Ecosol Off-Line GPT

The EcosolTM Off-line GPT suits conduits of almost any size and shape, off-line adjacent to creeks or in open channels as well as end-of-line. Its unique removable basket system enables captured pollutants to be easily removed without specialised cleaning equipment.

The EcosolTM GPT (Off-line stormwater treatment solution) is a non-blocking tangential filtration system. The EcosolTM Off-line GPT is designed to be installed off-line adjacent to creeks or open channels. Its unique removable basket system enables captured pollutants to be easily removed by either crane or vacuum method.

Many major drainage systems are designed with large open channels to allow significant flows to be conveyed away from urban catchments. In-line GPTs in such cases are often cost-prohibitive and almost always have an adverse impact on the drain’s hydraulic capacity. The EcosolTM Off-line GPT can be installed in such situations. The unit has the added benefit of being able to accommodate tidal and tail water conditions.

Similar to the In-Line EcosolTM GPT two unique systems have been designed, the Low Flow EcosolTM GPT for primary and secondary treatment of stormwater at low flow velocities and the High Flow Ecosol GPT for primary treatment of stormwater at high flow velocities.

Key Features

The High Flow EcosolTM Off-line GPT (formerly known as the RSF 4000 Solid Pollutant Filter) captures and retains more than 99% of pollutants larger than 2mm and the Low Flow EcosolTM Off-line GPT up to 80% of Total Suspended Solids, as well as 45% of Total Phosphorous and Total Nitrogen at its design TFR. Easily installed, the pre-cast, modular GPT’s can be installed adjacent to creeks or open channels where a custom designed and modelled diversion weir divert a percentage of the flows to the system for treatment.

Ecosol-Offline-GPT-01 off-line gpt Ecosol Off-Line GPT GPT Key Features Table R1 2015
1 Larger EcosolTM GPT’s may come in multiple parts.

Low Flow Ecosol GPT - Key Features

The Low Flow EcosolTM GPT has been designed and tested specifically to treat low flows to capture and retain fine suspended solids and hydrocarbons from stormwater. Its tangential screening along with its large detention chamber enables gravitational separation to occur at low flow velocities retaining fine particulate matter conveyed in stormwater providing essential primary and secondary treatment.

Ecosol Off-Line GPT hydraulics off-line gpt Ecosol Off-Line GPT Ecosol Off Line GPT 1Key Features

  • high capture efficiency of suspended solids at low flow velocities
  • designed high flow by-pass capacity
  • Independently tested and verified by the University of Adelaide
  • designed hydraulics provides minimal hydraulic headlosses
  • shallow depth below invert reduces water table problems
  • visually unobtrusive
  • easily cleaned using eductor truck or removable lift out baskets.
High Flow Ecosol GPT - Key Features

The range of High Flow EcosolTM GPT’s, are designed specifically to provide essential primary treatment of gross pollutants conveyed in stormwater at high velocities. Typically this system has been designed to capture and retain more than 99% of pollutants larger than 2mm.

Ecosol Off-Line GPT hydraulics off-line gpt Ecosol Off-Line GPT Ecosol Off Line GPT 3Key Features

  • minimal head/hydraulic loss
  • hydraulically-driven barrier reduces premature by-pass
  • designed hydraulics enables high treatable flow rates
  • shallow depth below invert reduces water table problems
  • visually unobtrusive
  • Independently tested and verified by the University of Adelaide
  • easily cleaned using eductor truck or removable lift out baskets
Hydraulics

The EcosolTM Off-line GPT is available in many different sizes and is capable of treating flows ranging from 70L/sec to 4,200L/sec.

In addition to high TFRs the unit has a significant holding capacity sized to suit typical pollutant loadings for the catchment type and size that it services.

The pre-cast, modular design shown opposite incorporates a constructed on-grade weir in the existing channel that diverts the designed TFR (normally a 1:3 month to 1:1 year ARI) through the unit, which is installed parallel to the flow.

All flows exceeding the designed TFR overtop the weir and by-pass the unit to the open channel or canal. The simple yet effective design enables the unit to be installed where conventional in-line GPTs are either cost-prohibitive or require too much space.

Applications - Cleaning and maintenance

The EcosolTM Off-line GPT systems are typically installed adjacent to large arterial drainage lines or on large industrial and commercial sites. It is also suitable for residential developments, airports, freeways, and most civil construction projects.

