All the rivers in the city territory were controlled under a "River Manager & District Manager" system, and a long-term controlling rate for watercourses of 100% was reached.

市域河流全面实行河长制和片长制管理，河道长效管理覆盖率达100%。

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The city would benefit from a siren system, said Larry Meyerhofer, emergency manager at the L.A. Emergency Management Department, but the cost is high.

FORBES: Earthquakes, Maybe. But Is Los Angeles Prepared For A Tsunami?