A Foyle MLA is calling for a strengthening of legislation to protect the River Foyle and other waterways.
Sinead McLaughlin was speaking after she was told that there have been four prosecutions for pollution on the Northern side of the River Foyle over the last five years, leading to fines totalling just £3,500.
Responding to questions posed in the Assembly by McLaughlin, Minister Poots said there had been four prosecutions.
Two were brought by the Northern Ireland Environment Agency and were concluded in 2016. One related to a company prosecuted for a pollution detected in 2015, which was fined £1,000, the other was a company causing pollution in 2016 which was fined £2,000.
The Loughs Agency can also take action, and it took two prosecutions relating to water pollution in the River Foyle, both heard in 2017. One individual was fined £500, while one company was convicted, but not fined.
Ms McLaughlin has written to Minister Edwin Poots saying much stronger sanctions are needed, along with new laws to ensure better protection.