Cleaning and maintenance

The EcosolTM Off-line GPT’s simple design makes access for cleaning and maintenance easy using an eductor truck or crane truck for removable basket configurations. This eliminates any manual handling risks. The cleaning frequency depends on the catchment type and size but, as a guide, a unit serving a 17Ha residential catchment will need cleaning about twice annually.

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Off line GPT Maintenance off-line gpt Ecosol Off-Line GPT Off line GPT Ecosol 01 300x225

Ecosol Off-Line GPT cleaning and maintenance off-line gpt Ecosol Off-Line GPT Ecosol Off Line GPT 4

 

Key Dimensions

The table below shows the approximate dimensions and holding capacities for both, the low and high flow EcosolTM Offline GPT systems. Their capacity to retain large quantities of captured pollutants ensures that its specified capture efficiency is maintained between scheduled cleaning events.

 
 

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Ecosol-Offline-GPT-Titanium-Place-2Notes 1. The unit can be sized to suit almost any type of stormwater drain. 2. Unit dimensions can vary depending on the vehicle load requirements and the wall thickness.

Life Expectancy

The EcosolTM Off-line GPT is designed to meet the strictest engineering guidelines. The reinforced concrete has an expected life span of 50 years while the internal filtration components, comprised of 304 or 316-grade stainless steel, have a life expectancy of between 15 - 25 years.

Unit Design Basis

Design is based on Exposure Classifications A2 for external surfaces in contact with the ground and for installations in non-aggressive soils. Where the conditions are outside the design limits of the standard EcosolTM Off-line GPT, Ecosol must be notified in writing so that the product is designed specific to these site conditions. This includes instances where the unit is to be installed in aggressive soils, or below any permanent, or transient water table, or if the maximum depth of fill above the cover slab exceeds 3.0m for EcosolTM Off-line GPT 4300 - 4600 and 2.0m for the EcosolTM GPT 4750. Confirmation of the site ground and water conditions including cover is the responsibility of the client.

Unit Design Loading

The range of EcosolTM Off-line GPT’s are designed for Class B, D and up to Class G loadings suitable for underground installations in highways, airport and wharf applications.

 
 

Collection Efficiencies

Particle Size Distribution Collection Efficiency

In order to determine a meaningful characterisation of the products collection efficiency, an extensive verification phase (inclusive of field and laboratory testing) was undertaken by Avocet Consulting Pty Ltd, EcosolTM Pty Ltd and EngTest (The University of Adelaide). To best summarise the capture efficiency results of extensive product testing a regression of the data points using a sigmoidal regression curve was selected as it provided a conservative fit to the wide scatter of data collected. Refer to figures 1 and 2 for testing results. Table 1 summarises these results.

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Table 1- Typical PSD results.

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Figure 1 – Sigmoidal regression curve graph for Low Flow EcosolTM GPT laboratory testing.

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Figure 2 – Sigmoidal regression curve graph for High Flow EcosolTM GPT laboratory.

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Figure 3 - Field testing Particle size distribution data for six separate High Flow EcosolTM GPT installations.

Gross Pollutant Traps (GPTs), such as the EcosolTM Off-line GPT, are primarily designed to remove larger gross pollutants (>3mm) from stormwater at high treatable flow rates (TFR) and can play an integral role reducing pollution in heavilyurbanised catchments that discharge into our waterways.

In recent years modern Water Sensitive Urban Design (WSUD) objectives and principles now applied to most urban development’s require more onerous water quality objectives (WQOs) specifically targeting the removal of suspended solids, nitrogen, phosphorus and heavy metals. Subsequently EcosolTM designed and developed a low flow EcosolTM Off-line GPT specifically designed to target these constituents at low treatment velocities.

Since development of the EcosolTM GPT began in 1996, EcosolTM has commissioned a range of tests to confirm not only product performance but also to help with further research and development work.

In 1996, the University of South Australia, a National Australian Testing Authority (NATA) approved testing body, tested EcosolTM’s GPT to review pollutant capture efficiencies and also hydraulics. Further testing in 2000 and again 2012 by the University of Adelaide provided further measurements of the products capture efficiency at varying flow rates obtained from both field and laboratory testing data. The below tables summarise their findings for both the high and low flow EcosolTM GPT’s.

Low Flow EcosolTM Off-line GPT - Capture Efficiencies

Ecosol-Offline-GPT-07

 
 

Table 2 – Low Flow EcosolTM Off-line GPT performance summary.

