Download - Groundwater Quality mapping

Ground Water Quality

Mapping

Background of GWQ mapping

Under Rajiv Gandhi National Drinking Water Mission

(RGNDWM)-Operational project sponsored by Ministry of

Drinking Water & Sanitation, Govt. of India

Maps are expected to serve as a database for identifying

potable GW sources & locations for site-specific RS for

supplying drinking water to rural habitations

National Remote Sensing Centre / ISRO in collaboration

with various Central & State Govt. Departments

as Partner Institutes

Executed

by

Mode of

execution

Scope of

the data

Creation of spatial data base on ground water quality

in the form of ground water quality maps for entire country

Objective

Pre - monsoon

Post - monsoon

Origin of contamination - Geogenic

and anthropogenic origin

Source of contamination - Point and

Nonpoint sources

Governing factors

of contamination – Chemical &Physical

properties of Geological material

Concentration of

contaminants - changes

with recharge

Contaminants

concentration – high at min

WL & low at max WL

GWQ in terms of space GWQ in terms of time

Unit of factors governing

contamination - Aquifer

Background Concept

Aquifers (Shallow and deep aquifers)

Ground water zones (Dynamic and Static zones)

Depth - wise analysis Season - wise analysis

Unit of factors governing

change in concentration -

Aquifer

Ground water quality mapping methodology flow chart

Organized Legacy data

excel table Analysis,

Interpretation &

Organization

Interpolation

using statistical

method

Parameter-wise ground

water quality layers

Ground water quality

point data layer

Legacy GWQ data

Fresh GWQ data

Lat-Long data

Satellite Data

Habitation data

Integrated ground


Inte

rme

dia

te

ou

tpu

ts

Ground water

quality point

data layer

Inte

rme

dia

te

ou

tpu

ts

Parameter-wise

ground water

quality layers

Grouping &

Union of layers


map (corresponding to

1:50,000 scale toposheet)

Inte

rme

dia

te

ou

tpu

ts

Integrated GWQ

layers, Base map

layers

Fin

al

ou

tpu

t

Validation, Map

composition &

Clipping

Input data Process Output data

Outputs generated

Organized input Legacy ground water quality data

Excel format

E00 file & shape file format

Ground water quality data point layer

Parameter-wise

Ground water quality layers

(Depth & Season-wise)

Integrated Ground water quality layers

(Depth-wise)


map of entire study area


map corresponding to

1:50,000 scale toposheet

Mxd file format

Tabular Data-

Intermediate

output

Layers-

Intermediate

output Maps-

Final output

Legacy ground water quality data

Legacy ground water quality data – Formatting

Data collection – ensured collection of all the available data

Excel table structure – Followed classification system & standards

Redundant data points elimination – Apply criteria for identifying duplicate points

Location Description Depth of well Date of sample

collection Ground water quality data

Dri

nk

ing

wa

ter

so

urc

es

Legacy ground water quality data –

Elimination of redundant data points

Example of Allagi-B habitation

Elimination of redundant data points – Based on identification of duplicate points


Dummy point features – Criteria followed;

RGNDWM habitations’ geospatial position as a reference

Point

data

Datum & Projection of layer – WGS 84 Datum & LCC / TM Projection

as applicable to given state

Field name Field type Key(Y/N) Remarks

GWQWL-Code 2,2,C Y Feature code

D-Name 25, 35 , C N District Name

B-Name 25, 35 , C N Block Name

P-Name 25, 35 , C N Panchayat Name

V-Name 25, 35 , C N Village Name

H-Name 25, 35 , C N Habitation Name

L-Name 25, 35 , C N Location Name within habaitation

GWQWL-Depth 25, 35 , C N Depth of well / Type of the well

GWS-Date 10, 10 , C N Date of ground water sample collection

CaCo3 4,4,C N Concentration of CaCo3 in water sample

Fe 4,4,C N Concentration of Fe in water sample

SYM-CODE 2,2,I N Symbol code for representing the wells


GWQWL-Code GWQWL-Depth

01 Open dug / ring well

02 Dug-cum-bore / tube well

03 Bore / tube well with power pump

04 Bore / tube well with hand pump

Numeric codes to be used for representing type of well

Data base structure

Attribute

data

Depth-wise segregation

of legacy ground water quality data points Criteria for Depth-wise segregation –

i) Vertical variations in hydrogeomorphic units

ii) Ground water zones

Hydrogeomorphic unit-3

Hydrogeomorphic

unit-1

Hydrogeomorphic unit-2

Ground water zone 2

Ground water zone 1 Ground water zone 1 Ground water zone 1 Shallow depth zone

Deeper depth zone

Depth-wise segregation

Season-wise segregation

of legacy ground water quality data points

Criteria for season-wise segregation –

Date of ground water sample collection

Criteria for identification of periods of seasons in the given region / state –

Minimum & Maximum water level data;

minimum stands for pre monsoon & maximum stands for post monsoon season

Density of ground water quality data points –

Representative 20 to 25 points in an area of 700 sq km

(1:50, 000 scale toposheet area)

