Waterlogging mitigation — which set of measures directly helps to remove waterlogging from irrigated land?

Introduction / Context:
Waterlogging occurs when the water table rises into the root zone, degrading soil aeration and crop yields. Engineers address both the inflow (percolation into the aquifer) and the outflow (drainage or pumping) sides of the balance to restore a safe depth to the water table.

Given Data / Assumptions:

• Canal command with high seepage and inadequate drainage.
• Goal: lower water table and prevent salinization/alkalinization.
• Standard interventions: reduce percolation; improve outflow.

Concept / Approach:

Reduction of percolation (canal lining, watercourse lining, improved on-farm irrigation practices) decreases recharge to the groundwater. Simultaneously, increasing outflow (surface/subsurface drains, interceptor drains, pumping) removes excess groundwater. Acting on both terms best accelerates recovery from waterlogging.

Step-by-Step Solution:

Verification / Alternative check (if short method exists):

Water balance analysis before and after intervention should show reduced recharge and increased discharge, producing declining water table trends.

Why Other Options Are Wrong:

Only one-side action gives slow or partial relief; “neither” fails to address the cause; ignoring drainage overlooks the need for an exit path for groundwater.

Common Pitfalls (misconceptions, mistakes):

Assuming canal lining alone cures waterlogging; forgetting field drains and maintenance; neglecting conjunctive use of pumped groundwater.

Final Answer:

both (a) and (b)