The beaches in Singapore are cleaned twice a day during the north-east and south-west monsoon periods when more rubbish is brought to the shore and debris increases, said Minister for Sustainability and the Environment Grace Fu yesterday.
For the other half of the year, the beaches are cleaned four times a week or up to once a day, she added in Parliament.
The comments came amid concerns that the problem of marine trash could be worsening in some countries during the Covid-19 crisis, with a surge in the use and improper disposal of plastics and waste.
Ms Nadia Ahmad Samdin (Ang Mo Kio GRC) asked how marine trash on Singapore's coasts is tackled, beyond beach clean-ups, as well as what the debris typically consists of.
Ms Fu said: "The bulk of our beach litter is marine debris brought in by natural tidal conditions.
"The most common debris are styrofoam, film and hard plastic fragments.
"We can all do our part to keep our beaches clean. This includes demonstrating social responsibility by not littering, as well as supporting beach clean-ups, especially during the monsoon periods."
Photos of plastic items, such as cups and bottles, and styrofoam containers strewn on some of the beaches here emerged in August, prompting questions from the public about why the trash situation looked worse than usual.
At least one volunteer group, Best East Coast Cleanup Plan, organised through messaging application Telegram and which now has more than 2,700 people in it, has been set up in a community effort to maintain Singapore's beaches.
The group, started by Ms Samantha Thian, founder of social enterprise Seastainable, has helped to pick up more than 12 tonnes of rubbish since July.
The National Parks Board and National Environment Agency previously said that despite more people visiting Singapore's beaches since June, the higher amount of trash - up to a 90 per cent increase at East Coast Park during the monsoon months compared with other times of the year - is mostly debris from the immediate region brought in by winds and tides.
Most visitors continue to practise good park etiquette and throw their litter in designated bins, they added.
