali river, Besides these area there is huge loss of land and properties in the important towns beside which it fl ows are DarchulaKhalanga, different villages of Bramhadev, Dhap, Dattu, Uku and Lali Jauljibi, Julaghat, Chandani, Dodhara, and Mahendranagar in VDCs, of Darchula District. The fl ood started to hit in the areas, Nepal. And Dharchula Bazar Balwakote, Jauljibi, Jhulaghat, in the morning and major distruction was done within 10/12 hrs, Banbasa, Tanakpur, etc., in India lie to the west of Mahakali because of which the people could not protect their stationary river. Photographs (Fig. 1 & 2) show two different developing properties, however the loss of life of only one human life has stages of the part of DarchulaKhalanga before destruction. been registered from Dhap VDC. DWIDP Bulletin January 2014 Series XIV 20

2. Master Plan of the Rehabilitation Works: After the massive fl ood in the basin a technical committee led by the division chief of DWIDP-Dhanagadhi, reached the site on 20th June 2013 and started immediate response works to protect the fl ood affected areas. High level offi cials including the Chairman of the council of ministers and the the member ministers visited the site on the following days. On the recommendation of the council of ministers a high level technical team led by Regional Director MWRID, Surkhet, also visited the site inspected the emergency works and recommended the immediate rehabilitation works to protect the district H/Q Darchula from further damage. On 1st & 2nd, Oct. 2013 Director General of DWIDP visited the site and directed the division offi ce to accelerate the study works and the Master Plan of the rehabilitation works. Rehabilitation And Protection Works The whole area is categorized in two groups for the rehabilitation and the protection work namely the core area, that covers the Fig. 2 Khalanga Bazar and its vicinity and the other area that refers to the area other than the Khalanga Bazar. The rehabilitation It is natural for a river to damage to the weaker bank, the and the protection work is again divided in two groups as the process is accelerated with the increase in discharge and the bed/ emergency works and the infrastructure development works. suspended load. The left bank of the river on Nepal side was mostly unprotected or partially protected with some temporary Emergency work structures while the right bank was protected with rigid structures After the June 17, 2013 fl ood, immediate protection works were and even reinforced with some concrete studs, especially in the started especially for about 3 months during the monsoon. Some Khalanga and its vicinity which naturally diverted the heavily toe protection works with studs were constructed in the possible loaded fl ood to the Nepal side and triggered the heavy bank cuts vulnerable sites especially in the core area of Khalanga. Since in the Khalanga area of Darchula. As a result the land occupied many buildings are still in a great risk of fl ood damage in a long by some offi ce in Nepal on the left bank, before fl ood has now stretch of the river, which cannot be protected at once in a shot, gone on right bank of the river. Similarly it was also happened on emergency work is hence expected to be continued during the project execution period. Table 1 shows the estimation of the both the sides of the river in the D/S of it. emergency works. This fl ood now has left the message that our settlements in the Table 1: Budget and Expenditure for Emergency Work river basin need to be protected suffi ciently considering the safety of the people and property on both the sides of the river. At the 2070/71 moment there are many buildings hanging over the bank on both Fiscal Year 2069/70 2070/71 to Total the sides and are waiting for immediate start of reconstruction 2075/76 14.5 19.5 works. Government of Nepal is now planning to construct the Budget allocated 5 million million million retaining structures with inspection road, as that of Indian side, Expenditure till (Dec. 13 5 million 8 million as far as possible. In this context, the issue has also been raised in 2013) million the 4th JSTC (Joint Standing Technical Committee) meet to make Future budget need @ 60 60 a joint effort to understand the fl ood behaviour of Mahakali river 15 million per year million million and carry out mitigation measures. In the 4th JSTC It is agreed TOTAL (Rs) 92.5 to form a mechanism at the local level to exchange information Source: DWIDP - Division No. 7 so as to minimize the effect of similar calamities in the future. 2.0.1 River Training Infrastructures There is no discharge measuring devices in the area in the The following infrastructures would be constructed to protect the Mahakali river or in its tributaries, the discharge at Banbasa river banks and to beautify the area left behind the recent fl ood. barrage (with the catchment area of 15544 sq km) shows the RCC Retaining Wall with studs, 4.3 km. record fl ow of 5 lacks 44 thousand 476 cusecs on June 18, 2013. Access road along the protection work.4.3 km. The catchment area of Mahakali with respect to the Bridge at 4-6 m wide RCC block launching along the protection work. Khalanga, Darchula is found to be 3421 sq km. 8.5 km Gabion Toe Wall, 3 m height and 4.5 m launching. Slope stability and bioengineering works DWIDP Bulletin January 2014 Series XIV 21

