Compiled by: Er. Dipendra Gautam, strdyn@yahoo.com, Kantipur City College, Nepal

DEBRIS AND FLOOD CONTROL SYSTEM

• Flood: High amount of water flowing in streams often leading to flooding

• Debris flow: Sudden flow of soil and water mixture containing rocks/boulders as floating materials in viscous form

• NEPAL: Average annual precipitation 1700 mm (variable)

• 80% of rainfall between June to September

• High discharge during wet season

• Flash flood during winter season

• Fragile geology, annual torrential precipitation

#CAUSES OF FLOODING

• Deforestation

• Poor farming/haphazard farming

• Urbanization (high runoff, flash floods)

• Accelerated runoff at the base of mountain

• Sediment from erosion

• Overgrazing

#FLOOD MITIGATION

• Sustained action which eliminates long term risks of people and property from flood and their effects

• Measures for flood mitigation:

• 1. Structural measure

• 2. Non-structural measure

• 1. Structural Measures:

• Building dams, diversion, flood walls

• a. Drainage improvements

• b. Reservoir and detention

Compiled by: Er. Dipendra Gautam, strdyn@yahoo.com, Kantipur City College, Nepal

• c. Embankment, flood walls

• d. Diversion works

• 2. Non-Structural Measures

• To modify the susceptibility to flood damages, non-structural measures are taken. The structures are moved from floodways and flood plains. The main objective of this is to resettle people from river by:

• Flood plain management

• Flood forecasting and early warning

• Zoning

• Flood fighting

• Statistical analysis for high flood level

#ESSENTIAL COMPONENTS OF FLOOD PREPAREDNESS

• 1. PREPAREDNESS

• a. By concerned departments

• Pre-monsoon inspection of all tracks, canals, and drains for silt and debris clearance from seasonal rivulets

• Regular clearance of drains

• Regular maintenance of embankment of rivers, canal distribution

• Stored water clearance before monsoon

• Opening-closing of regulatory wares as per flood level

• Construction of communities, comprising of people from sectors like emergency service, vehicle, public transportation and district administration ensure proper coordination during crisis

• b. By central and district administration

• Review of contingency plans

• Update/modify it

• Coordinate with NGOs and local clubs

Compiled by: Er. Dipendra Gautam, strdyn@yahoo.com, Kantipur City College, Nepal

• Follow Dos and DON’Ts

• 2. RESPONSE MECHANISM

• Warning people

• Evacuating to safe place

• Relief action of the trapped people

• Search and rescue of missing ones

• Providing food, medical care, clothing, utensils, etc

• Post calamities measures

• Compensation to loss of life and their property

• 3. POST FLOOD ACTION

• Speeding restoration of roads, electricity and communication facilities

• Normalize water supply in the affected area by arranging water tankers or alternate means

• Repair communication lines, sewerage lines or priority so that life can be normalized

• Proper management of food supply, shelter, clothing

• Ensuring adequate supply of petroleum oil, kerosene and keeping the supply line moving

• Construction of survey team to access loss and compensation to the victims

• Assistance for repair and rebuilding

• Desilting and dewatering of the affected area