From whats in the news, CRL lines will run from Jurong, went through West Coast, AMK, Punggol and Pasir Ris, ending at Changi. The project is expected to be completed by 2030 and will connect all existing lines.
The Eastern Region Line ( ERL )will start at Marina bay, goes to Tanjong Rhu, Marine Parade, Siglap, Bedok South, Upper East coast, changi and connect to the future Thomson Line.
As reported, in future punggol residents should be able to travel to Pasir Ris within 10 to 15 minutes instead of taking a bus which is always packed.
My guest should be the same as yours, should be no problem because underground lines like City Hall and Raffles, probably went under Singapore River is still safe so far. These lines are also under many tall office buildings more than 50 storeys high and above.
Engineering structures like Sheare's Bridge is still standing strong after probably 40 years inspite of withstanding heavy moving loads every day.
Future ? presumably nobody knows.