Effective Gross Pollutant Traps (gpt) Filtration Systems Brisbane, Queensland As the name suggests gross pollutant traps filtration system is a process that prevents rainwater pollution from getting into the downpipe or waterways. This filter catches the most of the solid dirt, garbage and litters but doesn’t prevent chemicals contaminating to the environment. Types of Gross … Continue reading Gross Pollutant Traps (GPT) Filtration Systems