High Flow EcosolTM Off-line GPT - Capture Efficiencies

Ecosol-Offline-GPT-08

 
 

Table 3 – High Flow EcosolTM Off-Line GPT performance summary.

The above capture efficiencies have been independently verified by laboratory and field tests confirming that the EcosolTM GPT plays an integral part in the treatment train necessary to achieve generally-accepted stormwater treatment objectives and WQOs.

Figures quoted are mean collection efficiency statistics based on available product testing data. It is important to note that the water quality CE values are indicative of potential field CEs given that product is designed primarily as a primary treatment solution providing physical screening and the removal of chemical constituents is largely dependent on the chemical composition of the particles and the bonding of these chemical constituents to the surface of particles. Further, finer and attached particle filtration performance of the product is also dependent on the body of pollutants forming a media already captured by the filter. Quoted CE values are intended as a general guide, please consult with your Ecosol representative for site specific product sizing and modelling.

 
 

Hydraulic Specification

Treatable Flow Rate
Gross Pollutant Traps (GPTs), such as the EcosolTM Off-line GPT, are primarily designed to remove larger gross pollutants (>3mm) from stormwater at high treatable flow rates (TFR) and can play an integral role reducing pollution in heavily urbanised catchments that discharge into our waterways.

In recent years modern Water Sensitive Urban Design (WSUD) objectives and principles now applied to most urban development’s require more onerous water quality objectives (WQOs) specifically targeting the removal of suspended solids, nitrogen, phosphorus and heavy metals. Subsequently Ecosol designed and developed a low flow GPT specifically designed to target these constituents at low treatment velocities.

Since development of the EcosolTM GPT began in 1996, EcosolTM has commissioned a range of tests to confirm not only product performance but also to help with further research and development work.

In 1996, the University of South Australia, an approved testing body, tested EcosolTM’s GPT to review pollutant capture efficiencies and also hydraulics. Further testing in 2000 and again 2012 by the University of Adelaide provided further measurements of the products capture efficiency at varying flow rates obtained from both field and laboratory testing data. The below tables summarise their findings for both the high and low flow EcosolTM GPT’s.

Low Flow EcosolTM Off-line GPT - Capture Efficiency and Treatable Flow Rates

The TFR is the minimum flow that a GPT must treat, without by-pass, to achieve the desired pollutant capture criteria for a particular development type and catchment area. It varies dependent on pipe size and gradient. Typically, the Low Flow EcosolTM Off-line GPT, is designed to treat flows between 1-in-3 month and 1-in-1 year Annual Rainfall Intensity (ARI) discharges, with greater flows by-passing the unit.

The Low Flow EcosolTM Off-line GPT, was designed specifically to achieve high pollutant removal rates at low inflow velocities thereby providing improved gravitational separation of particulates conveyed in stormwater. The table below summarises the Low Flow EcosolTM Off-line GPT, performance.

Ecosol-Offline-GPT-07

 
 

Below are the TFRs (shown as litres/second) for the most typical Ecosol Low Flow EcosolTM Off-line GPT’s, although the TFR can be altered to suit site-specifics. Please contact your EcosolTM representative for help in sizing a unit to cater for a particular TFR.

Ecosol-Offline-GPT-10

 
 

The above Low Flow EcosolTM Off-line GPT, treatable flow rate figures are a general guide only and may vary depending on site specific hydraulic including diversion weir heights, channel or drain capacity and gradient. Please consult with your local EcosolTM representative for accurate flow calculations specific to your site.

 
 

High Flow EcosolTM Off-lin GPT - Capture Efficiency and Treatable Flow Rates

The High Flow EcosolTM Off-Line GPT’s, are primarily designed to remove larger gross pollutants (>3mm) from stormwater at high treatable flow rates (TFR) and can play an integral role reducing pollution in heavily-urbanised catchments that discharge into our waterways.

The range of High Flow EcosolTM Off-Line GPT’s are designed to provide essential pre-treatment of stormwater at high velocity flows and is therefore an integral part of any treatment train. The table below summarises the High Flow EcosolTM Off-line GPT, performance.

Ecosol-Offline-GPT-11

 
 

Below are the TFRs (shown as litres/second) for the most typical High Flow EcosolTM Off-Line GPT’s, although the TFR can be altered to suit site-specifics. Please contact your EcosolTM representative for help in sizing a unit to cater for a particular TFR.

