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Seawater Intake Solutions

Engineering Excellence for Marine Environments

Seawater intake systems are critical infrastructure for coastal industrial facilities, desalination plants, and power stations. Our engineered solutions address the unique challenges of marine environments, including biofouling, corrosion, debris entrainment, and environmental protection, ensuring reliable water supply while minimising ecological impact.

35,000+
m³/h Max Flow
99.5%
Debris Removal
25+
Years Design Life
Super
Duplex SS Options

Challenges & Solutions

Addressing Marine Environment Complexities

Marine Biofouling Biological growth on intake structures and screens reducing flow capacity

Marine organisms including barnacles, mussels, algae, and bacteria rapidly colonize submerged surfaces, forming biofilms that restrict flow, increase pressure drop, and accelerate corrosion. Unchecked biofouling can reduce intake capacity by 50% or more within months.

Our Solutions

  • Chlorination Systems: Continuous or shock-dose sodium hypochlorite injection for effective biofouling control
  • Copper-Nickel Alloys: 90/10 Cu-Ni intake screens with natural antifouling properties
  • High-Velocity Design: Self-cleaning velocities (>2 m/s) that prevent larval settlement
  • UV Treatment: Non-chemical biofouling control for environmentally sensitive areas
  • Air Bubble Systems: Air curtain technology to deter fish and reduce biofouling

Saltwater Corrosion Aggressive marine environment causing rapid material degradation

Seawater's high chloride content (19,000-21,000 mg/L), combined with dissolved oxygen and biological activity, creates highly corrosive conditions. Standard carbon steel can fail within months, while even 316 stainless steel experiences pitting and crevice corrosion in warm waters.

Our Solutions

  • Super Duplex Stainless Steel: 2507 grade for critical components with PREN > 40
  • 90/10 Copper-Nickel: Superior corrosion resistance with natural biofouling resistance
  • Titanium Components: For extreme environments and heat exchanger applications
  • Protective Coatings: Marine-grade epoxy and glass flake linings for structural elements
  • Cathodic Protection: Sacrificial anode and impressed current systems for submerged structures

Debris & Sediment Entrainment Seaweed, plastic, sediment, and marine debris blocking intake systems

Coastal waters contain significant debris including seaweed, plastic waste, jellyfish blooms, and suspended sediment. Without effective screening, this material can clog pumps, damage heat exchangers, foul membranes in desalination plants, and cause unplanned shutdowns.

Our Solutions

  • Multi-Stage Screening: Coarse bar screens (50-100mm) followed by fine mesh screens (3-10mm)
  • Travelling Water Screens: Automated continuous cleaning with debris compaction
  • Drum Screens: High-capacity rotary screens for large flow applications
  • Self-Cleaning Filters: Automatic backwash systems for fine filtration
  • Sediment Traps: Velocity reduction chambers for sand and silt removal

Environmental Protection Minimising impact on marine life and meeting regulatory requirements

Seawater intakes can entrain fish larvae, eggs, and adult fish, while impingement on screens can injure or kill larger organisms. Regulatory bodies worldwide are imposing stricter requirements for intake design to protect marine ecosystems.

Our Solutions

  • Velocity Caps: Low-velocity intake heads (<0.15 m/s) to reduce fish entrainment
  • Subsurface Intakes: Beach wells and infiltration galleries that naturally filter seawater
  • Fish-Friendly Screens: Wedge wire screens with 1-3mm slots and low approach velocities
  • Air Bubble Barriers: Behavioural deterrent systems to guide fish away from intakes
  • Seasonal Screens: Fine mesh during spawning seasons to protect larvae

Extreme Marine Conditions Storms, waves, tidal variations, and ice affecting intake reliability

Seawater intakes must withstand harsh marine conditions including storm waves, tidal ranges up to 12 metres, currents exceeding 3 m/s, and ice formation in colder climates. Structural failure can result in catastrophic water supply interruption.

Our Solutions

  • Robust Structural Design: Designed for 100-year storm conditions and wave loading
  • Flexible Intake Configurations: Multiple intake points to ensure supply during maintenance
  • Ice Protection: Heated intake structures and air bubbling systems for cold climates
  • Tidal Compensation: Variable speed pumps and level-controlled systems
  • Breakwater Protection: Designed intake locations with wave attenuation structures

Water Quality Variability Seasonal changes in turbidity, temperature, salinity, and algal blooms

Seawater quality varies significantly with seasons, weather events, and location. Red tides, storm runoff, and seasonal temperature swings can challenge treatment systems and affect downstream processes including membrane performance and cooling efficiency.

