Water Tower Monitoring: Remote Monitoring of Water Level, Pumps, and System Pressure

Challenges of Remote Monitoring a Water Tower

The water tower is the heart of a municipality’s or water district’s drinking water supply system. Its main function is to serve as a buffer reservoir and to maintain pressure in the distribution network through gravity. Any failure—such as a low water level, a pump failure, or a leak—has immediate repercussions for thousands of customers.

Historically, monitoring relied on daily patrols or landline telephones with level switches. Today, these systems are inadequate to meet regulatory requirements and subscribers’ service expectations. Modern remote monitoring offers:

• Continuous monitoring (24 hours a day, 7 days a week) of the water tower’s condition.
• Automatic alerts within 5 minutes in the event of an anomaly.
• Complete traceability for ARS audits and annual RPQS reports.
• The ability to intervene remotely to avoid on-site visits.

Key Parameters and Monitoring Thresholds

Monitoring a water tower involves several categories of measurements:

Tank Level

• Low alert threshold: 20% of usable capacity
• Critical low threshold: 10% (automatically activates the backup pump, if available)
• High threshold: 95% (pump shuts off, overflow alert)

Pressure Pumps

• On/off status and operating hours counter
• Current draw to detect cavitation or overload
• Motor temperature on large systems
• Number of starts per hour (anti-short-cycle protection)

Distribution Network

• Inlet pressure at the base of the tower
• Pressure at the lowest and highest points of the network (remote sensors)
• Hourly and daily flow rates for detecting nighttime leaks

Water Quality

• Residual chlorine, pH, turbidity at the reservoir outlet
• Compliance with Directive 98/83/EC and the decree of January 11, 2007

Technical Architecture

[Capteurs terrain]
  Hydrostatic Level Sensor
  PT100 pump motor
  Mains Pressure Sensor
  Analyseur chlore/pH
        |
        | RS-485 Modbus / 4-20 mA
        v
[Gateway IoT 4G DIN-rail]
  Acquisition multi-capteurs
  Local Alert Logic
  Data buffer (network outage)
        |
        | Encrypted VPN / 4G LTE
        v
[Plateforme cloud]
  Real-time dashboards
  Historiques et tendances
  Alertes SMS / email / push
  Rapports ARS automatiques
  Remote Control for Pumps and Valves

Use Case: Optimizing Pumping During Off-Peak Hours

One of the most important economic applications is off-peak pumping (HC). Monitoring makes it possible to:

1. Schedule the tank to fill during off-peak hours (reduced EDF rate).
2. Verify that the target level is reached by the end of off-peak hours.
3. Automatically detect if the pump has not started (alarm) or if the target level has not been reached (undersized pump or high leakage rate).
4. Calculate the pump’s electricity consumption and optimize the schedule.

For a 500 m³ water tower that is pumped twice a day, the systematic shift in peak demand can result in annual savings of €3,000 to €8,000 on the electricity bill.

Regulatory Compliance and ARS Reporting

The ARS (Regional Health Agency) requires that a health log be maintained, recording quality metrics, incidents, and interventions. The monitoring platform automatically generates:

• Time-stamped readings for chlorine, pH, and turbidity (in SISE-EAUX-compatible format).
• Non-compliance reports with time stamps for detection and resolution.
• Monthly reports on production volume, consumption, and network efficiency.

These documents are retained for 5 years and are available to ARS staff upon request.