According to I.R.C. recommendations, a traffic volume study for rural roads should be conducted for 7 consecutive days during which seasonal period to capture representative conditions?

Introduction / Context:
Traffic volume studies underpin planning, capacity assessment, and pavement design for rural roads. The Indian Roads Congress (I.R.C.) emphasizes that counts be taken during representative periods so seasonal fluctuations—especially those driven by agricultural activity—are reflected in design traffic estimates.

Given Data / Assumptions:

• Facility type: rural roads with agricultural influence.
• Duration: 7 days of continuous counting.
• Objective: capture realistic traffic, accounting for seasonal variations.

Concept / Approach:
Rural traffic can vary significantly between harvest peaks and lean (off-harvest) periods. Conducting 7-day studies in both characteristic seasons yields a more robust estimate of AADT (annual average daily traffic) by bracketing the likely range and allowing seasonal factors to be derived for design traffic forecasts.

Step-by-Step Solution:
Plan two 7-day counts: one in harvesting and one in lean season.Compute average daily traffic for each and apply expansion factors.Combine with seasonal adjustment to estimate AADT and design traffic (e.g., commercial vehicle growth).

Verification / Alternative check:
Design manuals and typical state PWD practices mirror the I.R.C. guidance by discouraging counts only during unusual or festival periods; dual-season counting reduces bias from crop-cycle-induced peaks/lulls.

Why Other Options Are Wrong:

• Harvesting season only: overestimates average flow.
• Lean season only: underestimates average flow.
• None of these: incorrect; I.R.C. recommends considering seasonal variation explicitly.

Common Pitfalls:

• Conducting counts during holidays/fairs, which distort typical patterns.
• Using a single short count without seasonal adjustment factors.

Final Answer:
Both harvesting and lean season