Basement dewatering and drainage and water level monitoring system and construction method thereof

The invention discloses a basement dewatering and drainage and water level monitoring system and a construction method thereof. The system comprises a drainage well, a sump and a drainage waterway pipe network. The drainage waterway pipe network consists of a plurality of drainage pipelines; each drainage pipeline comprises a drainage main pipe, and each drainage main pipe is provided with at least two drainage main pipe outlets; an outlet of each main drainage pipe corresponds to one water collecting pit, each main drainage pipe is provided with a plurality of branch pipe connectors, each branch pipe connector corresponds to one water drainage well, and the branch pipe connectors are communicated with branch drainage pipes arranged in the water drainage wells; a water nozzle, a service valve, an adapter and a mud valve are sequentially connected in a water outlet pipe of the water collecting pit; an outlet of the main drainage pipe is communicated with a water outlet pipe of the sump through an adapter; the