Urban Infrastructure Monitoring

Stormwater-Sewage Separation Online Monitoring System Solution

Q: Does the velocity coefficient of a Doppler radar flowmeter need field calibration? How is a gauging-based calibration performed?

Yes. Radar measures surface velocity at a point; converting it to cross-sectional mean velocity requires a coefficient K, theoretically in the 0.85–0.95 range. HZ-KSLF ships with the COSP model pre-loaded with a dynamic K relationship for standard sections (rectangular/trapezoidal), so regular lined canals can go straight into service. Natural rivers, compound sections and channels with unusual roughness, however, must be field-calibrated before commissioning — otherwise systematic error can exceed 10%. Standard calibration procedure: Pick a stable mid-flow period and gauge the section with a current meter (rotor or acoustic, multi-vertical multi-point method per GB 50179), recording HZ-KSLF surface velocity and level simultaneously. Cover at least low, mid and high stages with three or more gaugings each. Divide the measured mean velocity by the radar surface velocity and regress the K-value curve for the section (how K varies with stage). Write the section geometry (bed width, side slopes, roughness) and the K curve into the COSP model with the configuration software, or push it remotely through an EC32/EC60 series RTU. Run one or two verification gaugings afterwards; flow deviation should converge within ±5%. Key metering stations targeting ±2–3% need denser calibration. Recalibration cycle: quarterly during the first hydrological year, then once before each flood season once K proves stable. Re-calibrate immediately whenever the section scours or silts, lining is damaged, or new structures are built upstream or downstream. Gauging records can be exported over the RTU's Modbus/4G channel for hydrological review and archiving. For more details, visit our product pages or contact our technical team.

Q: Can a Doppler radar flowmeter be installed under a bridge or inside a box culvert? What space and clearance limits apply?

Yes, but the two scenarios impose very different constraints and must be handled separately. Bridge-mounted measurement is the classic non-contact installation. The HZ-KSLF sensor is fixed to the parapet or a cantilever bracket with the beam aimed vertically at the water surface; the clearance from sensor to water must stay within 0.5–15 m. Three things to watch: first, the beam footprint has to land on the straight approach reach upstream of the bridge, clear of pier wakes — the zone 3–5 pier-widths downstream of a pier is turbulently disturbed and unusable as a measuring point. Second, on steel bridges with noticeable deck vibration, the bracket needs damping, otherwise wind-induced shake couples into the velocity signal. Third, power and telemetry: bridges rarely have mains supply, so the standard kit is a solar panel plus battery, with 4G backhaul and an EC32 series RTU doing acquisition and forwarding. Box culverts and closed conduits turn on radar line-of-sight. Inside there is no GPS, no light and often less than 1 m of headroom. The HZ-KSLF still works at low clearance (minimum mounting height about 0.5 m), provided you confirm: the conduit runs partly full — if it flows full, switch to an LGF-PA66 magnetic flow meter for pressurised metering; there is a mounting platform and access hatch in the crown; and the sensor sits on a straight reach at least two conduit-diameters inside the portal where the velocity profile is settled. 4G signal is weak inside culverts, so run an external antenna to the portal, or choose an EC60 series RTU with NB-IoT for extra link budget. For both scenarios we recommend one manual gauging at commissioning to calibrate the section coefficient into the COSP model before the site goes live. For more details, visit our product pages or contact our technical team.

Stormwater and sewage network separation monitoring with overflow early warning and real-time water quality alarms

Overview

Summary

Stormwater and sewage network separation monitoring with overflow early warning and real-time water quality alarms

Key Advantages

Real-time stormwater/sewage network level and flow monitoring

Automatic identification of dry-weather sewage discharge and wet-weather overflow

Multi-parameter online water quality monitoring (COD/ammonia/pH)

