Smoking festival at Dhanmondi

Ganja, a highly potent form of cannabis, is most commonly used in all the areas of Dhanmondi. Ganja has effect on the mental state and this is the main reason why most people smoke ganja. Ganja can change one's mood. Students are mainly falling prey to this.
In Dhanmondi after Maghrib prayer when one goes out, especially for jogging, s/he gets disgusted with the smell of ganja. People from all over Dhaka come to Dhanmondi Lake to smoke ganja whenever they feel like.
Law enforcers do visit the area occasionally but this does not work. Can't we do anything to save our youth from this addiction? The govt. has banned smoking in public places, but do come to Dhanmondi Lake, you will see festival of smokers.