The whole protection work is divided in two phases and stages depending upon the site condition and the importance of the location. Similarly the protection measures applied also categorized from simple gabion toe wall protection to RCC retaining walls with counterforts and proper PCC block launching. District head quarter Khalanga is taken as the core area of protection where the RCC retaining walls are preferred, whereas the other area in the periphery of the core area within the Khalanga VDC and the area other than the Khaklanga VDC, like Bramhadev, Dhap, Dattu, Uku, Lalietc are also taken into account for the protection works. Table 2.2 shows the area and the length to be protected. Table 2: Area and the Length to be Protected

S. Protection Area/VDC Location Type of Protection Work Remarks No Length (m) Dashrathnagar 550 Chhangru 450 GhatBazr 250 TinkarKheda 250 Khalanga Bazar (Core R.C.C. Retaining wall with stud 1 Main administrative area 950 Area) protection Hospital Complex 250 Galphai Bazar 700 Ghatta Area 250 Namaskar 900 Other Villages of Kimtadi, Khettebagar, Gabion Toe wall protection 2 2000 Khalanga VDC Masinbaluwa Protection

Bramhadev, Dhap,Dattu,Uku 3 Other VDCs 6500 Gabion Toe wall protection and Lali

4 Emergency Work Gabion Toe wall protection

Source: DWIDP-Division No. 7 of varying heights are proposed for different stretches. Heights of 6, 8, 10, and 12 m are taken as the standard heights for the 3. Design Considerations design purpose. The design criteria for the fl ood protection structures for such Design of Counterfort: a river in a boulder stage have been determined after reviewing different literatures regarding river training.The criteria have also Minimum design height of the wall is required as 6 m, as been adopted on the basis of experiences of different disciplines mentioned above; the walls hence are reinforced with the working in similar fl ood control works. counterforts to economise the cost of construction. On one hand it is quite diffi cult to estimate the foundation depth for Design Discharge and High fl ood level the walls in such undefi ned channels on the other hand it is not Mahakali River is a border river and has no hydro-meteorological easy to go up to the required foundation level, in the river in station for the measurement of the discharge in the basin, up to such a boulder stage with a slope of 1 in 100 to 1 in 80 in some the border bridge at Khalanga (Catchment Area 3421 sq km). stretches, it is advised to either anchor the walls on the rock or The fl ood estimation is either interpolated from the known on big boulders underneath or to give some front cut-off or the discharge of Banbasa barrage (Catchment Area 15544 sq km) or shear key whatever is appropriate in the site. Foundation of the to be calculated from the empirical formula. Different possible counterfort would be laid on the fi rm strata underneath, which methods have been adopted to calculate the discharge in the basin naturally would need to be fl ushed with the lean concrete to give to assume the high fl ood level. It is quite diffi cult to estimate the the even surface. Together with this 4-6 m of Block launching height of the High fl ood level (HFL) in such undefi ned section and 6-9 m of gabion launching is provided to protect scour at the of the river, HFL estimation in this case is made from the fi eld toe of the wall. Furthermore the studs of 3m*2m are proposed at observation with some 1.5 to 2 m free board allowances to 10 m spacing to minimise the fl ood impact on the walls. overcome the huge velocity head likely to come in the fl ood time. Backfi lling of the counterforts is to be done with the width Depending on the high fl ood level estimation, the retaining walls depending on the site condition while the provision of the DWIDP Bulletin January 2014 Series XIV 22 minimum of 5.50 m roadway is made throughout the length as far as possible. Stairs are provided at appropriate locations to facilitate the people to go down the river banks for different purposes. Together with the bio-engineering means, Breast wall of random rubble masonry (1:4) is proposed at appropriate locations for the hill slope protection. Suffi cient drainage facilities is provided with the provision of longitudinal and the cross drainage at appropriate locations.

