1. Determination of capacity of reservoir &volume from borrow pit
SIDDHANT VERMA
VATSAL KATARIYA
YESHA PATEL
GROUP NUMBER-19

2. Definition of reservoir
A reservoir (etymology: from French réservoir a "storehouse" is a natural or artificial lake, storage pond, or impoundment from a dam which is used to store water.
Reservoirs may be created in river valleys by the construction of a dam or may be built by excavation in the ground or by conventional construction techniques such as brickwork or cast concrete.
The term reservoir may also be used to describe naturally occurring underground reservoirs such as those beneath an oil or water well.

3. reservoir damned in valleys
types of reservoir
reservoir damned in valleys
A dam constructed in a valley relies on the natural topography to provide most of the basin of the reservoir.
Dams are typically located at a narrow part of a valley downstream of a natural basin.
The valley sides act as natural walls with the dam located at the narrowest practical point to provide strength and the lowest practical cost of construction.
In many reservoir construction projects people have to be moved and re-housed, historical artifacts moved or rare environments relocated.
Examples include the temples of Abu Simbel ( which were moved before the construction of the Aswan Dam to create Lake Nasser), the re-location of the village of Capel Celyn during the construction of Llyn Celyn,
And the relocation of Borgo San Pietro of Petrella Salto during the construction of Lake Salto.

4. BANK SIDE RESERVOIR
Where water is taken from a river of variable quality or quantity, bank-side reservoirs may be constructed to store the water pumped or siphoned from the river.
Such reservoirs are usually built partly by excavation and partly by the construction of a complete encircling bund or embankment which may exceed 6 km in circumference.
Both the floor of the reservoir and the bund must have an impermeable lining or core, initially these were often made of puddled clay, but have generally been superseded by the modern use of rolled clay.
The water stored in such reservoirs may have a residence time of several months during which time normal biological processes are able to substantially reduce many contaminants and almost eliminate any turbidity.
The use of bank-side reservoirs also allows a water abstraction to be closed down for extended period at times when the river is unacceptably polluted or when flow conditions are very low due to drought.

5. SERVICE RESERVOIR
Service reservoirs store fully treated potable water close to the point of distribution. Many service reservoirs are constructed as water towers, often as elevated structures on concrete pillars where the landscape is relatively flat.
Other service reservoirs are entirely underground, especially in more hilly or mountainous country. A good example is the Honor Oak Reservoir, constructed between 1901 and 1909.
When it was completed it was the largest brick built underground reservoir in the world and is still one of the largest in Europe.
The reservoir now forms part of the Southern extension of the Thames Water Ring Main.
Service reservoirs perform several functions including ensuring sufficient head of water in the water distribution system and providing hydraulic capacitance in the system to even out peak demand from consumers enabling the treatment plant to run at optimum efficiency.

6. Determination of capacity of reservoir
The plane containing any contour,represents a horizontal plane and area bounded by contour is treated as area of cross section.
The area bounded by contour is measured by planimeter.
A contour map is very useful to study possible location of a reservoir and volume of water to be confined.
In practice,the capacity of a reservoir is measured in terms of volume of water stored upto full reservoir level(FRL) which is level of water at its full capacity.

7. Method to compute volume of reservoir
TRAPEZOIDAL FORMULA
According to end-area formula,the volume between two cross-sections having areas A1 and A2.
V=1/2(A1+A2)*D
where,D is the distance between two sections.For a series of cross-sections at a regular interval of D ,the total volume.
V=D/2[(A1+A2)+2(A2+A3+A An-1)]
'n' is the number of segments in which the total length L between the end areas has been divided i.e. L=ND.

8. PRISMOIDAL FORMULA
When the more exact volume is required to be computed,the prismoidal formula ay be used.
V=2d/6(A1+4m+A2)
A1 and A2 are two end cross-sections at a disance of 2d.
M=the area of middle section.
If sections A1,A2,A3,A4,.....an arc at a regular interval of d,the volume between sections A1 and A3 will be
V1-3=d/3[A1+4A2+A3]
In general,prismoidal formula can be written as,
V=d/3[A1+An+4(A2+A4+An-1)+2(A3+A An-2)]

9. Definition of borrowpits
A borrow pit, also known as a sand box, is a term used in construction and civil engineering. It describes an area where material (usually soil, gravel or sand) has been dug for use at another location. Borrow pits can be found close to many major construction projects. For example, soil might be excavated to fill an embankment for a highway, clay might be excavated for use in brick-making, gravel to be used for making concrete, etc.
In some cases, the borrow pits may become filled with ground water, forming recreational areas or sustainable wildlife habitats (one such example is the Merton Borrow Pit, near Oxford in central England, excavated to provide materials for the nearby M40 motorway). In other cases, borrow pits may be used for landfill and waste disposal.

10. purpose of borrowpits
There are many things that can be done with a borrow pit once a construction crew has finished digging inside of the initial hole.
Some pits are used as landfills, while other pits may form recreational areas. In fact, it is not uncommon for a municipality to fill a pit with water, resulting in a small manmade pond or a large lake.
Other pits may be turned into wildlife habitats by adding certain elements, such as water, to the pit area. Rarely do municipalities decide to fill a pit in with extra sand or other material, though this is possible.

11. things to be kept in mind while digging borrowpits
The digging of a borrow pit falls under the engineering discipline known as earthworks. Earthworks projects consist of engineering feats that include transporting large amounts of soil or rock from one area to another. Borrow pit construction may seem relatively easy to accomplish, though this type of digging actually requires an extensive amount of analysis prior to the first dig.
Engineers must be sure that the amount of soil dug from a pit area will not disrupt the earth. This specific type of engineering, called geotechnical engineering, is a complex process. Prior to the invention of the computer, geotechnical engineers were forced to calculate the degree to which the earth would shift during digging by hand. Today, computer programs make these types of calculations simpler.

12. computation of volume of borrowpits
In the method to evaluate volume of borrowpits area is divided into regular figures such as squares,rectangles or triangles and levels of corners of the figures are measured before and after the construction.
The corners of figures may be at different elevation but lie in the same plane.
The earth to be moved will be a right truncated prism.If depth of cuts are p1,q1,r1 and s1 respectively,and A is the area of figure pqrs then volume is given by:-
V=BASE AREA*MEAN HEIGHT

13. VOLUME OF GROUP OF RECTANGLES OR SQUARES HAVING SAME AREA
Let us consider a group of rectangles of same area,arranged as shown in figure.It will be seen by inspection that some of the heights are used once only some heights are common to two rectangles some heights are common to three rectangles and some heights are common to four rectangles .Each corner height will be used as many times as there are rectangles joining at corner.
Total volume is given by:-
V=A(1

14. VOLUME OF A GROUP OF TRIANGLES HAVING EQUAL AREA
If ground is very much undulating,the area may be divided into a number of triangles having equal area.In this case,some corner heights will be used once,a some twice,thrice,four times,five times,six times,and seven times.The maximum number of times a cornerheight can be used is eight.
Each corner height will be used as many times as there are triangles joining at corner.
V=A/3[ ]

15. THANK YOU