HYDROZONE Benefit Retention Tank

The measurement of the tank filling level by the EPM is the basis for modules utilising rainwater collected in the retention chamber. The EPM measurement is linked to the BUMERANG SMART monitoring and management system.

Based on data from the EPM measurement system and weather forecasts, an algorithm for controlling and using on-site retained water will be implemented. The system continuously analyses the condition of individual objects and automatically initiates appropriate system actions based on implemented algorithms. In the event of a forecasted precipitation exceeding the current retention capacity of the tanks or the performance of the normal water discharge system, a procedure to lower the level of the retention tank will be initiated. Additionally, the current status of monitored facilities is presented, and, in case of adverse events, appropriate alarms are generated.

The tank filling level measurement is performed using a standard hydrostatic probe (optionally, a radar probe can be used) mounted directly in the retention tank. The level measurement using the probe is based on the relationship between the liquid column height and the generated hydrostatic pressure. The measurement system includes a set of mounting elements necessary for installing the probe in the retention chamber.

Due to the sewage network layout, drainage from the retention part of the tanks can be carried out:

• gravity-wise through a drainage pipe, or
• pressure-wise through a pump system with suitable operating parameters.

For tanks, where rainwater and snowmelt are utilised, it is essential to retain the medium in the retention part. From the user’s perspective, it is important for such a process to be automated.

Depending on the type of water discharge from the tank, the following systems can be used:

• EOG – gravity drainage control from the tank,
• EOP – pressure drainage control from the tank.

In the EOG system, automatically controlled gates are used depending on the diameter of the drainage. The hydraulic equipment is mounted directly in the tank’s retention chamber. Access to the gate from ground level is provided (facilitating operational and servicing activities).

In the EOP system, pumping systems are used. This system consists of submersible pumps mounted on a coupling base and hydraulic-mechanical equipment consisting of discharge pipes and fixtures (check valves, shut-off gates). The diameter of the discharge pipes is appropriately selected relative to the flow rate and pump operation scheme. The table below presents pressure drainage systems for specific hydraulic parameters. If the calculated parameters deviate from the data listed in the table, it is also possible to select a pumping station for other parameters and taking into account the user’s individual requirements.

Connections of fixtures to pipelines are made to enable their subsequent disassembly. Automatic control of pump operation and signalling of emergency states is ensured by the power-supplying and controlling device. To ensure proper operation of the pumping system, parameters such as water level, flow, pressure, voltage, current intensity, and operating time are monitored and signal the operating state of the pumping system.

Based on data from the EPM measurement system (tank filling level measurement) and weather forecasts, an algorithm for controlling tank drainage will be implemented. In the event of forecasted precipitation exceeding the current retention capacity of the tanks or the performance of the normal water discharge system, a procedure to lower the level of the retention tank will be initiated (opening the automatic closure in the case of the EOG system or activating pumps in the case of the EOP system). Efficient tank drainage is possible thanks to the EPM tank measurement system and the BUMERANG SMART monitoring and management system.

To refresh (aerate) the medium stored in the retention chamber for an extended period, aerating nozzles can be used. By producing a strong stream of liquid and air bubbles, aerating nozzles create particularly favourable conditions for oxygen transfer and counteract sedimentation of solids.

The aerating nozzle consists of a feeding pump, a main column with control and monitoring devices, and an outlet pipe.

The base of the aerating nozzle is attached to the bottom with the nozzle, and the pump is lowered into the working position along guides. A hatch is designed above the pump. A moisture sensor is built into the pump motor chamber, together with thermal sensors on each phase of the motor winding, the so-called 1-2 safety circuit output in the pump cable.

To ensure durability and low maintenance costs, the system (except for the feeding pump and fixtures) must be entirely made of corrosion-resistant materials – stainless steel and composite elements.

The number of aerating nozzles is designed and selected in consideration of the dimensions of the retention chamber.

EPW1 system

The suction pipe, located in the tank, is made of stainless steel with a nominal diameter of 100 mm. The lower end of each suction pipe is equipped with a suction basket. The basket has a check valve and a valve release ear, allowing water to be drained from the suction pipe after water intake is completed. The upper part of the suction pipe is led above the ground and terminated with a horizontal section of a pipe equipped with a nozzle and a nozzle cover.