4. Project Cost & Financial Plan Cost of the Civil Work Cost of the civil works of the protection work is illustrated in the Table 3 Table 3 : Component wise cost of the Civil Works

S. No Component Amount (Million) % of total Core Area 1 Counterfort walls 893.03 43.77 2 Foundation/Toe Protection 569.38 27.91 3 Backfi lling, Roadway and Drainage Works 92.11 4.51 4 Hill slope Protection 193.18 9.47 Other Area 5 Other Villages of Khalanga VDC 50.00 2.45 6 Other VDCs 150.00 7.35 Both Area Emergency Work 92.50 4.53 Total cost of Civil works 2040.20

Source: DWIDP-Division No. 7 Project Cost Summary: Table 4: Phasewise Financial Plan for Rehabilitation and Management Work Mahakali is a border river, India has been protecting their settlement areas along the river while the Neplese people are Finance Required in Phase wise (Millions) living along the unprotected river banks. Because of the fact the S.N recent fl ood adversely affected on the Neplese side on its major Phase/Fiscal Year Total Amount Allocation settlements. Being a border river, it has shifted the practical 1st Phase border in the basin in many places after the fl ood. River naturally 1 F.Y 2070/071 575.50 attacks the unprotected bank and shifts towards it if one side 2 F.Y 2071/072 731.80 of the bank is left unprotected. Shifting of the river in such a way will lead to the shifting of the practical border between the 3 F.Y 2072/073 731.80 countries which ultimately requires not only huge money but 4 F.Y 2073/074 360.80 comes to be almost impossible to acquire the land so went on 2nd phase the other side of the river. Because of the national interest linked 4 F.Y 2073/074 310.00 with it sets the top priority for its execution. 5 F.Y 2074/075 345.10 The total fi nancial cost of Mahakali fl ood damage rehabilitation Total Amount Nrs. 3055.00 work is Nrs. 3,055,000,000 (Table 4) which includes the protection work of the core area with emergency protection Source: DWIDP-Division No. 7 work and the bank protection work along the river other than the 5. Project Implementation Plan district H/Q. The whole project work is divided in two phases, The entire project has been planned to complete in fi ve years, with 8 no of packages in Phase I and 5 in phase II with 5 years of total project period. Summary of the project cost and its yearwise from the Fiscal Year 2070/071 to the Fiscal Year 2074/75. The fi nancial requirement of the project is shown in the table 4. civil works as well as the Institutional Development works, techincal assistance, procurement of vechicles etc will be implemented simultaneously from the beginning. DWIDP Bulletin January 2014 Series XIV 23

