13 Riverside Avenue • Mastic Beach, NY 11951

$549,000 Beds: 3 • Baths: 3 full • Sq. Feet: 2340 • MLS ID: 955402 • Subdivision:School Dist: William Floyd
Waterfront living with endless potential on Poospatuck Creek, offering direct access to the Forge River and beyond. This split-level home is all about location, views, and opportunity. The upper level features an open floor plan designed to capture the water from every angle, with three sliding glass doors that open to a sprawling upper deck, perfect for entertaining, relaxing, and soaking in the scenery.Enjoy 100 feet of bulkhead and your own private dock, ideal for boating, kayaking, paddle boarding, or simply enjoying life on the water. Wake up to stunning sunrises and wind down with peaceful sunsets reflected across the creek. This setting delivers true waterfront serenity.The home offers two additional rooms with flexible use, ideal for a home office, gym, game room, or creative space. Buyers may also choose to add wardrobes to use these rooms as additional sleeping areas.The lower level includes exterior entrances, creating excellent potential for a guest suite or accessory apartment with proper permits. Whether you envision multigenerational living, rental income, or flexible work-from-home space, the layout supports a variety of possibilities This home offers a fantastic opportunity for buyers ready to bring their vision and create a custom waterfront retreat tailored to their style. With an unbeatable waterfront setting, this is a rare chance to own property with direct access to the Forge River and the Great South Bay. View this listing at: http://www.laffey.com/lid=184152372

Property Features

  • Garage: 1
  • Taxes: $12,175
  • Fenced: Yes
  • Exterior: Vinyl Siding
  • Special View Info: Water
  • Lot Size: 0.25 Acres
  • Heating: Baseboard,Hot Water,Oil
  • Cooling: Wall/Window Unit(s)
  • Year Built: 1972
  • Water: Public
  • Sewer: Cesspool
  • On Market Date: 2026-01-27
  • Appliances: Gas Oven
  • Fencing: Back Yard,Fenced,Vinyl
  • Frontage: 100 Feet
  • GarageY/N: Yes
  • Interior Features: First Floor Bedroom,First Floor Full Bath,Eat-in Kitchen,Open Floorplan,Primary Bathroom,Washer/Dryer Hookup
  • Attic: Full,Pull Stairs
  • Number Of Kitchens: 1
  • Heating Zones: 2
  • Parcel Number: 0200-940-00-05-00-029-000
  • Parking Features: Driveway,Garage
  • Rental Term: Monthly
  • Rooms Total: 10
  • Utilities: Cable Available,Electricity Connected,Propane,Trash Collection Public,Water Connected
  • Waterfront Features: Bulkhead,Creek,River Access,Water Access,Waterfront

School Information

  • High School: William Floyd High School
  • Middle School: William Paca Middle School
  • Elementary School: Tangier Smith Elementary School
  • School District: William Floyd
Printed June 08, 2026


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