B.TECH FINAL YEAR PROJECT (MIDTERM)
Water Quality Index Development of
Jhajjar Distributary Region
WQI Modeling & Irrigation Suitability Assessment
STUDENT INVESTIGATORS
Department of Civil & Environmental Engineering
Varsh Ranga • Krishna Tyagi • Lakshya Phalaswal
Aditya Ojha • Sushil
PROJECT SUPERVISOR & GUIDE
Prof. Athar Hussain
Professor & Head, Department of Environmental Engineering
Introduction: River Water and Groundwater
Surface Water vs. Groundwater Dynamics
RIVER / SURFACE WATER
- Fed by rainfall, runoff, canals and distributaries
- Exposed to sewage, industrial waste and agricultural runoff
- Quality changes with season and flow variations
- Jhajjar Distributary: ~25 km canal from Bhalaut to Dhaur
- Receives domestic & agricultural return flows
- High variability in TDS, EC and coliform counts
- Seasonal dilution during monsoon, concentration in summer
- Critical source for downstream irrigation & drinking supply
GROUNDWATER
- Stored in alluvial aquifers of Indo-Gangetic plain
- Accessed via tube wells, hand pumps & bore wells
- Natural contaminants: Fluoride, Arsenic, Iron, Nitrate
- Human-induced pollution: Pesticides, fertilizers, leachate
- Slow recharge rate → pollutants persist for decades
- Jhajjar district: Groundwater is primary drinking source
- Declining water table due to over-extraction
A Water Quality Index (WQI) combines many parameters into a single score to judge water for drinking and irrigation.
PHYSICOCHEMICAL WATER QUALITY PARAMETERS (12 PARAMETERS)
Analyte Breakdown, Geochemical Origins & Environmental Significance
| Analyte / Parameter (Symbol) | Hydrochemical Significance & Toxicological Risks |
|---|---|
| pH (Acidity/Basicity) | Controls chemical speciation, heavy metal solubility, corrosivity, and palatability (Standard: 6.5–8.5). |
| TDS (Total Dissolved Solids) | Bulk indicator of mineral dissolution and salinity hazard; causes osmotic stress and gastrointestinal irritation. |
| Calcium (Ca²⁺) | Leached from calcite and dolomite; primary contributor to total hardness and household/boiler scaling. |
| Magnesium (Mg²⁺) | Hardness contributor from ferromagnesian minerals; exerts laxative purgative effects at elevated levels. |
| Sodium (Na⁺) | Silicate weathering and saline intrusions; critical driver of soil alkalization, dispersion, and sodicity hazard. |
| Potassium (K⁺) | Derived from orthoclase feldspar and NPK agricultural fertilizers; vital micronutrient with low baseline levels. |
| Total Alkalinity (TA) | Buffering capacity against acidification driven by HCO₃⁻/CO₃²⁻ from carbonate rock weathering. |
| Chloride (Cl⁻) | Conservative chemical tracer; elevated levels indicate municipal sewage, septic discharge, or saline backwater. |
| Sulphate (SO₄²⁻) | Gypsum dissolution and industrial runoff; causes bitter taste and cathartic laxative distress at >250 mg/L. |
| Nitrate (NO₃⁻) | Percolation of nitrogenous fertilizers and sewage; poses severe infant Methemoglobinemia ("Blue Baby Syndrome") risk. |
| Fluoride (F⁻) | Geogenic leaching from fluorite/apatite; levels > 1.5 mg/L cause irreversible dental and crippling skeletal fluorosis. |
| Total Hardness (TH) | Sum of divalent Ca²⁺ and Mg²⁺ ions; hinders soap lathering and shortens domestic/industrial piping lifespan. |
ANALYTICAL INSTRUMENTATION & TESTING PROTOCOLS
Standardized Experimental Assays, Instrumentation & Testing Procedures
| Parameter / Analyte | Analytical Method / Instrument | Experimental Protocol & Procedure Details |
|---|---|---|
| pH (Potential of Hydrogen) | Electrometric Method Digital pH Meter |
