noun
flood-control works; riparian works
Refers to civil engineering projects aimed at controlling rivers, preventing floods, and managing waterways. Often used in news and technical contexts.
この地域では治水工事が進められている。
Flood-control works are being carried out in this area.
治水工事のおかげで川の氾濫が減った。
Thanks to the riparian works, river flooding has decreased.
Compound of 治水 (flood control) and 工事 (construction work). The term is straightforward and modern, with no obscure historical derivation.