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Septic Tank Risers, Lids & Accessories

Septic Tank Risers, Lids & Accessories

Septic Tank Risers and Lids

Septic tank risers bring the tank's manhole up to ground level, so you can open the lid for pumping and inspection without digging. A riser is a polyethylene extension that stacks on the tank's manhole, and a lid closes off the top. This page carries Norwesco and Snyder risers, riser-and-lid combos, manhole extensions, replacement lids and the small parts that go with them: gaskets, septic adapters and screws.

How to pick the right riser

  • Match the brand and the manhole size. Risers are made for a specific maker's manhole. Norwesco risers fit Norwesco tanks, and Snyder risers fit Snyder tanks. Most Norwesco septic, cistern and multi-use tanks have a 20 inch manhole. The 10,000 to 20,000 gallon underground tanks use 24 inch manholes and their own riser (N-64410).
  • Measure the depth. Measure from the top of the tank's manhole to finished grade, then choose an extension height that reaches it: 6, 15 or 24 inches. Extensions can be stacked for deeper burial.
  • Count the manholes. Many 1,000 to 1,750 gallon tanks have two manholes. Order one riser or extension for each manhole you want brought to grade.
  • Finish with a lid. The riser-and-lid combos (N-62395, N-63831, N-63830) include the lid. Plain extensions reuse the tank's existing lid on top.

Norwesco risers, extensions and lids

Part #What it is
N-63514 / N-62397 / N-6239620" diameter manhole extensions, 6" / 15" / 24" tall (Norwesco septic and multi-use tanks)
N-63832 / N-63833 / N-63834Manhole extensions, 6" / 15" / 24" tall (Norwesco underground water cisterns)
N-6239520" lid with a 12" diameter x 25" tall riser
N-6383123" riser with 12" lid
N-6383036" riser with 6" lid
N-6240820" domed septic and water tank lid
N-6367220" lid for the 2,600 and 2,650 gallon below-ground tanks
N-644106" riser for the 10,000 to 20,000 gallon underground tanks (24" manhole)

Snyder risers (SII-RISER12, SII-5160000W94201) and the Snyder 24" septic manway (SII-34300018) are listed below with the Norwesco parts.

Questions buyers ask

Do I need a riser? Risers aren't required, but they turn every pump-out into a lift-the-lid job instead of a dig. Many counties require access at or near grade on new systems, so check with your local health department.

Will a riser fit my existing tank? Yes, if it's made for your tank's brand and manhole diameter. Tell us the tank's brand, part number or manhole size and we'll match it: 866-418-1777.

Can I order risers with a tank? Yes. Every Norwesco septic, cistern and underground tank page lists the risers and extensions made for it, so they ship together on one freight quote.

Shopping for the tank itself? See Septic Tanks, Cistern Tanks and Norwesco Underground Water Tanks.

  • Norwesco

    SKU: N-63870

    Norwesco Self Tapping Screws

    $1.00
    The item has been added
  • Norwesco

    SKU: N-61765

    Norwesco Service Weight or Schedule 40 Gasket Kit (2 ea)

    MSRP: $15.00
    $13.66
    The item has been added
  • Norwesco

    SKU: N-62408

    Norwesco 20 Inch Domed Septic/Water Lid

    $30.00
    The item has been added
  • Norwesco

    SKU: N-63152

    Norwesco Septic adapter SCH40 with nut & EPDM gasket

    $34.00
    The item has been added
  • Norwesco

    SKU: N-63672

    Norwesco 20 Inch Underground Tank Lid

    $50.00
    The item has been added
  • Norwesco

    SKU: N-64448

    Norwesco 18 Inch Lid with Vent

    $66.29
    The item has been added
  • Snyder Industries

    SKU: SII-34300018

    24" Snyder Septic Tank Manway

    $70.00
    The item has been added
  • Norwesco

    SKU: N-64410

    Norwesco 6 Inch Riser For 10k Underground Tank

    MSRP: $140.00
    $128.33
    The item has been added
  • Norwesco

    SKU: N-63514

    Norwesco 20 Inch Manhole Extension - 6 Inch Tall

    $130.02
    The item has been added
  • Snyder Industries

    SKU: SII-5160000W94201

    Snyder Industries Septic Cistern Riser 12

    $130.02
    The item has been added
  • Snyder Industries

    SKU: SII-RISER12

    Snyder Industries 12 Inch Riser (12 Inch H x 20 Inch D)

    $132.02
    The item has been added
  • Norwesco

    SKU: N-63832

    Norwesco 6 Inch Manhole Extension

    $140.02
    The item has been added