GLOSSARY OF DISASTER TERMS accountability & partnership. (IASC Acceptable Risk Guidance Note on Using the Cluster Approach Nov 2006) Degree of human or material loss that is perceived by the Command community or authorities as acceptable The direction of members and resources of an organization All Hazards Approach in the performance of the organization’s Dealing with all types of emergencies/disasters that may roles and responsibilities. Authority to command is impact on communities and the environment using the established in legislation or by agreement and operates same set of management arrangements and includes both vertically within an organization. natural and man-made hazards. Communications Capacity Specifi cally, the means of communications, for example, “The combination of all the strengths, attributes and roads, railways, telephone lines, radio, resources available within a community, society or television, fax, internet. Broadly, dissemination of disaster organization that can be used to achieve agreed goals” management messages using a variety of means to people Chemical Hazards and organizations at various stages of the disaster cycle. Hazards involving chemicals or processes which may Comprehensive Approach realize their potential through agents such as fi re, The development of disaster arrangements to embrace explosive, toxic or corrosive effects the aspects of prevention preparedness, response and Cluster recovery. A “cluster” is essentially a “sectoral group” and there Control should be no differentiation between the two in terms of Control is the overall direction of the activities in a given their objectives and activities; the aim of fi lling gaps and operation. ensuring adequate preparedness and response should be the same. (IASC Guidance Note on Using the Cluster Coordination Approach Nov 2006) The bringing together of organizations and resources in Cluster Approach accordance with the requirements imposed by the threat or impact of the emergency. The Cluster Approach aims to strengthen humanitarian response capacity and effectiveness in fi ve key ways: Coping i) ensuring suffi cient global capacity is built up and Coping is the manner in which people and organizations maintained in key gap sectors/areas of response; ii) act, using existing resources within a range of expectations identifying predictable leadership in the gap sectors/areas of a situation to achieve various ends. Coping capabilities of response; iii) facilitating partnerships and improved are a combination of all the strengths and resources that inter-agency complementarily by 18 Unoffi cial translation are useful in reducing the effects of disasters. of Nepali version maximizing resources; iv) strengthening accountability; and v) improving strategic fi eld-level Contingency Planning coordination and prioritization in specifi c sectors/areas of response by placing responsibility for leadership A management process that analyses specifi c potential and coordination of these issues with the competent events or emerging situations that might threaten society or operational agency. (IASC Guidance Note on Using the the environment and establishes arrangements in advance Cluster Approach Nov 2006) to enable timely, effective and appropriate responses to such events and situations. Cluster Leads: Disaster A “cluster lead” is an agency/organization that formally commits to take on a leadership role A serious disruption of the functioning of a community or a society causing widespread human, material, economic within the international humanitarian community in a or environmental losses which exceed the ability of the particular sector/area of activity, to ensure affected community or society to cope using its own resources. A disaster is a function of the risk process. It adequate response and high standards of predictability, results from the combination of hazards, conditions of DWIDP Bulletin January 2014 Series XIV 24 vulnerability and insuffi cient capacity or measures to example of such plans. reduce the potential negative consequences of risk. ECC/Emergency Coordination Center Or Facilities established to control and coordinate the An event, either man-made or natural, sudden or response and support to an emergency. progressive, the impact of which is such that the affected community must respond through exceptional measures. Emergency Management Team Disaster Management A group or team of disaster management personnel headed by an incident manager, which is responsible for There could not be a single organization solely responsible the overall control of the emergency for all aspects of disaster management. ESLO/Emergency Services Liaison Offi cer The management task is to bring together, in an integrated organizational structure, the resources of many His/her task is the liaison and co-ordination of activities organizations that can take appropriate action in times of pre, post and during response. disasters. Emergency Management Disaster Plans The organization and management of resources and An agreed set of arrangements for preventing, mitigating, responsibilities for dealing with all aspects of emergencies, preparing for, responding to and recovering from a disaster. particularly preparedness, response and rehabilitation A formal record of agreed disaster management roles, called emergency management. It involves plans, responsibilities, strategies, systems and arrangements. structures and arrangements established to engage the normal endeavors of government, voluntary and private Disaster Risk Management agencies in a comprehensive and coordinated way to respond to the whole spectrum of emergency needs. This A development approach to disaster management, this is also known as disaster management. focuses on underlying conditions of the risks which lead to disaster occurrence. The objective is to increase capacities Early Recovery to effectively manage and reduce risks, thereby reducing the occurrence and magnitude of disasters. Decisions and actions taken after a disaster with a view to restoring or improving the pre-disaster living conditions of Disaster Risk Management Arrangements the stricken community, while encouraging and facilitating necessary adjustments to reduce disaster risk. Recovery Linkages between the Offi ce of the Prime Minister through (rehabilitation and reconstruction) affords an opportunity to the various levels of government disaster committees, develop and apply disaster risk reduction measures. community response teams, national disaster management offi ce and emergency operations center (EOC) Hazard Disaster Risk Reduction A potential or existing condition that may cause harm to people or damage to property or the environment. The The conceptual framework of elements considered with magnitude of the phenomenon, the probability of its the possibilities to minimize vulnerabilities and disaster occurrence and the extent and severity of its impact can risks throughout a society, to avoid (prevention) or to vary. In many cases, these effects can be anticipated and limit (mitigation and preparedness) the adverse impacts estimated. of hazards, within the broad context of sustainable development. Or Disaster Risk Reduction Plan A potentially damaging physical event, phenomenon or human activity that may cause the loss of life or injury, A document prepared by an authority, sector, organization property damage, social and economic disruption or or enterprise that sets out goals and specifi c objectives environmental degradation Hazards can include latent for reducing disaster risks together with related actions to conditions that may represent future threats and can have accomplish these objectives. different origins: natural (geological, hydro meteorological Disaster Support Plans and biological) or induced by human processes (environmental degradation and technological hazards). Refers to those plans, which are designed to address Hazards can be single, sequential or combined in their specifi c hazards and are used in support of national origin and effects. Each hazard is characterized by its disaster planning arrangements. Aircraft crashes are an location, intensity, frequency and probability. DWIDP Bulletin January 2014 Series XIV 25

