Are trash racks an effective solution? It seems cheaper to simply put some nets across the water channels?
No. Trash racks suffer from very low capture rates (between 5-15%) and often fail to collect smaller gross pollutants such as cigarette butts etc. More importantly, they do not have an overflow mechanism and are prone to block, potentially causing serious flooding during major storm events. They also require frequent cleaning, which is usually difficult and costly, and are also visually unattractive. Ecosol’s Net Tech product is the exception to most netting units available in that is it is very affordable, has an effective overflow mechanism and captures more than 91% of gross pollutants greater than 19mm. Even in the 1990s, many engineered at-source litter baskets and in-line/end-of-line gross pollutant traps (GPTs), while a significant improvement on earlier devices, still suffer from the above and other limitations, including: • High headloss; • Low treatable flows; • No overflow by-pass; • Remobilisation of captured pollutants; and • High cleaning and maintenance costs. Not surpri
