GULLY CONTROL GULLY CONTROL MEASURESMEASURES

RICHA RAI (39)RICHA RAI (39)

NATURAL RESOURCE MANAGEMENT

IntroductionIntroductionWhat is Gully?What is Gully?Gullies are the landform that are Gullies are the landform that are

created by running water eroding created by running water eroding sharply into a hillsides.sharply into a hillsides.

How gullies are formed?How gullies are formed?Gullies are generally formed by an Gullies are generally formed by an

increase in surface runoff.increase in surface runoff.

Areas of ConcernAreas of Concern

Reduction in cultivable landReduction in cultivable land Increased velocity of run-off Increased velocity of run-off

waterwater Reduces storage capacity of Reduces storage capacity of

reservoirs and dams.reservoirs and dams. Source:www.fao.orgSource:www.fao.org

FACTORS AFFECTING GULLY FACTORS AFFECTING GULLY FORMATIONFORMATION

MAN-MADE FACTORSMAN-MADE FACTORS1.1. Improper land useImproper land use2.2. Forest and grass firesForest and grass fires3.3. OvergrazingOvergrazing4.4. MiningMining5.5. Road constructionRoad construction6.6. Livestock and vehicle trailsLivestock and vehicle trails7.7. Destructive loggingDestructive logging

Physical FactorsPhysical Factors

PrecipitationPrecipitationa)a) Monthly distribution of rainfallMonthly distribution of rainfallb)b) Rainfall intensity and run-offRainfall intensity and run-offc)c) Rapid snowmeltsRapid snowmelts TopographyTopographya)a) Shape of catchmentShape of catchmentb)b) Size of catchmentSize of catchmentc)c) Gradient of the slope.Gradient of the slope.

Soil propertiesSoil properties

Vegetative coverVegetative cover

Criteria for selecting control Criteria for selecting control measuresmeasures

1.Gully catchment area1.Gully catchment area – the larger the – the larger the area is ,the greater will be the area is ,the greater will be the surface runoff. Thus more water will surface runoff. Thus more water will enter the gully which may further enter the gully which may further make the case worst. So, large make the case worst. So, large structures are preffered to stop this structures are preffered to stop this incoming water like check dams. incoming water like check dams.

2.The Gradient2.The Gradient

The steeper the slope will be the The steeper the slope will be the greater will be the speed with which greater will be the speed with which water will flow, more speed of water water will flow, more speed of water may lead to more erosion of soil, so may lead to more erosion of soil, so those structures should be made that those structures should be made that can reduce the speed of incoming can reduce the speed of incoming water.water.

3.Length of the gully channel3.Length of the gully channel

If the length of the gully channel will If the length of the gully channel will be large than with due time the be large than with due time the speed of the water flowing in it will speed of the water flowing in it will get reduce, on other hand if the get reduce, on other hand if the length of gully will be small the length of gully will be small the chances of erosion increases.chances of erosion increases.

Types of Control MeasuresTypes of Control Measures

MechanicalMechanical: Any earthern, stone or : Any earthern, stone or masonry structure constructed masonry structure constructed across the slope. across the slope.

VegetativeVegetative: Any live bund or : Any live bund or vegetation established across the vegetation established across the slope.slope.

Vegetative Filter StripsVegetative Filter Strips

Stripes of plant Stripes of plant speciesspecies

Reduces velocity of Reduces velocity of water flow, water flow, arresting silt.arresting silt.

Adoptable in all Adoptable in all areas irrespective areas irrespective of soil and rainfallof soil and rainfall

Semi-permanent Semi-permanent vegetative vegetative measuremeasure

plantandsoil.unl.edu/.../siteImages/P325LG.jpg

Brush wood check damsBrush wood check dams

Driving wooden Driving wooden pegs into the groundpegs into the ground

Intertwining brush Intertwining brush woodwood

Adoptable in all Adoptable in all areasareas

Semi permanent Semi permanent mechanical & mechanical & vegetative measure.vegetative measure.

www.fao.org/DOCREP/006/AD082E/images/3_3.jpg

Loose Boulder Check DamsLoose Boulder Check Dams

Porous checksPorous checks Loose bouldersLoose boulders Adoptable in all Adoptable in all

areasareas Semi permanent Semi permanent

mechanical mechanical measure.measure.

www.fao.org/DOCREP/006/AD082E/images/3_9.jpg

Percolation TanksPercolation Tanks

Embankments Embankments across natural across natural depressions in depressions in arable, non-arable arable, non-arable and community and community lands.lands.

Recharges ground Recharges ground waterwater

Permanent Permanent mechanical mechanical measuresmeasures

raigarh.nic.in/images/jal6.jpg

Gabion StructuresGabion Structures Wire woven baskets Wire woven baskets

filled with stonesfilled with stones Trap erosion debris Trap erosion debris

during heavy rains in during heavy rains in active gulliesactive gullies

Adoptable in high Adoptable in high slope & heavy rainfall slope & heavy rainfall areas conducting areas conducting high velocity runoff, high velocity runoff, carrying large carrying large sediments and sediments and cutting of banks.cutting of banks.

Semi permanent Semi permanent mechanical measuremechanical measure

www.chandla.com/image/new1/poto19.gif

Rubble DamsRubble Dams

Rubble (A loose Rubble (A loose mass of angular mass of angular fragments of rock ) fragments of rock ) obstructions.obstructions.

Adoptable in all Adoptable in all areasareas

Semi permanent Semi permanent mechanical mechanical measuremeasure

www.cr.nps.gov/.../graphics/Roosevelt1.jpg

CHUTE SPILLWAYCHUTE SPILLWAY

Open channels with steep slopes

Consist of Inlet, vertical curve section, steep slope channel & outlet

Constructed in areas of steep slopes & sudden drops

Permanent mechanical measure

statelibrary.vic.gov.au/.../0/1/im/rw001931.jpg

Nala BundsNala Bunds

Earthen Earthen embankments across embankments across nalanala

Regulates excess Regulates excess flow through channelflow through channel

Adopted in low to Adopted in low to medium rainfall medium rainfall areasareas

Permanent Permanent mechanical measuremechanical measure

kar.nic.in/watershed/nala_bund.jpg

Drop StructureDrop Structure

Dams constructed Dams constructed across nalaacross nala

Excess run off Excess run off passes through weirpasses through weir

Check water velocity Check water velocity & permit storage& permit storage

Permanent Permanent mechanical measuremechanical measure

www.ars.usda.gov/images/docs/5537_5721/dec2.gif

ReferencesReferences

http://www.fao.org/DOCREP/006/http://www.fao.org/DOCREP/006/AD082E/AD082e02.htmAD082E/AD082e02.htm

Information kit produced by MYRADA Information kit produced by MYRADA and the International Institute of and the International Institute of Rural Reconstruction.Rural Reconstruction.