Geospatial position of ground water quality data points –

Latitude Longitude data collected using good accuracy (+/- 10m) GPS

Distribution of ground water quality data points –

Uniform through out the mapping unit

Authenticity of ground water quality data points –

Validation with FTK ground water quality data

Mapping unit-wise

ground water quality data point layer

Point

data

Area where there are no ground water quality data points –

Carve out as separate polygons not to take in to account

Datum & Projection of layer –

WGS 84 Datum & LCC / TM Projection


Mapping unit-wise

Ground water quality point data layer

Quality parameter-wise Ground water quality layer

(of APO-12 aquifer)

(with automatic classes)

Sl. No

Element

Potable

Non-

Potable Desirable limit Permissibl

e limit

1 pH 6.5 to 8.5 -- <6.5 to >8.5

2 Total Hardness (as CaCo3) mg/l 0-300 300-600 > 600

3 Iron (as Fe) mg/l 0.0 0.3 0.3-1.0 > 1.0

4 Chlorides (as Cl) mg/l 0-250 250-1000 > 1000

5 Total Dissolved solids mg/l 0-500 500-2000 > 2000

6 Bicarbonate (as MG) mg/l 0-500 -- > 500

7 Calcium (as Ca) mg/l 0-75 75-200 > 200

8 Magnesium (as Mg) mg/l 0-30 30-100 > 100

9 Nitrate (as NO3) mg/l 0-45 45-100 > 100

10 Sulphate (as SO4) mg/l 0-200 200-400 > 400

11 Fluoride (as F) mg/l 0.0 1.0 1.0-1.5 > 1.5

12 Manganese (as Mn) mg/l 0.00-0.10 0.10-0.3 > 0.3

13 Sodium (as Na) mg/l -- -- --

14 Potassium (as K) mg/l -- -- --

15 Arsenic (as As) mg/l 0.00-0.05 -- > 0.05

16 Phenolic Compounds (as C 6H5OH)

mg/l 0.000-0.001 0.001-0.002

> 0.002

17 Mercury (as Hg) mg/l 0.000-0.001 -- > 0.001

18 Cadmium (as Cd) mg/l 0.00-0.01 -- > 0.01

19 Selenium (as Se) mg/l 0.00-0.01 -- > 0.01

20 Copper (as Cu) mg/l 0.00-0.05 0.05-1.5 > 1.5

21 Cyanide (as CN) mg/l 0.00-0.05 -- > 0.05

22 Lead (as Pb) mg/l 0.00-0.05 -- > 0.05

23 Zinc (as Zn) mg/l 0-5 5-15 > 15

24 Anionic detergents (as MBAS) mg/l 0.0-0.2 0.2-1.0 > 1.0

25 Chromium (as Cr6+) mg/l 0.00-0.05 -- > 0.05

26 Polynuclear aromatic hydro

carbons (as PAH) mg/l 0.0-0.2 --

> 0.2

27 Mineral Oil mg/l 0.00-0.01 0.01-0.03 > 0.03

28 Pesticides mg/l 0 0-0.001 > 0.001

29 Radioactive Materials α emitters pci/l 0 0-0.1 > 0.1

30 Radioactive Materials β emitters pci/l 0 0-1.0 > 1.0

31 Alkalinity mg/l 0-200 200-600 > 600

32 Aluminium (as Al) mg/l 0.00-0.03 0.03-0.2 > 0.2

33 Boron mg/l 0-1 1-5 > 5

Criteria used

for classification

of ground water

quality -

Bureau of

Indian Standards

(BIS)

Quality parameter-wise Ground water quality layer

(of APO-12 aquifer)

(with classes as per BIS Standards)

