The JSN-SR04T is a more rugged than the HC-SR04. The sensor will need to be tested outside.
You can easily view the results in the serial monitor when set at 9600 baud. 
VCC: Connect to the 5V pin on the Arduino R4 WiFi.

Trig: Connect to Digital Pin 9 on the Arduino R4 WiFi.

Echo: Connect to Digital Pin 10 on the Arduino R4 WiFi.

GND: Connect to the GND pin on the Arduino R4 WiFi.

This is a simple flood sensor prototype built from:
Arduino R4
Ultrasonic distance Sensor(HC-SR04)
Passive buzzer (KY-006)
Traffic Light LED Module
The distance is set at 50 cm from the sensor for the red light to turn on and the buzzer to activate.

Hardware Connections Checklist

• Ultrasonic Sensor (HC-SR04):

  • VCC to Arduino 5V

  • GND to Arduino GND

  • Trig to Arduino Digital Pin 4

  • Echo to Arduino Digital Pin 3

• LED Mini Traffic Light Module:

  • Red to Arduino Digital Pin 9

  • Yellow (you can leave this unconnected for this sketch)

  • Green to Arduino Digital Pin 7

  • GND to Arduino GND

• Passive Buzzer (KY-006):

  • S (Signal) to Arduino Digital Pin 8

  • + (VCC) to Arduino 3.3V

  • - (GND) to Arduino GND

Heavy rain, which started on August 10th, flooded part of the city of Kumamoto during the night. In the early hours of August 11th, the Iseri and Tsuboi rivers had overflowed in some parts of the city. The area shown on the map is the Hanazono area near Kami Kumamoto station.