Hazard Analysis The knowledge and capacities developed by governments, That part of the overall planning process which identifi es professional response and recovery organizations, and describes hazards and their effects on the community. communities and individuals to effectively anticipate, respond to, and recover from, the impacts of likely, Or imminent or current hazard events or conditions. Disaster Preparedness Activities and measures taken in advance “Identifi cation, studies and monitoring of any hazard to to ensure effective response to the impact of hazards, determine its potential, origin, characteristics and behavior” including the issuance of timely and effective early warnings Hazard Mapping and the temporary evacuation of people and property from threatened locations. The process of establishing geographically where and to what extent particular hazards are likely to pose a threat to Prevention people, property and the environment. Regulatory or physical measures to ensure that disasters Integrated or “All Agencies Approach” are prevented or their effects mitigated. Involves the inclusion of all relevant agencies and/or Or departments that can assist in the effective “Activities to provide outright avoidance of the adverse implementation of disaster management arrangements. impact of hazards and means to minimize related environmental, technological and biological disasters Lead Agency called Prevention”. Depending on social and technical The agencies identifi ed as primarily responsible for feasibility and cost/benefi t considerations, investing responding to a particular disaster in preventive measures is justifi ed in areas frequently affected by disasters. In the context of public awareness Lifelines and education, related to disaster risk reduction changing attitudes and behaviour contribute to promoting a "culture Public facilities and systems that provide basic life support of prevention". services such as water, energy, sanitation, communications and transportation. Public Awareness Logistics The process of informing the public as to the nature of the hazard and actions needed to save lives and property prior A range of operational activities concerned with supply, to and in the event of a disaster. handling, transportation, and distribution of materials. Recovery Mitigation The coordinated process of supporting disaster affected Measures, structural and non-structural, taken to reduce communities in reconstruction of the physical infrastructure the impact of disasters. and restoration of emotional, social, economic and physical Or well being. “Structural and non-structural measures undertaken to Relief limit the adverse impact of natural hazards, environmental The provision of immediate shelter, life support and human degradation and technological hazards” needs of persons affected by a disaster. People-centered Approach Resilience While considering disasters as hazardous events, their The capacity of a system, community or society potentially occurrence is also viewed as the result of social, economic, exposed to hazards to adapt, by resisting or changing and environmental conditions and practices. People, their in order to reach and maintain an acceptable level of livelihoods & welfare are the central concern. functioning and structure. This is determined by the degree Preparedness to which the social system is capable of organizing itself to increase its capacity for learning from past disasters Arrangements to ensure that, should a disaster occur, all for better future protection and to improve risk reduction those resources and services which are needed to cope measures. with the effects can be effi ciently deployed. Resources or Any asset, physical, human, economic or environmental DWIDP Bulletin January 2014 Series XIV 26 which can be used to assist in achieving the objectives of Stakeholder the plan (people, equipment, relief supplies, water, roads, warehouses and money). Any one who has a vested interest or impacts on disaster risk management, either negatively or Response positively, and can include community members, local Actions taken in anticipation of, during and immediately and central government, land owners, private enterprise, after a disaster to ensure that its effects are minimized NGOs, Banks, development organizations, and the media. and that people affected are given immediate relief and support. Standard Operating Procedures Risk A set of directions detailing what actions could be taken, as well as how, when, by whom and why, for specifi c events The probability of harmful consequences, or expected or tasks. losses (deaths, injuries, property, livelihoods, economic activity disrupted or environment damaged) resulting from Support Agency interactions between natural or human-induced hazards Agencies that provide essential services, personnel, or and vulnerable conditions. Conventionally risk is expressed material to support a control agency or affected persons. by the notation; Risk = Hazards x Vulnerability. Some disciplines also include the concept of exposure to refer Technological Disasters particularly to the physical aspects of vulnerability. Beyond Disasters arising from other than natural disaster causes expressing a possibility of physical harm, it is crucial to and include biological, chemical, nuclear, transport and recognize that risks are inherent or can be created or exist terrorist instigated disasters. within social systems. It is important to consider the social contexts in which risks occur and that people therefore do Technological Hazard not necessarily share the same perceptions of risk and A hazard of a technological origin (man-made), as opposed their underlying causes. to a hazard of natural origin Risk Assessment Vulnerability A methodology to determine the nature and extent of risk A set of prevailing or consequential conditions composed by analyzing potential hazards and evaluating existing of physical, socioeconomic and/or political factors that conditions of vulnerability that could pose a potential adversely affect the ability to respond to disasters. threat or harm to people, property, livelihoods and the Vulnerabilities can be physical, social, or attitudinal and environment on which they depend. The process of can be primary or secondary in nature. Strategies that conducting a risk assessment is based on a review of both lower vulnerability also reduce risk. the technical features of hazards such as their location, intensity, frequency and probability; and also the analysis Or of the physical, social, economic and environmental dimensions of vulnerability and exposure, while taking The conditions determined by physical, social, economic particular account of the coping capabilities pertinent to and environmental factors or processes, which increase the risk scenarios. the susceptibility of a community to the impact of hazards. Risk Reduction Warning Systems Selective applications of appropriate techniques and The purpose of warnings is to persuade and enable people management principles to reduce either the likelihood of and organizations to take actions to increase safety and an occurrence or its consequences, or both. reduce the impacts of a hazard, which can be either quick onset i.e., cyclones, fl oods or slow onset, famine or man- Search and Rescue made such as fi res, explosion, chemical spills etc. The process of locating and recovering victims and the (Source: ISDR, IDRM Glossary of Disaster Risk application of fi rst aid and basic medical assistance as Management Terminology) may be required Situation Report A brief report which outlines the details of the emergency as they become known DWIDP Bulletin January 2014 Series XIV 27 Standards, Norms and Criteria: Hazard Categorization and Defi nition

