Pay By Mail: Please include your account number on your check and mail it with the payment stub. Please mail them to the following address: Mail to: City of Buena Park Express Mail: City of Buena Park P.O. Box 5009 6650 Beach Blvd Buena Park, CA 90622 Buena Park, CA 90620 2. Pay in Person: You can your water bill in person at 6650 Beach Boulevard, north of Orangethorpe Ave. and south of the I-5 freeway. Forms of payment accepted: Cash, check, Mastercard, Visa, Discover and American Express.