This solution allows water intake for sludge trucks.

EPW2 system

The water collection point is a convenient and accessible solution for residents. It allows for water retrieval from the concrete retention tank. The water collection point is located on the surface of the terrain, on prepared ground. The hydraulic equipment is concealed within a column, positively impacting the visual aspect. The operation principle of the water collection point is straightforward. To activate the point, simply press the button located on its body. This triggers water flow through the tap located below.

Water loss control from the tank can be managed through the Bumerang Smart monitoring system. This system provides operators with the ability for remote and real-time monitoring of water levels in the tank, as well as the ability to temporarily disable water retrieval if necessary.

The water collection point is available during the spring-autumn period (from April to May). During the winter period, water is drained from the point and taken out of operation.

The water collection point has a height of 1 metre. Material composition: stainless steel 1.4301.

Due to the variability of rainwater parameters and the degree and type of pollutants depending on the catchment, from which rainwater is collected, it is possible to use a rainwater treatment system. This is particularly important for the EPW2 system, where users have close contact with the medium.
Treated water is not suitable for drinking. Information regarding this is provided both in the device’s technical documentation and graphically directly at the water collection point.

The irrigation system is powered by a submersible pump located directly in the retention chamber. It consists of hydraulic-mechanical equipment, which includes a discharge pipe and shut-off-return fixtures (check valve, shut-off gate). On the discharge pipe, in a dedicated chamber, a filtration system and distributor are installed, enabling the supply to individual irrigation zones. Flow control and distribution to individual watering lines are achieved through the use of solenoid valves on each line. For automatic control of pump operation and the irrigation system, as well as fault signalling, a control-monitoring device is used.

Technical parameters of the irrigation system:

• Pump system located inside the retention tank,
• Chambers with filtration and control systems,
• Drip irrigation system.

The green area watering system allows for local and remote control of time and watering duration, separately for each zone. The number of zones is selected based on the size of the irrigated area, the type, and the method of the irrigation system.

The chamber with filtration and control systems is installed behind the retention tank.

Due to the size of the area and its diverse development, it is divided into zones, where the watering of each zone is activated independently.

Due to the variability of rainwater parameters and the degree and type of pollutants depending on the catchment, from which rainwater is collected, it is possible to use a rainwater treatment system.

Treated water is not suitable for drinking. Information regarding this is provided both in the device’s technical documentation and graphically directly at the water collection point.

Retained rainwater can be used for firefighting purposes. To ensure an adequate, undisturbed water level in the tank for extinguishing purposes, the tank is additionally supplied with water from the water supply network.

The tank is equipped with suction pipes made of stainless steel with a nominal diameter of 100 mm. The lower end of each suction pipe is equipped with a suction basket, protecting against the suction of incidental mechanical impurities that may be present in the water. The upper part of the suction pipe is led above the water intake level and terminated with a horizontal section of a pipe equipped with a nozzle and a cover of a 110 firefighting nozzle according to PN-M-51038 and PN-M-51024.

The number of suction pipes is determined in the PN-B-02857:2017-04 standard and depends on the tank’s capacity.

Retained rainwater can be used for toilet flushing purposes.

Rainwater collected from the building’s roof is gathered and directed to the retention tank. After preliminary purification, rainwater is stored in the retention tank with a quality maintenance system to avoid secondary contamination. The tank is equipped with a feeding pump supplying the refreshment and water treatment installation. From the retention tank, treated rainwater is directed to the EU-RECLEAN R rainwater treatment system, where it is purified and disinfected using devices, such as a filtration system and UV lamp. Treated water is stored in a hydrophore tank.

Treated water is not suitable for drinking. Information regarding this is provided both in the device’s technical documentation and graphically at the installation.

The water treatment installation is installed inside the building in an adapted room. This facilitates access to the installation.

Due to the possible lack of rainwater, there is an option for automatic switching to the water supply network.

The toilet flushing system is selected individually.

The above scheme presents a simplified block diagram of the installation.