Fill in the blank (_) in the following sentence from the following choices.
Sentence: In the summer it can be tough to maintain the water in the swimming pool. Sometimes the _ gets dirty and needs treating with chemicals.

Choice 1: In the summer it can be tough to maintain the water in the swimming pool. Sometimes the swimming pool gets dirty and needs treating with chemicals.
Choice 2: In the summer it can be tough to maintain the water in the swimming pool. Sometimes the water gets dirty and needs treating with chemicals.
Which of the choices is correct? Respond with only "1" or "2" and no additional text.
2
2.