Pakistan, July 13 -- At least 50 people have died this week as Bangladesh wrestles with yet another monsoon. Around 35,000 have moved into shelters, while more than a million people remain stranded across seven districts. With the rain forecast to continue, the situation may take a turn for the worse.

Meanwhile, relief teams are taking food, water and medicine by boat to communities cut off by damaged roads. Bangladesh is rightly credited with building an effective cyclone-warning and evacuation system. However, the present emergency shows why that achievement cannot be treated as a complete model for every hazard.

Flash floods, landslides and urban waterlogging are shaped as much by drainage, settlement and enforcement as by the intens...