Besides drain covers, cycling too near the kerb is a bad idea because there are a lot of small debris like broken glass, metal shards etc left there or missed by the sweeper. Bad for tubeless tires.Our highly competent LTA has changed most of the covers across island to “across” rather than “along”. But the point is, never never cycle close to curb side even if that is LTA’s advice. That is the most stupid and dangerous advice ever.