A short note to establish a water supply scheme in urban or rural area.

A short  note to establish a water supply scheme in urban or rural area.

Prefatory

WATER SUPPLY & DRAINAGE

In the world of Disraeli " The health of the people is really the foundation upon which their happiness and all their powers as a State depend " It is obvious how environmental sanitation reflects on the promotion and maintenance of the health of the people .

     The provision of a safe adequate water supply is a basic requirement, the importance of which cannot be over emphasized, and this remark applies with special reference to a tropical country like India which is subject to epidemic waves of water borne diseases of great magnitude .

   The provision of pure water and proper disposal of sewage are two essential for improving the living condition of the people and ensuring their good health.

INVESTIGATION  FOR WATER SUPPLY SCHEMES

KEY PLAN:-

A key plan should be prepared to a foolscap size showing the town, the various sites proposed for the head-works, service reservoirs connecting roads, rivers or stream course etc . and other relevant features  of the area covered.

INDEX PLAN

An up-to-date town plan should be prepared to a scale of 1cm: 40M showing

(1)    The Corporation,  Municipal , or panchayat limits and any extension or future under completion shown in distinguishing coloures .

(2)    Levels at junctions od road, streets and lanes and also at the places in the road where the gradient change. The ward boundaries as taken for the purpose of the latest census, must be marked and the population figures noted there in.

BENCH MARKS

Permanent bench marks stones should be fixed at the intervals of not less than 1.5 KM and not more than 2.5 KM . Bench Marks stones should also be fixed at the site of the Head Works and Service Reservoir site . The permanent Bench marks  should be fixed based on the level of SBM stone under the control of department concern particularly under the control of the Public Works & Highways Department on confidential.

LEVELING OPERATIONS

Longitudinal section should be taken along the suitable and convenient alignment in roads, streets, and lanes for laying distribution , pumping and gravitational mains In the case of pumping mains, alternative alignment on cross countries must also be considered and levels taken. Detailed plans, sections of drainage streams , canals bridges culverts, whatever the mains are to be taken across must be prepared.

SURVEY PLANS AND SECTIONS

(a)    A key plan

(b)   An index plan showing the levels at junctions of roads , site of Service Reservoir, and ward boundaries with respective figures of populations, tha position of public fountains required in the town fixed in consultation with Corporation Municipal or Panchayat authorities.

(c)    Plan showing the Sanitary Bench Marks.

(d)   Emlarged survey plans showing there in clearly the various survey numbers comprising Head Works , houses, staff quarters, filtration plant etc. plotted to a large section.

(e)   Land plans and schedule for acquisition of site required for the schemes. If land is patta land  the consent letter of the owner of the land will be received or compulsory land acquisition proposals will be sent to the department consent, particularly Revenue Department to acquire the land as per the rules and regulations of the Government. 

(f)     Enlarged site plan of the Service reservoir as required.

(g)    Longitudinal levels for all streets, roads, lanes, alignment of pumping main Gravitational main and distribution mains plotted to a scale of !cm:40Mt longitudinal and 1cm: 1Mt vertical.

(h)   Cross section of streets and drain crossings.

(i)      L.S and cross sections of borings at the site of head works showing the different strata  M.F.L , N.W.L , L.W.L observed so far, besides individual sections of borings.

(j)     A site plan showing the position of borings put in during the nature of soil and their respective distances from each other and permanent object perfectly with bearings.

(k)    L.S. along the syphon pipe line or Connecting pipes showing natere os soil and sub-soil and water level ( N.W.L. H.W.L, and L.S.W.L.) along the lines as revealed by bearing put to along the alignment.

TRIAL PITS

At site of pump house, staff quarters , filtration plants, Service Reservoir trial pits shall be put down at suitable intervals and and nature of the soils, sub-soils, water levels etc. should be noted in the respective site plans in which the exact position of the trial pits should be marked.

BORINGS

Sufficient number of borings must put down at the site selected for infiltration works with a view to obtain a complete hydrological and geological survey of the whole area. Selection of borings must be plotted with the particular of soil and sub-soil condition.

LEVELING OPERATIONS:

1.Longitudinal section levels should be taken at the centre of all road , streets and lanes at 30Mt intervals and at junctions of all roads, streets, and lanes recording width of roads streets and lanes at every changes of width, information’s  as to whether metaled or not . The number of houses on either side of the streets upto junctions of another streets or lane.

2. SPOT levels for the sites of pump house , treatment works and sewage farm should be taken. Particulars or M.W.L Normal eater leval, lower summer water level and Bed level of nearby drain, channel or rivers should also be gathered.

TRIAL PITS

At the site of pump house, Treatment works, sewage farm and along tha alignment of main sewer trial pits should be excavated and the particulars as the nature of the soil and water level should be collected. Paticularly at pump house and along the alignment of Main sewers Borings should be put down for a depth of 5 meters.

Quarry map and lead statement should be prepared.

A-     WATER SUPPLY SOURCES NATURE SECTION

Water supplied as surface and ground water supplies.  The suface supplies are either from running streams such as rivers or from quiescent waters such as lakes natural or artificial. The ground water supplies are obtained from springs, Infiltration wells or galleries.

The usual contaminants of water are mineral or organic nature. The mineral dead organic matter may be present in solution or in suspension living organic may be micro or migro-organisms. The micro-organisms may be plankton or bacteria. The former are to the Zoo or phyto plankton according to whether they belong to animal or plant Kingdom. Bacteria are unicellular plant which multiply by fission. They can grown on a culture medium and are studied with difficulty under microscope. Plankton do not need a culture and can be easily studied under a microscope. In general bacteria make water unsafe while plankton render water unpleasant.

The main aim in purification of water used for drinking purposes is to make the water safe as free  from the microbes which cause disease and to bring down the content of the other matter to a limit of toleration compactable with the sense of aesthetics. The main criterion for an industrial water supply is the maximum content of the various constitutes chiefly minerals, the bacterial content being of a minor importance.

That branch of science which deals with the properties and characteristics of stream or flowing water is called Rheology and that which deals similarly with quiescent waters such as lakes is called Limnology. The physical, chemical and biological conditions of a all interrelated . The public health Engineer has to consider all the aspects of the nature of source and its bearing of the water quality to desiren the best method of purification , necessary in any case.

The selection of source for a place is depend on its reliability to yield adequate quantity of water according to demand and of water fit for the particular use cantailing the least amount for the works connected with collection , purification , conveyance and distribution.