In a small saucepan, bring 1 cup water to a boil. Add rice and stir. Reduce heat, cover and simmer for 20 minutes.
In a large saucepan or stockpot, saute the onion and garlic in butter until tender. Add clams, corn, lemon juice and tomato sauce. Season with fresh basil and salt and pepper to taste. Stir in remaining cup of water and let the soup simmer for 20 minutes. Remove from heat and stir in the heavy cream and cooked rice until well blended. Serve immediately.