Seawater Intake and Marine Outfall Systems Seawater intake systems and outfalls, Elmosa.
 Seawater Intake Systems - Smart Super Seawater Intake Technology with Site Recognition Capabilities. Read more
O&M Free, no O&M Costs associated with system operation
The low velocity InvisiHead detects pump energy pulses, recognizes site characteristics, operation conditions, and application requirements, and commences flow management as planned.  It filters the water and delivers high-quality flow. Low Capital Costs, 0-O&M Costs-see the table below.
BTA as per
US EPA Section 316(b), the InvisiHead meets and exceeds the Final Cooling Water Intake 316(b)Rule requirements
The proven
InvisiHead technology  is used as an intake head or outfall diffuser in either fresh or salt water ; capacity unlimited. 
ASE Contact


Elmosa, USA

Self-flow Management


Scour proofing
Robust Structure

Flow Hydraulics Compariso
InvisiHead/Wedge wire Comparison

Offshore Platform/Pump Strainer
InvisiHead outlet on top platform-fitted

Offshore Platform on Floor
InvisiHead outlet on top anchored to sea floor

 Omni directional outfall

Platform Outfall
Platform-fitted outfall

Elmosa Complete System
Elmosa complete seawater intake system

Plan of elmosa intake and outfall

Elmosa Complete Outfall
Elmosa outfall system

Outfall Flow Mngmnt
Outfall 3-D dispersion & dilution management
High dilution ratio is reached near the outfall

Required dilution reached at the start of the near filed mixing zone
NatSep Sediment Separation
The NatSep sediment separation basin

Anti biofouling chemical dispensing system
InvisiHead built-in anti biofouling injection system


ASE Contact

The InvisiHead is Environmentally Smart Responsible Proactive Non-Reactive, Excludes sediment, marine life and debris, Durable, Reliable, Selective Seawater Intake & Outfall System. It is Self-Reliant, no O&M, no moving parts, no spare parts needed, no backwash or air burst or any kind of operation or maintence work. The only water intake system that pays its capital costs and makes money
Why should you install the InvisiHead?. Why South Wales Next Generation 1,000,000 m3/d RO plant consultant selected the IH system.
Potential Users: Power and Desalination Plants, Petrochemical and Gas Complexes, Refineries, Aquaculture and Fish Farms, Municipal Systems, HVAC, Etc.

This virtually unlimited flow capacity intelligent site recognizing intake head holistically protects aquatic life; no impingement or fish mortality; it is unattractive to aquatic organisms, sediments, seaweed, or debris; it is selective and delivers clean water; it utilizes local marine currents to sweep away and into the ambient again seaweeds, fish-small and young, jellyfish, sediments and debris if they enter the InvisiHead. The no-return flow is at the outlet. It is out of phase of the major flow channel by 90 thus providing safe passage to marine life to get back into the environment again through the opposite end. In its return to the ambient, flow is in phase with the local currents direction thus all types of onshore mechanical screening-fixed or traveling or both-are no longer required. Negligibly low head loss at 0.00017m or a pressure drop of 0.017mb means almost 0$ spent on energy. Nearly all pumping energy goes to overcome friction at the intake pipe. As an outfall, the InvisiHead safely discharges, disperses, mixes and dilutes RO brine, cooling water, and wastewater. The discharges reach equilibrium and disappear into the ambient within the vicinity of the outfall at the beggining of the near field mixing zone. The InvisiHead operates in full compliance with the US EPA Section 316(b) of the Clean Water Act governing the use of cooling water at power plants and industrial facilities (the Final Rule). It Protects biodiversity values of the site and avoids impacts to native vegetation or fauna. No ecological adverse effects are associated with The InvisiHead.

The genuine and original Site-Specific Selective InvisiHead and NatSep technologies reside here at American Eco Systems

Starting January 2013 the InvisiHead
flow transition through the sequential 4 flow phases have been upgraded to further improve water quality and drastically reduce or eliminate flow of sediments or seaweed  if present in the water column; velocities: approach 0.002m/s (0.0066 fps), inlet 0.09m/s (0.295 fps), outlet: 0.11-0.12m/s (0.36-0.39 fps). No environmental adverse impacts are associated with seawater intake of cooling water or concentrate discharges; low on SDI, ideal for RO systems. Site and application recognition enables the InvisiHead to fine-tune its flow-management operation and reduce SDI.

Operation-free. Maintenance-free intake system, the InvisiHead
 Payback period in the form of O&M cost savings is short; savings in capital and O&M expenses are high


See Cost_Comparison_between_the_InvisiHead_and_wedge-wire_screen_intakes and InvisiHead technical and cost comparison with onshore traveling screens

NO MORE TROUBLES: Just turn-on the seawater pumps at the pump house and relax. No more clogging. No more pressure drop. No more alarms. No more backwash or air bursting. No more dead fish or any of the aquatic life. No more marine growth or sediments settling in the intake pipe. Simply, no more worries and no more operation or maintenance. All remain in DAY 1 condition for decades to pass.

