(SEM V) THEORY EXAMINATION 2017-18 ENVIROMENTAL ENGINEERING 1

Environmental Engineering–I (NCE-503 / ECE-503)

Section-Wise Important Questions & Study Notes

SECTION–A

(Attempt all questions | 2 × 10 = 20)
Tip: Write definitions in 2–3 lines, no diagrams needed.

Design Period
The design period is the future time span for which a water supply or sewerage system is planned to meet expected demand.

Domestic Water Demand
It is the quantity of water required for household uses such as drinking, cooking, bathing, washing, and cleaning.

Pipe Materials
Pipe materials are substances used for manufacturing pipes—commonly cast iron, ductile iron, steel, PVC, RCC—selected based on pressure, durability, and cost.

Commonly Used Hand Pump
The reciprocating (piston) hand pump is commonly used due to simplicity and ease of maintenance.

Types of Pumps
Centrifugal pump, reciprocating pump, turbine pump, jet pump, submersible pump.

Small Bore Sewer System
A sewer system that carries only liquid waste after removing solids in interceptor tanks; suitable for low-cost sanitation.

Lapse Rate
The rate at which atmospheric temperature decreases with increase in altitude.

Acid Rain
Rainfall containing acids formed from SO₂ and NOx emissions, harmful to soil, water bodies, and structures.

Function of Sluice Gate
Used to control, regulate, or isolate the flow of water in pipelines.

Storm Regulator
A device in combined sewers to divert excess storm water during heavy rainfall.

SECTION–B

(Attempt any THREE | 10 × 3 = 30)
Tip: Use headings + small sketches where helpful.

1. Methods of Population Forecasting

Explain any four with suitability:

Arithmetic Increase Method (constant increase)

Geometric Increase Method (percentage growth)

Incremental Increase Method (trend-based)

Logistic Curve Method (saturation growth)
Mention where each method is suitable (small towns, fast-growing cities, mature cities).

2. Sewer Pipe Design vs Water Supply Pipe Design

Differentiate on:                Flow nature (gravity vs pressure)

Velocity criteria                 Materials

Design considerations      Then solve the DWF numerical using given population and LPCD.

3. Water Distribution Systems

Explain:                     Continuous system               Intermittent system
Compare advantages & disadvantages (pressure, quality, losses, equity).

4. Sewer Appurtenances

Explain with purpose:                  Manhole

Lamp hole                                  Inlet basin

5. Sewer Flow Numerical (Manning’s Equation)

Calculate velocity and discharge for a sewer running half-full using given diameter, slope, and Manning’s n.

6. Effects of Air Pollution

Explain sources, types of pollutants, health effects, environmental impacts, and control measures.

SECTION–C

(Attempt any ONE | 10 × 1 = 10)

3(a) Infiltration Galleries & Infiltration Wells

Explain:                                    Definition

Construction                           Working principle

Advantages                             Add neat sketches (important).

OR

3(b) Population Forecasting Numerical

Using census data (1971–2001), estimate population for 2015 & 2021 by:

Arithmetic increase                 Geometric increase

Incremental increase               Show steps clearly.