While the beaches in Chennai are dirty, a 45 minute drive down the East Coast Road will lead you to the Ideal Beach Resort. You will pass several other private hotels and beach 'resorts' along the way, but this beach is a clean and popular one for expats living in Chennai. It is not 5 star, but it's a nice escape from the hustle and bustle of Chennai. If you are going to Pondicherry further south, this also makes a nice stop. You can buy an inexpensive day pass (less than $10) or stay overnight. There is a nice swimming pool and a restaurant as well.