Measured electrometrically using a calibrated pH meter. Measures electrical potential due to H⁺ ions in solution. The measuring electrode system utilizes a standard glass electrode and calomel reference electrode calibrated with NIST standard buffer solutions (pH 4.01, 7.00, 9.20). |
| Total Alkalinity (TA) | Titrimetric Assay Acid Neutralization |
Standard wet-chemistry volumetric titration against 0.02 N H₂SO₄ using phenolphthalein and methyl orange indicators to determine total carbonate (CO₃²⁻), bicarbonate (HCO₃⁻), and hydroxide (OH⁻) buffering capacity. |
| Total Hardness (TH) | Complexometric Titration EDTA Method |
Complexometric titration using standard 0.01 M EDTA solution with Eriochrome Black T (EBT) indicator buffered at pH 10.0 (NH₄Cl-NH₄OH buffer) for total hardness (Ca²⁺ + Mg²⁺), with sharp wine-red to blue end-point. |
| Chloride (Cl⁻) | Argentometric Titration Mohr's Method |
Titrimetric assay using standardized 0.0141 N Silver Nitrate (AgNO₃) in presence of Potassium Chromate (K₂CrO₄) indicator until a distinct reddish-brown silver chromate (Ag₂CrO₄) precipitate forms. |
| Fluoride (F⁻) | Spectrophotometry SPADNS Colorimetry |
Colorimetric reaction using SPADNS reagent (Sodium 2-(parasulfophenylazo)-1,8-dihydroxy-3,6-naphthalenedisulfonate) and Zirconyl acid; bleaching of the red lake is measured spectrophotometrically at λ = 570 nm. |
| Calcium (Ca²⁺), Magnesium (Mg²⁺), Sodium (Na⁺), Potassium (K⁺) | AAS Atomic Absorption Spectrophotometry |
Measured by Atomic Absorption Spectrophotometry (AAS). Quantitative determination of major cations using element-specific hollow cathode lamps and air-acetylene flame atomization against matrix-matched multi-element standard calibration curves. |
| Sulphate (SO₄²⁻) | Turbidimetric Method UV-Vis Spectrophotometer |
Precipitation with Barium Chloride (BaCl₂) crystals in conditioning reagent medium to form uniform BaSO₄ colloidal suspension; turbidity absorbance is measured spectrophotometrically at λ = 420 nm. |
| Nitrate (NO₃⁻) | UV Spectrophotometry Dual-Wavelength Screening |
Direct UV spectrophotometric screening at λ = 220 nm with baseline organic matter absorption correction measured at λ = 275 nm using optical quartz cuvettes. |
| TDS (Total Dissolved Solids) | Gravimetric Method Whatman Filtration & Ignition |
Measured by filtration of water sample through Whatman filter paper (No. 42 / 0.45 µm) and subsequent drying/ignition of filtrate in a silica crucible heated at 550–650 °C to determine non-volatile dissolved mineral residue. |
REGULATORY STANDARDS & PARAMETER UNIT WEIGHT ASSIGNMENT
WHO & IS 10500 Regulatory Standards & Unit Weight Penalties
| Parameter (mg/L) | WHO Limit | IS 10500 | Unit Weight (Wn) | Rel. Weight |
|---|---|---|---|---|
| Fluoride (F⁻) | 1.5 | 1.0–1.5 | 0.620 | 62.0% (Highest) |
| pH (unitless) | 8.5 | 6.5–8.5 | 0.109 | 10.9% |
| Potassium (K⁺) | 12 | — | 0.078 | 7.8% |
| Total Hardness (TH) | 500 | 200–600 | 0.019 | 1.9% |
| Magnesium (Mg²⁺) | 50 | 30–100 | 0.019 | 1.9% |
| Nitrate (NO₃⁻) | 50 | 45 | 0.019 | 1.9% |
| Calcium (Ca²⁺) | 200 | 75–200 | 0.005 | 0.5% |
| Sodium (Na⁺) | 200 | — | 0.005 | 0.5% |
| Sulphate (SO₄²⁻) | 250 | 200–400 | 0.004 | 0.4% |
| Chloride (Cl⁻) | 250 | 250–1000 | 0.004 | 0.4% |
| Total Alkalinity (TA) | 500 | 200–600 | 0.002 | 0.2% |
| TDS | 1000 | 500–2000 | 0.001 | 0.1% |
CRITICAL INSIGHT
72.9% Weight Dominance
Fluoride (Wn = 0.620) and pH (Wn = 0.109) together command almost three-quarters of the entire WQI penalty function.