Group Category Type Sub-type Meteorological Storm Wind storm e.g. Tornado, strong wind hazard Rain storm Extended rainfall Torrential rainfall Snow storm Hail/ice storm Dust/sand storm Thunder storm/lightning Cyclone Tropical cyclone Extratropical cyclone Extreme temperature Heat wave Cold wave Thermal shift? Freezing rain? Climatological El Nino / La Nina hazard Stream shutdown Ocean stream shutdown e.g. North Atlantic Gulf stream shutdown Sea level rise Slow-onset SLR Rapid-onset SLR e.g. Increasing melting of GLIS Extreme SLR e.g. Collapse of WAIS Glacier melting GLO Monsoon variation? Slow-onset M.V. * Global M.S., seasonality Rapid-onset M.V. Drought Meteorological drought Hydrological drought Agricultural drought Wildfi re Forest wildfi re Land wildfi re e.g. Bush, scrub, grass wildfi res Hydrological Flood Water-logging Due to extended rainfall and the low-lying topography hazard General fl ood By location (e.g. riverine, coastal, urban, underground), due to the capacity of drainage Flash fl ood Regular fl ash fl ood [By triggering events Mud fl ow (torrential rain, tsunami, Debris fl ow storm surge, GLOFs)] Tsunami seiche Storm surge Tidal wave Environmental Envi. degradation Desertifi cation hazard Deforestation Ecol. neglect Pollution Air pollution e.g. Acid rain, radioactive cloud & soot Surface water pollution e.g. Oil spill, effl uent contamination Groundwater pollution Waste disposal General waste disposal Toxic waste disposal DWIDP Bulletin January 2014 Series XIV 28

