River Flooding Siege Tactic

A military engineering procedure for breaching fortified cities through hydraulic warfare.

Overview

When facing a well-fortified city that resists conventional assault, use water diversion to compromise defensive structures.

Steps

1. Survey the terrain: Identify nearby rivers or water sources that can be diverted
2. Plan diversion routes: Construct canals or channels (河沟) to direct water toward the target city
3. Execute diversion: Breach or redirect water flow toward city walls
4. Monitor effects: Wait for water pressure to compromise walls and foundations
5. Accept surrender: Once walls collapse, the defending ruler will typically surrender
6. Secure territory: Take control of the entire region

Prerequisites

• Target city must be situated in a location vulnerable to flooding
• Sufficient engineering resources and labor force
• Control of upstream water sources

Expected Outcomes

• City walls collapse under water pressure
• Minimal direct combat casualties
• Complete territorial acquisition

Historical Example

In 225 BCE, Wang Ben diverted river waters to flood Daliang (Wei's capital), causing the walls to collapse and forcing King of Wei to surrender.

Validation

• Verify that terrain survey confirmed the target city is vulnerable to flooding with accessible upstream water sources
• Confirm that diversion channels (河沟) are engineered to direct sufficient water pressure against walls and foundations
• Check that surrender terms and territorial control plans are prepared before initiating the water diversion