TOXICITY THRESHOLDBecause Wn is inversely proportional to permissible standard Sn, any marginal exceedance of Fluoride above 1.5 mg/L triggers severe index inflation, categorizing water as "Very Poor" or "Unfit" for human consumption.
FIELD STUDY AREA: JHAJJAR DISTRIBUTARY SYSTEM
Western Yamuna Canal Command | Hydrological Corridor & Agricultural Lifeline
Jhajjar Distributary Field Study Area (WYC Reach)
Bhalaut Regulator (Head) → Dhaur Outfall (Tail) | Reach ~25–35 km | Command Area: ~18,500 ha
HYDROLOGICAL DOSSIER
Regional Agronomic & Hydrogeological Role
- Canal Alignment & Reach: Originates from Bhalaut Regulator on the Western Yamuna Canal (WYC) system; courses ~25–35 km southwards through Jhajjar district, terminating near Dhaur outfall.
- Command Area Served: Culturable Command Area (CCA) of ~18,500 hectares (ha) of fertile agricultural land across multiple agrarian villages in Jhajjar district.
- Agricultural Lifeline: Provides essential gravity-fed irrigation for ~18,500 ha producing Wheat, Mustard, Pearl Millet (Bajra), and Paddy.
- Aquifer Recharge Corridor: Acts as the primary freshwater artificial infiltration buffer that continuously replenishes shallow aquifers against regional brackish/saline groundwater intrusion.
- Environmental Vulnerabilities: Marked tail-end conveyance losses, agricultural runoff (pesticides, nitrates), livestock washing, bank erosion, and localized untreated graywater dumping.
MATHEMATICAL FORMULATION: DRINKING (WQI) & IRRIGATION (IWQI)
Weighted Arithmetic Formulation & Agronomic Soil-Water Alkalinity Indices
DRINKING WQI FORMULATION
Weighted Arithmetic Index Method
WQI combines many parameters into a single score that tells how suitable water is for drinking by using the weighted arithmetic index method.
Step 1: Unit Weight (Wn)
Wn = K / Sn | K = 1 / Σ(1/Sn)
• Wn = Unit weight of n-th parameter
• Sn = Standard permissible limit
• K = Proportionality constant
Wn = K / Sn | K = 1 / Σ(1/Sn)
• Wn = Unit weight of n-th parameter
• Sn = Standard permissible limit
• K = Proportionality constant
Step 2: Quality Rating Sub-Index (Qn)
Qn = 100 × [(Vn - Vi) / (Sn - Vi)]
• Vn = Measured experimental value
• Vi = Ideal pure water value (Vi = 0 for chemical ions; Vi = 7.0 for neutral pH)
• Sn = Standard permissible limit
Qn = 100 × [(Vn - Vi) / (Sn - Vi)]
• Vn = Measured experimental value
• Vi = Ideal pure water value (Vi = 0 for chemical ions; Vi = 7.0 for neutral pH)
• Sn = Standard permissible limit
Step 3: Composite Drinking Index (WQI)
WQI = Σ(Qn × Wn) / ΣWn
• Composite weighted quality score (where ΣWn = 1.0)
WQI = Σ(Qn × Wn) / ΣWn
• Composite weighted quality score (where ΣWn = 1.0)
IRRIGATION IWQI SUITE
Soil Permeability & Sodicity Indices
Irrigation suitability depends on salinity and sodium hazard, which affect soil structure, permeability and crop growth. It is assessed with four indices, classified separately, using ions in meq/L.
