Discuss types of gully control measures. Only engineering measures are discussed in detail.

1. Gully Control Measures
By:- Er. Gurpreet Singh

2. Gully Control Measures
Gully Control Measure
Biological/Vegetative Measure
1. Sod Flumes
2. Changing Gully in grasswater
ways
3. Anti-erosion crop
4. Sod Strip
5. Tree, Shrub
Engineering Measure
1. Temporary Gully Control
2. Permanent Gully Control
Source:- Google, notes and Books

3. Design of Permanent Structure
• The design of the gully erosion control structure involves
1) Hydrologic design
2) Hydraulic
3) Structural Design

4. Permanent Structure
• Three Basic type of permanent structures that are employed for stabilizing
gullies
1. Drop spillway
2. Drop inlet spillway
3. Chute spillway
• Used in gullies with medium to large drainage area, i.e in situations where
temporary structure may fail.
• Usually built of masonry or reinforced concrete.
• Proven measures for efficieny erosion control in any soil and conservation
program.
Source: Books

5. Inter-comparison
• Drop-spillway: Drop < 3m upstream storage – No
• Drop-inlet spillway Drop > 3 m upstream storage – Yes
• Chute Spillway > 3m upstream – No
Source: Books, google

6. Functions
• The should handle the peak runoff at safe velocity.
• The should be able to stabilize the gully.
• The should store the water for irrigation and other purposes.
• The sediment flow should be controlled.

7. Purpose of designing Gully Control
• Gully stabilisation
• Soil erosion control
• Sediment Control
• Water conservation
• Flood control
• Drainage

8. Planning for Design
• Permanent structure are constructed when the benefits from such structures
are justification compared to the cost of construction.
• The design after careful investigation of
• Various factors influencing the characteristics of runoff
• The downstream flow characteristic
• Other specific requirement
• An analysis of all the factors affecting the work.
• No standard solution which applied for all problems

9. Drop Spillway
• It is a weir structure, in which flow passes through the weir opening, falls
on the apron and then passes in to the downstream.
Source: Books, google

10. Functions of components
• Head wall: It acts as a front wall against runoff in the drop spillway.
• The size of the weir should be sufficient to pass the design discharge safety.
• Head wall extension: Permit stable fill and prevents piping.
• Sidewall: Guide the water and protect the fill against erosion.
• Wing wall: Provide stability to fill and give protection to gully bank and surface.
• Apron: Dissipates the kinetic energy of falling water by creating hydraulic jump.
• Longitudinal skill: Provide stability to the apron.
• End sills: Its main function is to obstruct the water from going directly into the channel
below.
• Cut-off wall: Prevents piping under the structure besides reducing uplift and preventing
sliding.
• Toe wall: Prevents undercutting of apron.
Source: Books

11. Use of drop spillway
• To control gradient in either natural or constructed channel.
• To serve as reservoir spillway where the total drop in relatively low.
• To control tail-water at the outlet of a spillway or conduit.
• To serve as inlet and outlet structures for tile drainage system.

12. Drop-Inlet Spillway
• Where the inlet is funnel shaped this type of structure is often called as Morning
glory/Glory hole.
Discharge Characteristics
• Discharge characteristics varies with the range of head.
• As long as the outflow through the box remains less than the capacity of
pipe.
• When the outflow at the box exceeds the capacity of the pipe, the box inlet
fills and the discharge is then governed by the pipe capacity.

13. Advantages
• Stability
• It is very stable structure and likelihood of serious structural damage is remote.
• Non-clogging of weir
• Rectangular weir, which is used in this case
• Ease & economy of construction.
• Low maintenance cost.
• Standardization.
Disadvantages
• Maximum drop is limited to 3m
• It is not a favourable structure where temporary spillway storage is desired
to obtain large reduction in the discharge.

14. Chute Spillway
• A chute spillway is a steeply sloping open channel, which leads the water
from a channel, which leads the water from higher elevation to the
downstream.
• The chute is sometimes of constant width but is usually narrowed for
economy and they widened near the end the reduced the discharge velocity.
• The slope of the chute must conform to the slope at the site, longitudinal
and cross section survey at the site.
•Applicability
• Used when the drop exceed 3 m
• Superior to drop-inlet spillway for large discharge.
• Preferred over drop-inlet spillway when there is no opportunity to provide
temporary storage.

15. Disadvantage
• There is a considerable danger of undermining due to additional precaution
are required to handle this problem.
• In poorly drained areas, there is a problem of seepage
• Such areas may not be suitable for chute spillway as seepage tends to weaken
foundation
• Constructing chute spillway is essential and no other substitutes are available.

16. Temporary Gully
• It is for gully control, construction of brush, wood, rocks, woven wire and
sod/earth.
• It is used where material locally available and labour is cheap.
• It is helpful during the establishment of vegetation.
• Main purpose to control the erosion
• It is suitable with small drainage areas.
• Helpful for collecting soil and conserve moisture in guly bottom for the
growth of vegetation.
• A grade of 0.1 to 0.5% is provided.

17. Temporary Gully Control
1. Brush Dams
2. Loosen Rocks Dams
3. Plank/Slab Dam
4. Log and Pole Dams

18. Thanks