Geological hazard Earthquake Tectonic earthquake Inter-plate earthquake Intra-plate earthquake Volcanic earthquake Volcano eruption Lava fl ow Gas & aerosol Ashfall Mass movement Snow avalanche Dry snow avalanche Wet snow avalanche Landslide Landslide Rockslide Rockfall Debris avalanche Land subsidence Sinkhole Collapse Subsidence Soil liquefaction Expansive soil Erosion Coastal erosion Bank erosion Deposition Toxic chemical D. Planetary hazard Outer-space fallout Meteorite/asteriod Space debris Biological hazard Epidemic disease Viral infect. D. e.g. Avian fl u, swine fl u, N1H1, SARS, chicken pox, small pox, AIDS(HIV), Measles Bacterial infect. D. Parasitic infect. D. Fungal infect. D. Prion infect. D. Endemic disease Insect infestation e.g. Grasshoper/locust swarms/killer bees/mosquitos

Animal attack Animal stampede e.g. elephant Animal bite? e.g. dog Technological Accident Transportation e.g. car, boat, train, airplane, spacecraft, etc. hazard Explosion e.g. Boiling liquid, expanding vapour, hazardous chemical Fire e.g Electric fi re, spontaneous combustion Structure failure Dam failure Bridge failure Building collapse Other structure failure Equipment Equipment malfunction e.g. Design fl aw, illicit drugmaking & taking malfunction Anthropogenic Social unrest Confl ict e.g. crowd violence hazard Panic Plague Warfare e.g. guerrilla & civil war Terror attack e.g. criminal extortion by virus & poisons Hostage taking Hijacking Famine Economic crisis Economic recession Market collapse

(Source: Global Risk Identifi cation Programme- GRIP ) DWIDP Bulletin January 2014 Series XIV 31

Sensi sa on Workshop Dang River Bank Erosion Control Structure

Field Study of Trainees of 21st ACT Annual Progress Review Workshop, 2069/70

Emergency Work Porcupine Spur, Lakhandehi River, Sarlahi DWIDP Bulletin January 2014 Series XIV 32

21 st Advance Course Training Participants & DWIDP Officials

Department of Water Induced Disaster Prevention (DWIDP) Pulchowk, Lalitpur Post Box No. 13105, Kathmandu, Nepal Phone: 977-1-5535407, 5535503, Fax: 977-1-5523528 www.dwidp.gov.np