Unless you live in one of the high-rise hotels, you will need some kind of transport to get to the beach. Most, if not all beaches close to Doha are part of any of the high-rise hotels. However, most of them will let you use the beach for free. Haven't tried the Sheraton which is the closes to the city but was well received in the Intercontinental for free.
Another option I haven't tried is palm tree island. There are several companies linking this island with central Doha by dhow or boat.
Qatar may be building a considerable amount of cultural, and now sports, infrastructure, but it is not above trying to lure some of those tourists who are looking for a sun holiday. Doha now has two public beaches, and one of them is the Katara Beach, which is adjacent to the cultural village of the same name. In truth, I am not sure exactly when people envision being able to come to the beach in Qatar, as the effect of both the humidity and the 50 degree days during the summer make it virtually impossible not to become dehydrated in under five minutes. In the winter, temperatures are certainly cooler, but the region does have rain storms and, more frequently, dust storms. Nevertheless, the sand here is clean and the water is a beautiful shade of blue, so for those few days when the conditions are ideal it may actually be a bit of paradise in the Persian Gulf.
We were at a nice beach at Katara and I was surprised why there is nobody out swimming. I find out that those who wish to swim and enjoy any beach here in Qatar they have access only if they pay a fee. It is something like 22 euros per person or Qr. 100.
It is ridiculous to have to pay that much per person just to have access to the beach. So you hardly see anybody swimming even though there is sea around. Imagine if all these beaches were full of ladies in black up to their ankles! It would not add to the country’s tourism.
I believe this is the reason they ask for a fee.
People living in Doha who wish to swim usually go to different beach clubs or hotels and the fee is between Qr.150 during the week, and goes up to Qr. 250/300 per day per person on the weekends. Typically rates would include access to the beach, towel, service and use of pool.
Information of this place couldn't be easily found in google search. Probably because of this, there were not many tourists. Leaving was also a problem. No taxi came around. I had to walk 10-15 mins to the nearest hotel, InterContinential, to catch a taxi.
The place had a private beach, charging QAR100 for admission from 9am-5pm, a few restaurants and a amphitheater. All shops were vacant. The restaurants were not busy. I went to a Turkish one and they didn't serve food but drinks and sheesha.
One attraction of Doha is the ease with which you can leave it. In less than 15 minutes, you can find yourself on a sandbar in the middle of the bay, relaxing beachside as you wait for your kebab to be peeled from the barbecue grill. Palm Tree (or Al Nakhil) Island offers clean beaches, landscaped gardens and a decent selection of indoor and outdoor dining, all in a quiet, traffic-free environment. You can catch the dhow from a jetty near the Sheraton in Doha Bay.