Our Solutions

  • Multi-Level Intakes: Adjustable withdrawal depths to access best quality water
  • Pre-Treatment Systems: Coagulation, flocculation, and dissolved air flotation for algal blooms
  • Granular Media Filtration: Sand and anthracite filters for turbidity removal
  • Online Monitoring: Continuous turbidity, chlorophyll, and temperature monitoring
  • Redundancy: Parallel treatment processes for handling variable loads

Intake Configuration Types

Tailored Designs for Every Application

Open Ocean Intakes

Direct offshore intakes with submerged intake heads for large flow applications.

  • Flow rates: 1,000 - 500,000 m³/h
  • Depth: 5 - 30 metres offshore
  • Velocity cap design available
  • Multi-cell configurations
  • Concrete or steel structures

Beach Wells

Subsurface intake through beach geology providing natural filtration.

  • Flow rates: 100 - 50,000 m³/h
  • Natural pre-filtration
  • Minimal environmental impact
  • Lower biofouling tendency
  • Vertical or horizontal wells

Infiltration Galleries

Subsurface collection systems beneath the seabed for passive filtration.

  • Flow rates: 500 - 100,000 m³/h
  • Excellent water quality
  • No impingement/entrainment
  • Low maintenance requirements
  • Slotted pipe or caisson design

Jetty/Wharf Intakes

Intake structures integrated into existing marine infrastructure.

  • Flow rates: 500 - 200,000 m³/h
  • Utilises existing structures
  • Reduced capital costs
  • Easy access for maintenance
  • Side-entry or bottom-entry

Typical Seawater Intake Process

From Ocean to Process

1

Intake Structure

Offshore headworks or beach well with velocity cap

2

Coarse Screening

Bar screens 50-100mm for large debris removal

3

Fine Screening

Travelling screens or drum filters 3-10mm

4

Chlorination

Biofouling control with hypochlorite dosing

5

Filtration

Self-cleaning filters or media filtration

6

Process Supply

To desalination, cooling, or industrial process

Technical Specifications

Engineering Parameters & Material Standards

ParameterSpecificationNotes
Design Flow Range100 - 500,000 m³/hCustom designs available for any capacity
Intake Velocity0.1 - 0.5 m/s (through screen)Lower velocities for fish protection
Screen Aperture1 - 100 mmMulti-stage screening typical
Operating Depth3 - 50 metresDependent on intake type
Standard Materials316L Stainless SteelFor temperate waters
Premium MaterialsSuper Duplex 2507, 90/10 Cu-NiFor tropical/aggressive environments
Structural Design Life25 - 50 yearsWith proper maintenance
Design StandardsAPI, ASME, EN 1993, DNVProject-specific compliance
Chlorine Residual0.5 - 2.0 mg/L (continuous)Or shock dosing 5-10 mg/L

Why Choose Our Seawater Intake Solutions

Engineering Excellence & Reliability

Environmental Compliance

Our designs meet or exceed international environmental regulations including US EPA 316(b), EU Water Framework Directive, and local marine protection requirements.

Low Lifecycle Costs

Superior material selection and design optimisation minimise maintenance requirements and extend service life, reducing total cost of ownership.

Integrated Solutions

Complete turnkey packages from intake structure through pre-treatment, with single-source responsibility for design, supply, and commissioning.

Global Experience

Proven designs deployed across diverse marine environments from tropical to arctic, shallow coastal to deep offshore installations.

High Availability

Redundant configurations and robust design ensure >99% water supply availability, critical for continuous industrial processes.

Sustainable Design

Environmentally responsible solutions that protect marine ecosystems while meeting your water supply needs.

Related Equipment & Services

Complete Seawater Treatment Solutions

Filtration Systems

Self-cleaning filters and media filtration systems for seawater polishing before membrane processes or heat exchangers.

View Filtration Systems

Water Screens

Travelling water screens, drum screens, and bar screens for debris removal at seawater intakes.

Explore Wastewater Screens

Chlorination Systems

Sodium hypochlorite generation and dosing systems for effective biofouling control in seawater systems.

View Chemical Treatment Services

Desalination

Complete seawater desalination solutions including pre-treatment, RO systems, and post-treatment.

Desalination Plant Solutions

Related Pages

Design Your Seawater Intake System

Contact our marine engineering team to discuss your coastal water supply requirements. We'll design a customised intake solution that ensures reliable operation while protecting the marine environment.

Industries We Serve

Our expertise spans multiple industries with sector-specific water treatment solutions.