I. Project Overview

This project involves the smart retrofit of groundwater monitoring wells in the landscape areas of an urban park. The park features multiple landscape groundwater wells (such as the wells embedded in the lawn shown in the figure), which are used for landscape irrigation and dynamic monitoring of groundwater resources. Existing Monitoring Method: Water levels were measured manually at regular intervals by lowering a person into the wells with a tape measure. This method resulted in data lag and high labor costs, and it was impossible to monitor sudden changes in water levels during the rainy season or dry season in real time. There is an urgent need for automated water level monitoring equipment to enable round-the-clock online data collection and integration with the park’s smart water management platform.

The on-site monitoring wells consist of pre-buried PVC shafts located in an open lawn environment. They are exposed to year-round sun and rain, with significant day-night temperature fluctuations. The water inside the wells contains trace amounts of silt, placing stringent demands on the sensors’ waterproofing, weather resistance, and measurement stability.

II. Project Challenges

1. Low Efficiency of Manual Inspections: Daily on-site water level measurements by operations and maintenance staff are time-consuming due to the need to inspect dozens of monitoring wells, and sudden water level surges during the flood season cannot be warned in a timely manner;

2. Insufficient Measurement Accuracy: Manual tape measure readings have an error margin of ±1 cm to 3 cm, which fails to meet the requirements for detailed water resource statistics;

3. Environmental Adaptation Challenges: Outdoor, open-air installation—exposed to rain, humidity, and diurnal temperature fluctuations—often causes standard submersible level sensors to drift or malfunction frequently;

4. Inability to Upload Data Remotely: Due to the lack of digital signals, water level data cannot be integrated into the park’s central control system, making it difficult to coordinate the start and stop of landscape water pumps.

III. Solution: Adoption of Miran Magnetostrictive Level (Displacement) Sensors

1. Product Selection

The Miran MTL series probe-type magnetostrictive level sensor was adopted. Based on the principle of non-contact magnetostrictive measurement, it features a corrosion-resistant stainless steel probe paired with a matching corrosion-resistant float and outputs an RS485 digital signal, making it suitable for long-term operation in outdoor groundwater wells.

2. Installation Plan (Refer to the actual photos)

. Mount the sensor vertically at the center of the PVC well shaft. Secure the sensor body in place with three threaded rods to prevent displacement caused by water turbulence within the well;

. The float assembly is mounted on the stainless steel probe rod and rises and falls in sync with the water level, accurately measuring the liquid level via magnetic coupling;

. Power and communication signal cables are routed out of the well shaft and connected to the on-site data acquisition terminal; data is then uploaded to the park’s smart water management platform via an IoT module;

. The sensor is equipped with a white PVC protective sleeve to shield it from lawn mud, water, and fallen leaves, thereby enhancing its outdoor protection rating.

IV. Core Product Advantages

1. Ultra-high measurement accuracy: Full-range error ≤ 0.05% FS, with millimeter-level water level measurement. Compared to manual tape measure readings, data stability is improved, and subtle fluctuations in the groundwater level are accurately captured;

2. All-Weather Outdoor Durability: IP68 fully sealed stainless steel housing that withstands humidity, high and low temperatures, and is suitable for rain and snow on open lawns in southern regions. It exhibits no temperature drift or zero-point drift; non-contact measurement eliminates mechanical wear, ensuring a service life of 15+ years;

3. Convenient Digital Networking: Standard RS485 Modbus-RTU protocol enables direct integration with PLCs and IoT gateways. Water level data is automatically uploaded to the cloud, where the system automatically generates daily and monthly water level reports. Automatic pop-up alerts are triggered for water shortages during dry seasons and overflow during flood seasons;

4. Drastically Reduced O&M Costs: After retrofitting, manual daily inspections are eliminated, requiring only quarterly routine visual inspections, thereby reducing annual labor costs per well.

V. Project Outcomes

1. Smart Management: The park’s operations and maintenance team can remotely monitor water levels in all wells in real time. Landscape irrigation pumps are automatically activated or deactivated based on groundwater levels, enabling on-demand water use for landscaping and reducing annual landscape irrigation water consumption;

2. Water Resource Records: Continuous collection of annual groundwater level data creates a dynamic groundwater database for the park, providing authoritative data support for soil and water conservation and water resource management;

3. Severe Weather Alerts: During heavy rains in the flood season, real-time alerts are sent when water levels rise suddenly, allowing for early implementation of well drainage and protection measures to prevent well overflow from flooding the lawn.

VI. Industry Applications

This solution has been successfully replicated and applied in scenarios such as municipal landscape wells, groundwater monitoring wells in irrigation districts, and groundwater observation wells in wetland parks. Thanks to their weather resistance, high precision, and ease of networking, Miran magnetostrictive level sensors have become the preferred solution for precise outdoor hydrological monitoring.