Seawater Intake & marine outfall System - the philosophy behind the design: let nature manage system operation

Milestone dates: 1981/1982 the InvisiHead was conceived, researched and developed at the reputed St. Anthony Falls Hydraulic Lab of the University of Minnesota; 2002 the InvisiHead has become a BTA as per the US EPA designation; 2009 Australian Ministry of Environment and Australian EPA approved the InvisiHead outfall to be installed in Australian waters; 2009 an Australian mining company selected the InvisiHead for their RO plant intake and brine discharge; in 2010 a British consulting group selected the InvisiHead to serve Sydney's Next Generation's one million m3/d RO desalination plant to supply 2.4 million m3/d of seawater and discharge 1.4 million m3/d; 2013 InvisiHead structure-embedded site and application recognition ability was further fine-tuned to better improve flow management;  2014_water_enters_InvisiHead at 0.09m/s and leaves it at 0.11-0.12m/s to allow supremacy to marine currents to flush out any fish, sediments, or seaweeds if found.

The American Eco Systems introduces the Elmosa offshore seawater intake and marine outfall systems - the InvisiHead. InvisiHead flow streamlining is improved in 2012 for better performance. It's specially fit for RO systems due to its high reduction of suspended matter resulting in a lower SDI
Supported IH
Click here to enlarge

We are seawater intake system consultants as well as InvisiHead designers and fabricators. The InvisiHead is a selective water intake system, it lets water in and leaves sediments seaweed and marine life behind. It is a robust stable structure built to remain in full operation even during stormy conditions. It is designed to withstand SS Cat 5 hurricanes. It should be installed off the surf zone.


In 2012 AES updated and enhanced the flow streamlining of the InvisiHead Intake and outfall systems and improved the hydraulic tuning of the flow streamlines within the approach, entrance, and outlet phases in order to increase the degree of exclusion of marine life, sediment and debris. Avoidance: The change in flow pattern created by the InvisiHead triggers more avoidance response mechanisms in fish both juvenile and adult, thereby avoiding their inflow. The structural integrity of the InvisiHead has been also reinforced to stand up to G5 hurricane force. The IH systems are made of high grade thick stainless steel plates to preserve structural integrity of the systems and remain in full operation during the structure's lifetime of over 50 years. At American Eco Systems time freezes.


For the proper design of the seawater intake and outfall, the InvisiHead system has been developed to be the system of choice that naturally handles the flows in both directions. The InvisiHead seawater intake head. The InvisiHead intake and outfall systems operate to remain in full compliance with the requirements of Section 316(b) of the US EPA Clean Water Act. Both systems meet and exceed the requirements by 40%. The Act requires an intake entrance velocity not to exceed 0.15 m/s. The InvisiHead's is 0.09 m/s. The InvisiHead supports biodiversity, protects and preserves the ecosystem.  it is environmentally friendly in both directions: water withdrawal and discharge. American Eco Systems takes environmental protection and preservation seriously as a top priority that is integrated into system design and operation.

The InvisiHead system works as a superb marine outfall. The dispersion process of effluents is unmatched by any other technology including the widely-used linear riser - diffuser systems. Dilution and blending occurs within a short distance from the radial pointsource. AES has secured the outfall design to remain in full compliance for many decades to come. Both the Australian Ministry of Environment and EPA favored The InvisiHead intake and outfall over the existing linear diffuser types to be installed in Australian offshore waters. See the image below and also see,_Australian_project.pdf, and  ABTP-Outfall-Modeling.Report.


RO Brine dispersion

Flow velocities into the InvisiHead intake head and out of the InvisiHead outfall:

  • 0.002 m/s max. (0.006 fps) <5 meters (15 ft) away from entrance, approaching or dispersing,
  • 0.03 m/s max. (0.1 fps) 1.0 meter (3 ft) away from entrance, approaching or dispersing,
  • 0.09 m/s max. (0.3 fps) at the circumference, entering or releasing,
  • 0.11-0.12 m/s max. (0.4-0.5 fps) at InvisiHead intake outlet. 
Head loss at the InvisiHead approaches zero at 0.00017m. It is engineered to control and drastically reduce or eliminate the inflow of debris, the ingress of fish, mussels and other marine life.
InvisiHead comparison with wedge-wire screen intake heads

InvisiHead system for use as pump strainers, intakes, or discharge marine outfalls in offshore uses and in oil and gas platforms

The InvisiHead operating as a seawater intake or a pump strainer
IH strainerInv.
System fixed to platform, see details
IH strainer
System fixed to the sea floor serving the platform, sea details

The InvisiHead operating as a marine outfall
outfall inv.
System fixed to platform, sea details
System fixed to the sea floor serving the platform, sea details



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