Capability · Gates, Intakes & Flow Control

Keep flow control working below the waterline.

Sluice gate repair, seal replacement, trash rack cleaning, stoplog placement and differential pressure safety, for the gates and intakes that control flow through water, dam and industrial infrastructure.

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Crew lifting a gate frame at a dam control structure.

Gates

Sluice, Crest & Control

Seals

Replacement & Seating

Intakes

Trash Rack & Screen Work

Safe

Differential Pressure Planning

Overview

When the gate is the problem.

A gate that won't seat, an intake that's blocked, a seal that leaks, flow control problems are usually submerged, and they rarely wait. Zion Marine inspects, repairs and restores gates, intakes and flow control systems without draining the structure they protect.

When this capability is needed.

Gate conditions

Gates that won't seat or seal
Leaking seals or seats
Binding or jammed gates
Corroded or damaged gate components

Intake conditions

Blocked or fouled trash racks
Restricted intake flow
Damaged screens or racks
Debris accumulation

Planned & construction work

Stoplog or bulkhead placement
Gate removal or installation
Inspection-driven repairs
New construction support

Methods and deliverables

Services on gates and intakes.

Depending on the structure and condition, services may include:

Inspection
Debris removal
Cleaning
Repair
Removal
Installation
Mechanical work
Seal inspection and replacement
Guide and frame inspection
Structural inspection
Dredging around structures
Isolation and lockout/tagout evaluation
Differential pressure assessment
Flow control planning with facility staff
Standby diver and emergency procedures
Documented dive plan

Traveling water screen with chain drive and mesh panels.

Gates, Intakes & Flow Control

Traveling Water Screens

Traveling water screens keep debris out of plant intakes. When one is damaged or passing debris, flow and equipment are at risk. Zion Marine divers inspect and repair traveling water screens underwater. It is work we do often.

Underwater inspection of traveling water screens and the intake around them.
Underwater repair of damaged screens.

Workflow

From field condition to usable documentation.

A structured path from the initial review to a deliverable the owner or engineer can act on.

Isolation & lockout/tagout

Flow, isolation and differential pressure are evaluated and locked out before any diver enters the water near a gate.

Inspection & diagnosis

The gate, seals, seating and intake are inspected to find the actual cause of leakage, binding or flow restriction.

Repair or replacement

Seals are replaced, gates are adjusted or repaired, and trash racks and screens are cleared or restored.

Verification

The repaired gate or intake is verified to seat, seal and flow correctly before the system returns to service.

Where it applies

Infrastructure and markets this capability serves.

Sluice Gates

Slide and control gate systems.

Intake Gates

Structure inlets and controls.

Trash Racks

Debris bars and screens.

Stop Logs

Temporary isolation systems.

Bulkheads

Isolation and closure structures.

Valves

Submerged valve assemblies.

Outlets

Low level outlets and conduits.

Screens

Intake screens and systems.

Dams & Water Control

The primary market for this capability.

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Water & Wastewater

Treatment plant gates and intakes.

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Industrial Infrastructure

Industrial intake and screen systems.

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Government & Federal

Public dam and utility structures.

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Operating conditions

Pressure is the primary hazard.

Flow control work cannot always occur under active differential pressure, and Zion Marine does not pretend it can. Every gate and intake project is evaluated individually for isolation, flow, access and safety before the method and crew are determined.

Evaluated per project

Differential pressure
Isolation availability
Flow conditions
Access and clearance
Structure geometry
Operational limitations
Facility coordination

Surface-supplied diving

Infrastructure work is performed with surface-supplied diving: umbilical gas, voice communication, topside supervision and a standby diver. Why that matters →

In practice

Related gates, intakes & flow control projects.

Project examples tagged to this capability in the Project Library.

Crew working at a chlorine contact chamber at the R.M. Clayton water plant.

Dams

R.M. Clayton Water Plant Improvements

Owner: City of Atlanta · Levee: U.S. Army Corps of Engineers · GC: Astra Group · Atlanta, Georgia · 2025–2026

Two scopes at the City of Atlanta's R.M. Clayton water plant. At the levee outlets, underwater installation of four custom backflow prevention devices: a 9 ft hinged valve, a 48 in duckbill check valve, a fabricated sliding gate and an 8 x 7 ft hinged valve, with fabrication support, rigging and diver installation. At the plant, chlorine contact chamber modifications.

DamsGates & Flow ControlFederal

Dive spread with helmets and umbilicals laid out on the deck at the Carters Lake dam.

Dams

Carters Lake Pump Storage Facility Nose Cone Replacement

Owner: U.S. Army Corps of Engineers · Georgia

Nose cone replacement at the U.S. Army Corps of Engineers Carters Lake pump storage facility in Georgia.

DamsUSACEFederal

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Licensed general and marine contractor. ADCI-certified divers and supervisors. TRIR 0.0 as of 2026, EMR 0.83 as of 2026. Full credentials on the Qualifications page.

Related resources

Guides on this capability.

Underwater Inspection

Planning an Underwater Infrastructure Inspection

What to gather before scoping a dive inspection at a treatment facility, dam or bridge.

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Aerial view of a dredge working beside a dam outlet.

Dredging & Sediment

Dredging Around Critical Infrastructure

How diver-guided dredging protects intakes, screens and structures during sediment removal.

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Continuity of service

Sediment is often part of the problem.

Blocked intakes and restricted gates are frequently complicated by sediment accumulation. Zion Marine pairs gate and intake work with targeted dredging to restore full flow capacity.

Explore Dredging & Sediment Removal

What that can include

Forebay and intake dredging
Sediment removal around structures
Debris clearance
Capacity restoration

Intake rack lowered into a lake by crane.

Tell us about the structure and the condition

Have a gate, intake or flow control issue?

Tell us about the structure and the symptom. We'll help determine the right inspection or repair scope.

Discuss a Project Call (423) 343-5312 View Related Projects Emergency Assistance