Gnacso
About
Gabriel Novac and Associates (GNA), operating through gnacso.com, is a North American distributor and engineering firm that supplies self-operating, energy-independent technologies for combined sewer overflow management, wet weather treatment, and sewer system maintenance. GNA's entire Hydro-branded product line is designed to function without external electricity, hydraulic power packs, or fresh water supplies, relying instead on gravity, water flow, and closed-circuit hydraulic principles. For sediment management, the HydroSelf flushing device uses a float-controlled gate mechanism that releases a high-velocity flush wave after retention tank drainage, while the HydroSelf Round provides radial flushing for circular tanks, and AutoFlush and HydroFlush handle retention tank and small-diameter sewer cleaning respectively. CSO screening is addressed by HydroClean, a water-wheel-powered brush screen that captures solids down to 4 mm without external energy, along with the HydroScreen FSRF and FSRB overflow screening systems and HydroSpin for continuous floatables retention. Flow regulation products include HydroSlide (constant-discharge float valve), HydroSwitch (gravity-operated flow transfer for polluted base flows), HydroBend (bending weir overflow regulator), HydroStyx (flow decelerator that activates unused sewer storage), and ElectroSlide (level-controlled motorized regulator for 5 to 3,500 L/s). Flood protection is provided by HydroSwizz mobile barriers, HydroBeam stop-log systems, and HydroLatch flood gates. The Hydro MESI particle separator offers compact stormwater treatment, while HydroGuard delivers comprehensive sewer network management for large canals. All products feature stainless steel construction and modular design for retrofit installations.
Key Products
Self-contained flushing device for retention tanks and sewers that uses a float-controlled gate mechanism to produce a high-celerity flush wave after tank drainage, requiring no electricity, maintenance, or fresh water.
Radial flush device for circular and small rectangular tanks, providing the first radial flushing system for round tanks without external power.
Efficient self-flushing system for cleaning stormwater retention tanks and wastewater equalization basins.
Self-flushing siphon device designed to clean small-diameter sewers from 200 to 400 millimeters.
Continuous self-cleaning system for sewage and surface water sewers that operates independently of rainfall events.
Fine screening system for CSO that captures solids down to 4 mm using a water-wheel-powered brush screen requiring no external electricity or hydraulics.
High-performance overflow screen for protecting receiving waters from CSO debris with self-cleaning screening elements.
Arc-screen system for combined sewer overflow screening that captures floatables and protects river banks.
Continuous retention system for floatables in CSO that operates without external energy and has no moving parts.
Flow regulator that maintains constant discharge from sewers without external energy sources using hydraulic principles.
Gravity-operated flow transfer device that routes highly polluted base flows and wet weather floatables without hydraulic or electrical controls.
Overflow regulator that activates only when maximum design water level is reached, preventing premature overflow.
Flow deceleration device that activates unused storage volume in sewer networks to reduce peak discharges.
Level-controlled discharge regulator for flows from 5 to 3,500 L/s that reduces investment costs by approximately half.
Comprehensive sewer management system for large canals and networks that delivers up to 50 percent technology savings and 90 percent simpler construction design.
Mobile flood protection barrier system for rapid deployment during flood events.
Mobile flood protection barrier using laminated stop logs for quick flood defense deployment.
Equipment for flood retention basins and flood gates that protects sewer networks from flood water intrusion.
Compact stormwater treatment device providing effective particle separation in small spaces at reduced cost.
Specialty construction components using first-class materials for reliable long-term functioning in sewer infrastructure.
Service Area
Western US
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