Ecosol-Offline-GPT-12

 
 

By-pass Capacity and Headloss

The range of EcosolTM Off-line GPT’s are hydraulically designed and modelled to suit site specific conditions. This includes the design of the diversion weir, diversion inlet and outlet configurations and GPT sizing.

Typically the EcosolTM Off-line GPT is designed to treat flows between 1-in-3 month and 1-in-1 year Annual Rainfall Intensity (ARI) discharges, with greater flows overtopping the diversion weir with designed hydraulic losses. Please contact your EcosolTM representative for help in sizing a unit specific to your site requirements.

 
 

Maintenance

As with all filtration systems, the EcosolTM Off-line GPT should be inspected and cleaned regularly. The cleaning frequency, and the cost, depends heavily on the catchment size and type, the unit’s proximity to a waste facility, and rainfall.

The cleaning frequency may vary with local catchment conditions but the below figures are based on typical gross pollutant loads expected for typical commercial, residential, and light industrial catchments and provide a broad guideline about the catchment size and the number of cleans required annually. Gross pollutants include vegetation as well as anthropogenic litter but exclude sediment. The figures give consideration to the volume of pollutants in the unit and to eductor truck holding capacities and cleaning costs for a fully-loaded truck. In some instances, it may be cheaper to clean a unit more frequently than undertaking, say, annual cleans where the volume requires more than one truck load.

One of the key advantages of the EcosolTM Off-line GPT is that it can be designed for cleaning by either vacuum (eductor truck) or removable basket (crane truck) method.

 
  Ecosol-Offline-GPT-H-Bush-SiteEcosol-Offline-GPT-013 Ecosol Off line GPT Maintenance





 

 

 
 

Catchment Size and Recommended Cleaning Frequency

The tables below provide a broad guideline about the catchment size and the number of cleans required annually.

Ecosol-Offline-GPT-15

 
 

Table 1 – Low Flow EcosolTM Off-Line GPT recommended maintenance program.

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Table 2 – High Flow EcosolTM Off-Line GPT recommended maintenance program.

Ecosol-Offline-GPT-01-H-Bush-Gas1 Cleaning frequency is based on typical gross pollutant loads anticipated for standard commercial, residential and light industrial catchments. Gross pollutants in this instance includes vegetation as well as anthropogenic litter, however excludes sediment. Cleaning frequencies may vary based on local catchment conditions and rainfall.

EcosolTM has a very competitive cleaning service. After each clean we provide a report detailing the volume and type of pollutants removed. We believe that it is in your best interests for EcosolTM staff to clean and maintain the unit, not only because we are specialists, but also because proper monitoring and maintenance enhances the unit life significantly. Should you use another company to clean the unit, or undertake this work yourself, we request that it be conducted according to EcosolTM’s specifications. Otherwise, you may invalidate your warranty, as damage caused by inappropriate cleaning procedures is not covered. The advantages of using Ecosol to clean and maintain your unit are that you get:

  • regular inspections of your unit and diversion structures
  • a comprehensive cleaning service with removal and disposal of all captured pollutants
  • a detailed report provided on completion of each clean
  • trained and experienced staff; and remedial work completed, if required.
 

 

 

Applications

The EcosolTM Off-line GPT in the applications shown below are designed to remove gross pollutants, coarse sediment and attached pollutants at high flows from major arterial drains. These images below are typical installations of the EcosolTM Off-line GPT.

To assist you with your next project EcosolTM provides a unique turnkey service including modelling, structural design, installation, commissioning and maintenance services to ensure your EcosolTM Off-line GPT is appropriately designed for the environment in which it is installed.

DSCN2135Ecosol-Off-Line-GPT-Titanium-Place-2Ecosol-Offline-GPT-Malay

 
     
     
     
     

Ecosol GPT Maintenance Guide
 

EcosolTM GPT - Maintenance guide


EcosolTM Off-Line GPT - Maintenance guide



Ecosol Off-Line GPT Technical Specifications
 

EcosolTM Off-Line GPTTechnical Specifications


Ecosol GPT Offline Interactive PDF
 

EcosolTM GPT Offline - Interactive PDF - Interactive 3D product drawing - the attached file allows the viewer to zoom in on the product, rotate the product and to view the product and components from all angles. Please note: This is a large file (18mb)

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