Sodium Adsorption Ratio (SAR):
SAR = Na⁺ / √[(Ca²⁺ + Mg²⁺) / 2]
Measures sodium alkali hazard & soil dispersion
SAR = Na⁺ / √[(Ca²⁺ + Mg²⁺) / 2]
Measures sodium alkali hazard & soil dispersion
Sodium Percentage (%Na):
%Na = [(Na⁺ + K⁺) / (Ca²⁺ + Mg²⁺ + Na⁺ + K⁺)] × 100
Evaluates sodium concentration vs total cations
%Na = [(Na⁺ + K⁺) / (Ca²⁺ + Mg²⁺ + Na⁺ + K⁺)] × 100
Evaluates sodium concentration vs total cations
Magnesium Hazard (MH) & Kelley's Ratio (KR):
MH = [Mg²⁺ / (Ca²⁺ + Mg²⁺)] × 100
KR = Na⁺ / (Ca²⁺ + Mg²⁺)
MH assesses magnesium toxicity; KR assesses excess sodium
MH = [Mg²⁺ / (Ca²⁺ + Mg²⁺)] × 100
KR = Na⁺ / (Ca²⁺ + Mg²⁺)
MH assesses magnesium toxicity; KR assesses excess sodium
(Note: All ionic values strictly in milliequivalents per liter: meq/L)
WATER CLASSIFICATION MATRIX & SUITABILITY SCALES
Potability Tiers (Drinking WQI) vs. Agronomic Thresholds (Irrigation IWQI)
DRINKING WQI MATRIX
Potability Suitability Tiers
| WQI Range | Classification | Suitability Action |
|---|---|---|
| 0 – 25 | Excellent | Pristine; direct potable consumption. |
| 26 – 50 | Good | Standard domestic use; basic filtration. |
| 51 – 75 | Moderately Poor | Treatment required; coagulation/filtration. |
| 76 – 100 | Very Poor | Unsuitable for direct use; advanced RO needed. |
| > 100 | Unfit | Severe health hazard; prohibited from drinking. |
IRRIGATION SUITABILITY
Agronomic Thresholds
| Irrigation Index | Range | Agronomic Class |
|---|---|---|
| Sodium % (%Na) | < 60% > 60% |
Suitable Unfit (Deflocculation) |
| SAR (Richards) | < 10 10–18 18–26 > 26 |
Excellent Good Doubtful Unfit |
| MH (Szabolcs) | < 50 > 50 |
Safe Unfit (Soil Alkalinity) |
| Kelley's Ratio | < 1.0 > 1.0 |
Suitable Unfit (Na Hazard) |
Our Progress
Current Milestone Status & Next Experimental Phases
COMPLETED
Milestones Achieved
- Studied the water quality parameters and how each one is tested
- Examined various areas and selected the Jhajjar Distributary
IN PROGRESS
Current Activity
- Finding sampling locations and collecting samples for testing
NEXT
Upcoming Roadmap
- Test the samples in the laboratory
- Calculate WQI and IWQI and assess the water quality of the distributary
THANK YOU & KEY REFERENCES
Academic Citations, Methodological Benchmarks & Q&A Discussion
Q&A SESSION & DISCUSSION
Thank You!
We sincerely appreciate your valuable time, feedback, and guidance.
Project: Water Quality Index Development for Jhajjar Distributary
Domain: Environmental Engineering & Water Resources
Faculty Guide: Prof. Athar Hussain
Evaluation: Midterm Milestone Review & Roadmap
Domain: Environmental Engineering & Water Resources
Faculty Guide: Prof. Athar Hussain
Evaluation: Midterm Milestone Review & Roadmap
Open Floor for Discussion:
- Distributary reach station selection & sampling spatial distribution
- QA/QC verification with Charge Balance Error (CBE < 5%)
- Comparative sensitivity of Drinking WQI vs. Irrigation IWQI
ACADEMIC REFERENCES & BENCHMARKS
PRIMARY METHODOLOGICAL BENCHMARK
Nature Portfolio (2025)
"Integrated groundwater quality assessment using geochemical modelling and machine learning approach in Northern India"
Islam, R., Sinha, A., Hussain, A., Deshmukh, K., Usama, M., Ahmed, S., Deolia, R. K., Kumar, J., & Ali, S. (2025).
Scientific Reports, 15:37675. DOI:
Scientific Reports, 15:37675. DOI:
10.1038/s41598-025-21592-4
✦ Methodological benchmark for 12 physicochemical parameter protocols, unit weight assignments, and WQI/IWQI index formulation.
Standard Specifications & Testing Manuals:
- IS 10500:2012 — Bureau of Indian Standards: Indian Standard Drinking Water — Specification (Second Revision), New Delhi.
- WHO (2017) — World Health Organization: Guidelines for Drinking-water Quality (4th Edition), Geneva.
- APHA (2017) — Standard Methods for the Examination of Water and Wastewater (23rd Edition), American Public Health Association, Washington, D.C.