GIS map visualization and pollution source tracing analysis

Storm warning linkage and emergency dispatch

Quantitative assessment of separation retrofit effectiveness

Challenges

Widespread stormwater-sewage cross-connections causing dry-weather sewage discharge and wet-weather overflow
Manual inspection cannot timely detect cross-connections with low efficiency and high cost
Unknown network status during storms with delayed overflow pollution warnings
Lack of quantitative assessment tools for separation retrofit effectiveness
Limited water quality monitoring points making pollution source tracing difficult

Results

200 monitoring points deployed in city center, 58 cross-connections identified and corrected in 3 months
Water quality compliance rate improved from 65% to 92% after monitoring system launch
30-minute advance warning prevented 3 major pollution incidents during storms
Precise location of 5 illegal discharge enterprises through water quality source tracing
Retrofit effectiveness assessment cycle reduced from 6 months to real-time

Solution Details

Policy Background for Stormwater-Sewage Separation Monitoring

Urban water body pollution control requires effective stormwater-sewage separation. Regulatory requirements increasingly mandate elimination of direct sewage discharge and implementation of separate drainage systems. Cross-connections between stormwater and sewage networks are a major cause of urban water pollution. The Stormwater-Sewage Separation Online Monitoring System Solution addresses these critical environmental challenges by providing continuous, data-driven oversight of drainage infrastructure.

Technical Highlights: Multi-dimensional Monitoring and Intelligent Recognition

Ecolor's stormwater-sewage separation monitoring system uses three-dimensional "flow + level + water quality" monitoring for precise identification of cross-connections and overflow pollution. Dry-weather baseflow analysis establishes normal flow baselines; rainfall response models predict overflow risks; water quality fingerprinting enables rapid pollution source tracing. This intelligent recognition capability ensures accurate differentiation between legitimate stormwater discharge and illicit sewage connections.

Key Product Features of the Stormwater-Sewage Separation System

Real-time stormwater/sewage network level and flow monitoring
Automatic identification of dry-weather sewage discharge and wet-weather overflow
Multi-parameter online water quality monitoring (COD/ammonia/pH)
GIS map visualization and pollution source tracing analysis
Storm warning linkage and emergency dispatch
Quantitative assessment of separation retrofit effectiveness

System Architecture for Comprehensive Monitoring

The Stormwater-Sewage Separation Online Monitoring System Solution employs a robust four-layer architecture: sensing layer (Doppler flowmeters, level meters, water quality stations); transmission via Hero V9 RTU with 4G/NB-IoT; platform layer for data aggregation and GIS display; application layer with cross-connection identification, overflow warning, and source tracing. This layered design ensures reliable data collection and actionable insights for water management authorities.

Application Scenarios for the Monitoring Solution

The system is designed for diverse urban water management applications including urban water pollution control, separation retrofit effectiveness assessment, drainage user supervision, and storm flood early warning. Each scenario leverages the system's multi-dimensional monitoring capabilities to deliver precise, real-time information for decision-making.

Technical Parameters and Performance Metrics

Flow Monitoring

Doppler flowmeters

Level Monitoring

Level meters

Water Quality

COD/ammonia/pH

Communication

4G/NB-IoT via Hero V9 RTU

Data Visualization

GIS map display

Source Tracing

Water quality fingerprinting

Approach

How we implement intelligence into your infrastructure step by step.

Network Survey & Site Planning

Survey stormwater/sewage network distribution, outfall locations, and flood-prone areas; plan monitoring point layout prioritizing key rivers and historical overflow points.

Monitoring Equipment Deployment

Install Ecolor Doppler radar flowmeters, ultrasonic level meters, and water quality stations at key nodes; deploy Hero V9 RTU for data collection and 4G transmission.

Platform Setup & Model Building

Build monitoring platform, import GIS and meteorological data, establish dry-weather baseflow and storm overflow prediction models.

Trial Run & Problem Investigation

Analyze monitoring data during trial period to identify suspected cross-connections and illegal discharges, guide field investigation and remediation.

Long-term O&M & Effectiveness Assessment

Continuous monitoring of separation retrofit effectiveness with periodic reports on water quality compliance, overflow frequency, and remediation progress.