SBS™ - Small Bore Sewer™

The Clearford Clarifier

The SBS™ system is comprised of an individualized primary treatment facility – a clarifier tank – located on each property, that separates solids and liquid components of sewage, and contains and directs a predominantly solids-free liquid effluent by gravity through small diameter pipes to the final treatment plant. Natural digestion within the individual clarifiers takes place during the residency period of every seven to ten years; during this seven to ten year design clean-out cycle, sludge accumulation rate naturally decreases in annual volume. Sludge removed from the clarifier tank is more homogeneous and more economical to treat, once it has digested anaerobically.

Although similar in appearance to a standard septic tank, the design of the Clearford clarifier is significantly different. High strength concrete is used to build the vacuum tested and pre-plumbed tanks at the factory to guarantee a watertight vessel. The tank inlet and outlet are embedded into the tank at the factory, and all hatches are sealed prior to testing and delivery. The weight of the SBS™ tank is more than similar concrete vessels with the same outside dimensions.

Primary treatment (solids settling) occurs within the first chamber. The SBS™ clarifier’s internal plumbing is specifically designed to reduce the amount of suspended solids in the fluid without the use of effluent filters. The clarifier reduces total suspended solids to approximately 35 mg/l from the 200 mg/l found with historic sanitary sewage. The SBS™ clarifier has been utilized in residential, commercial and industrial applications.

HPDE (high density polyethylene)

The patented Clearford sewer system utilizes fused-joint HDPE (high density polyethylene) piping for its collection mains, laterals and clean-out access points. This pipe is stronger, more resilient, and more flexible than conventional polyvinyl chloride (PVC) sewer pipe. HDPE pipe system has a design life of 90 years, compared to the 35 year life expectancy of historic PVC materials. This strong, resilient material requires minimal bedding, offering a more flexible range of layout possibilities. The system is not as alignment sensitive as historic sewer solutions and can be designed for boulevard as well as in rear lot areas. All connections, bends and appurtenances are butt-fused (welded) on-site to create a sealed, leak-free piping system that completely eliminates groundwater infiltration into the sewer system and the potential for sewage leaching into the environment.  HDPE pipe can be supplied in 350 M rolls and can be efficiently installed through various laying procedures.

Trenchless Technology

The use of HDPE materials permits utilization of (no-dig) trenchless technology (TT) for installing mains and laterals. The use of trenchless technology minimizes surface and subsurface disruption during construction. TT minimizes the impact on the environment by preserving surface and subsurface materials.  In many cases, environmental construction considerations such as silt screens, dewatering containment and clay trench seals can be eliminated when the lines are installed using horizontal directional drilling (HDD).

Clean-Out Access Holes

SBS™ maintenance clean-outs are vertical extensions of the HDPE sewer main system (usually 75 mm in diameter) and are designed along the sewer routing for future access for flushing the piping system. Entry to the main system (for flushing) is through these vertical stacks, requiring the removal of the HDPE cap to provide hose access. The clean-out housing is constructed with high-grade, durable HDPE ribbed culvert materials, and a secured cast iron bolt-on lid. The maintenance holes can be installed on or off the roads, in the grass boulevard and along the service corridors. Surface access to the main system is readily available for the designed-in 7 year maintenance flushing. The main system requires flushing every
seven years through strategically designed
clean-outs/flush points, in contrast to standard
maintenance requirements of historic sewers.