Element-wise

ground water quality layer Alphabetical code

to be used for the layer

Ground water quality layer of CaCo3 in

shallow aquifer of pre-monsoon GWQ Layer-CaCo3-Sh-Pr


shallow aquifer of post-monsoon GWQ Layer-CaCo3-Sh-Po


deep aquifer of pre-monsoon GWQ Layer-CaCo3-Dp-Pr


deep aquifer of post-monsoon GWQ Layer-CaCo3-Dp-Po

Ground water quality layer of Fe in

shallow aquifer of pre-monsoon GWQ Layer-Fe-Sh-Pr


shallow aquifer of post-monsoon GWQ Layer-Fe-Sh-Po


deep aquifer of pre-monsoon GWQ Layer-Fe-Dp-Pr


deep aquifer of post-monsoon GWQ Layer-Fe-Dp-Po

Naming conventions to be followed - Alphabetic codes

Field Name Field Type Key (Y/N) Remarks

GWQ-Value 11, 11, C Y Numerical value (as range) indicating

concentration of the element in ground water

GWQ-Code 2, 2, C N Numerical Code indicating ground water quality

class i.e Potable, Permissible, Non-Potable

SYM-Code 2, 2, I N Symbol code for representing ground water

quality class in the map

Quality Parameter-wise ground water quality layers

Numerical Codes to be used for representing different ground water classes

Sl. No. Water quality class Numerical code

1. Potable water with desirable limits 01

2. Potable water with permissible limits 02

3. Non-potable water 03

Symbol Codes to be used for representing different ground water classes

Polygon features Symbol Code Symbol

Potable water with desirable limits 1

Potable water with permissible limits 2

Non-potable water 3

Data base structure

Attribute

data

Integrated ground water quality layer layers

Polygon

data

Datum & Projection of layer –

WGS 84 Datum & LCC / TM Projection


Criteria followed for classification of ground water quality –

Derivative combined quality

Number & kind of integrated ground water quality layers derived –

Separate layers for separate depth zones;

Shallow & deeper depth zones

Criteria followed for dissolving duplicate units –

i) Units in which no GWQ data points,

ii) Contiguous units having same quality,

iii) Narrow units occurring in the periphery of large polygons,

iv) Very small units occurring in isolation within the large units

Accuracy of ground water quality units –

Validation using data points of ground water quality data point layer

Field name Field type Key (Y/N) Remarks

GWQ-Code 2,2, C Y Numerical code indicating ground water quality

class is to be given. (refer table-11)

PGWQ-Value 100, 100,C N Alpha-numeric code indicating element-wise

ground water quality, as value, is to be given.

eg. Fe-1.0 mg/l, TDS-1500 mg/l, ….. As-0.01 mg/l

‘Pr’ or ‘Ps’ may be added as pre-fix to indicate the

season respectively.

PGWQ-Code 100, 100,C N Alpha-numeric code indicating element-wise

ground water quality, as class, is to be given.

eg Fe-1, TDS-2, …….As-1‘Pr’/‘Ps’ may be added

as pre-fix to indicate the season respectively.

SYM-Code 2,2, I N Symbol code (colour scheme) for representing

ground water quality in the map is to be given.

Integrated ground water quality layer

Numerical Codes to be used for representing different ground water classes

Sl. No. Water quality class Numerical code

1. Potable water with desirable limits 01

2. Potable water with permissible limits 02

3. Non-potable water 03

Data base structure

Attribute

data

Ground water quality map (Regional / State / Corresponding to 1:50,000 scale SOI toposheet)

Map part

Ground water

quality units

Base map details

Aquifer units

Column 1- Map Unit

Column 2- Aquifer unit description

Column 3- Pre monsoon Ground water quality

Column 4- Post monsoon Ground water quality

Column 5- Constituents analyzed

Column 6- Anomalous constituents

Column 7- Remarks

GWQ Data – Stages of quality evaluation

Organized Legacy data

excel table Analysis,

Interpretation &

Organization Ground water quality

point data layer

Legacy GWQ data

Fresh GWQ data Lat-

Long data

Satellite Data

Settlement data Inte

rmed

iate

o

utp

uts

Interpolation

using statistical

method

Element-wise ground


Ground water

quality point data

layer

Inte

rme

dia

te

ou

tpu

ts

Integrated ground water

quality layers

Element-wise

ground water

quality layers

Grouping &

Intersection of

layers In

term

ed

iate

o

utp

uts


map (corresponding to

1:50,000 scale toposheet)

Integrated GWQ

layers, Base map

layers

Fin

al

ou

tpu

t

Validation, Map

composition &

Clipping

Quality checking - 2

Quality checking - 3

Internal Team

Internal Team

External Team

External Team

Quality checking - 1 Internal Team External Team

Ground water quality map (shallow depth zone) corresponding to 1:50,000 scale toposheet

Thank You!

Download - Groundwater Quality mapping

Top Related