Polylok 20" x 12" Septic Tank Riser

The Polylok 20" x 12" Septic Tank Riser (Model 3009-R12) is a tall, efficient extension riser that simplifies bringing septic tank or distribution box access to ground level with fewer sections. At 12" tall (1 foot), this riser reduces the number of connections and screws needed compared to stacking multiple shorter units—ideal for moderate to deeper burial depths while maintaining full stackability in the Polylok 20" series.

Crafted from rugged high-density polyethylene (HDPE), it delivers outstanding durability, UV resistance, and performance in demanding septic environments—outlasting brittle alternatives and easier to install than concrete.

POLYLOK RISERS NO LONGER COME WITH A FACTORY INSTALLED GASKET. We recommend using our butyl sealant tape to create a seal between risers.

In Stock

$82.00MSRP: $95.00

Item #:3009-R12

Manufacturer:Polylok

Key Features and Benefits

Tall 12" Design — Provides substantial height per piece for quicker builds to grade; fewer screws and joints mean faster, more reliable installations.
Stackable System — Interlocks seamlessly with other Polylok 20" risers (6", 2", etc.) or adapter rings; combine for precise custom heights without cutting.
Secure Locking — Snaps/locks together and fastens with included stainless steel screws (use alternating pattern for even pressure and optimal seal integrity).
Watertight and Airtight Capability — Enables effective vacuum or water testing of septic tanks/distribution boxes; POLYLOK RISERS NO LONGER INCLUDE FACTORY GASKETS—apply butyl sealant tape (ASTM-C990 compliant) between sections for dependable sealing against infiltration.
Reinforced Strength — Heavy-duty internal structural ribs add rigidity; supports pedestrian traffic and light loads like lawn mowers or small garden tractors when properly installed and backfilled.
Highest UV Protection — Premium UV-ray resistance prevents fading, cracking, or brittleness from long-term sun exposure.
Frost-Resistant — Structural ribs help prevent frost adhesion in cold climates.
Lightweight & User-Friendly — Significantly easier to transport, handle, and install than concrete risers, saving time and labor.
Versatile Use — Compatible with Polylok distribution boxes for easy grade access.
Made in the USA — Patented Polylok quality from a leader in onsite wastewater solutions.

Specifications

Diameter: 20 inches
Height: 12 inches
Material: High-density polyethylene (HDPE)
Color: Green
Compatibility: Fits Polylok 20" risers, adapter rings (#3009-AR square tank adapter or #3009-RTR20 round tank adapter), and Polylok 6-Hole (#3017-6H) or 8-Hole (#3017-8H) distribution boxes. Not interchangeable with other brands without adapters.
Included: Riser section + stainless steel attachment screws

Important Note: Always use butyl sealant rope/tape between joints for watertight performance, as no factory gaskets are included on current models.