Want to keep the trash out of the storm drains?


Nearly 14 years ago, Denis Friezner, invented the stainless-steel storm drain automatic retractable screen (ARS) gate to prevent trash from entering the storm drain. The City of Los Angeles put out a request for companies to design a system to keep the trash from entering the catch basin inlet during dry weather days and was able to unlock /open when the water reaches 50% of the curb height during rain events. Friezner teamed up with the prime contractor Ecology Control Industries for that request. The City of Los Angeles tested the various designs from a number of other companies and decided that he designed the best system. For the next 4 years, he and his team manufactured more than 27,000 ARS systems and 10,000 connecting pipe screens (CPS). With Friezner’s designs and inventions, the City of Los Angeles accomplished Phase 1 of their Trash TMDL Compliance.

Throughout the years, Friezner discovered the limitations and tested to continuously improve his idea and invented the ARS system – a low-cost system with reduced theft value that effectively prevents 98% of trash from entering the storm drain.

Testing, improving and approaching each storm drain with a personal, customized touch is the Hydra way. Friezner, a retired aerospace flight tester, spent 30 years testing the limits of structural loads in flight testing for the military and general aviation to ensure every aircraft was designed as safe and as functional as possible.

Today, as Director of Engineering, Friezner dedicates his time and talent to inventing products that provide simple solutions on a case-by-case basis. Every city, town, and municipality all over the nation faces unique stormwater problems; recognizing the need for a unique, personalized approach to a major problem, Hydra TMDL Systems, Inc., is home to the industry’s most advanced stormwater solutions. Hydra TMDL Systems, Inc. manufactures all their products in-house, with a full array of CNC machinery; hydraulic brakes up to 12-foot 130-tons, shearing up to ½-inch plate, TIG welding, plasma cutting, punch & stamping, injection molding, Haas mills, and lathes.”