Secure Effluent Storage for Pump-Out Wastewater Systems

What do you do with septic effluent when the property can't rely on an evapo-transpiration field? RELN holding tanks provide dedicated storage for effluent overflowing from a septic tank, retaining it until pump-out by an effluent tanker. Explore the broader RELN range when planning wastewater infrastructure for rural, remote & unsewered Australian properties.

Choosing the right tank starts below ground, not with capacity alone. Inlet depth, site conditions, required storage, excavation depth, pump-out access & local requirements all influence the configuration. RELN offers standard plus deep-invert holding-tank options, giving installers greater flexibility where wastewater pipe levels differ between sites.

Everything upstream influences what eventually reaches the holding system. Where domestic kitchen wastewater feeds into septic infrastructure, RELN | Grease Traps can help intercept fats & oils before they travel further through the wastewater system.

What Are RELN | Holding Tanks?

RELN holding tanks are purpose-designed collection wells or pump-out tanks for storing septic effluent when on-site field disposal isn't suitable. Instead of sending the effluent into an evapo-transpiration field, the holding tank retains it for later removal by an effluent tanker.

Depending on the selected configuration, features can include:

► 3200L holding capacity
► Standard holding-tank configurations
► Deep-invert holding-tank configurations
► Undrilled base options
► Reinforcing structural ring configurations
► Riser on the deep-invert model
► Lid & manhole components
► Inspection components on applicable models
► Accessory packs on selected configurations
► UV-protected lid & manhole cover
► Unique stepped ribbing for additional strength
► Lightweight construction for easier transport & installation
► 15-year RELN manufacturer warranty

Configuration matters because RELN doesn't package every 3200L tank identically. Product options include undrilled tanks plus reinforced configurations, while the 3200L Deep Invert Holding Tank includes an undrilled base, reinforcing ring, riser, lid, accessory pack without outlet, manhole cover & lid.

Where surrounding property works also involve dedicated drainage infrastructure, RELN | Drainage & Pits can support separate surface-water management requirements.

Why Choose RELN | Holding Tanks?

Some properties need wastewater storage rather than another downstream disposal field. Holding tanks address that requirement by providing a controlled collection point where septic effluent can remain until scheduled removal.

RELN holding tanks can suit projects requiring:

► Septic-effluent storage
► Pump-out wastewater arrangements
► Rural wastewater infrastructure
► Remote-property wastewater management
► 3200L capacity options
► Deep-invert installation capability
► Accessible tanker pump-out
► Australian Standards-approved tank systems
► UV-protected access components
► Structural features designed for buried installations

Strength becomes a serious consideration once several tonnes of surrounding ground are involved. RELN uses unique stepped ribs for additional strength, while applicable configurations incorporate a reinforced structural brace ring designed to help prevent crushing.

Major installations also involve excavation, access preparation plus coordination between trades, making Commercial Construction a relevant supporting range for broader site work.

Common Applications

A holding tank becomes particularly valuable when the wastewater plan says “collect & pump out” rather than “disperse on site”. That can occur across several Australian property & construction settings.

► Rural homes – provide dedicated effluent storage beyond reticulated sewer networks.
► Remote residences – form part of an approved pump-out wastewater arrangement.
► Properties without suitable field disposal – retain septic overflow where an evapo-transpiration field isn't appropriate.
► Pump-out systems – hold effluent until scheduled tanker collection.
► Regional building projects – support approved wastewater infrastructure where conventional sewer connections aren't available.
► Replacement systems – replace an existing compatible holding tank where continued pump-out storage is required.
► Deep-invert installations – accommodate projects where incoming wastewater pipework needs greater burial depth.
► Challenging sites – provide dedicated storage where the approved design accounts for ground conditions, excavation plus future tanker access.

The smartest location works for the excavator today & the pump-out operator years from now. Construction access, manhole position, hose reach, gates, landscaping plus driveway conditions should all be considered before the tank disappears underground.

For moving site equipment, materials or components during substantial installation work, Material Handling Equipment can support broader site logistics.

Product Selection Guide

Start With the Approved Wastewater Design

Which tank does the site require rather than simply have room for? Establish that answer before choosing a configuration.

Check:

► Required holding capacity
► Local council requirements
► Approved wastewater design
► Septic-tank arrangement
► Expected effluent flow
► Pump-out requirements
► Inlet depth
► Ground conditions
► Installation location
► Tanker access

Council requirements deserve attention before a tank is purchased. RELN recommends contacting the relevant local council to establish specific tank-capacity requirements for the property.

Compare Standard & Deep-Invert Holding Tanks

Incoming pipe depth can quickly separate a standard installation from a deep-invert one.

Extra depth requires the correct tank rather than an improvised modification. RELN states that deep-invert holding tanks are supplied with a factory-installed reinforced structural brace ring plus a riser arrangement intended for the deeper installation.

Holding Tank vs Septic Tank

They may sit within the same wastewater system, but their jobs aren't interchangeable.

That distinction can prevent an expensive ordering error. Choose a holding tank where the approved system specifically requires effluent storage for pump-out rather than assuming it performs the treatment role of a septic tank.

Compare RELN 3200L Holding Tank Configurations

Two tanks with the same nominal capacity can arrive with very different components.

Product-code matching is far safer than ordering by capacity alone. Confirm the required openings, reinforcing components, riser arrangement, inspection access plus supplied accessories against the installation plan.

Check Physical Dimensions Before Excavation

Discovering the excavation is undersized after delivery is an avoidable problem. RELN lists its 3200L reinforced holding-tank configuration at approximately 2038mm deep plus 1998mm in diameter, while the deep-invert version reaches approximately 2410mm in depth.

Planning should consider:

► Exact model dimensions
► Excavation depth
► Tank diameter
► Inlet position
► Working clearance
► Ground conditions
► Installation access
► Manhole position
► Backfilling requirements

Different configurations can change the hole you need to prepare. Work from the current documentation for the exact model rather than carrying dimensions across from another RELN tank.

Accurate positions, levels plus clearances can be established with suitable Measuring & Layout Tools during site preparation.

Plan the Pump-Out Route Before Installation

Can an effluent tanker realistically service the tank after fences, landscaping & buildings are finished?

Consider:

► Tanker access
► Hose reach
► Manhole accessibility
► Gates
► Driveway conditions
► Turning space
► Buildings
► Fencing
► Landscaping
► Wet-weather access

Serviceability is a long-term requirement rather than an installation-day detail. Protect the route needed for inspection plus pump-out from permanent obstructions wherever the approved site plan allows.

Understand the Half-Capacity Requirement

One operating detail is particularly important: RELN says its holding tanks must be maintained at half capacity to prevent flotation.

That means:

► Pump-out procedures matter
► The tank shouldn't routinely be completely emptied
► Service providers should know the tank requirements
► Manhole access needs to remain practical
► Tank condition should be monitored
► Manufacturer instructions should remain available

Make this requirement part of the property's service information. Anyone arranging future pump-outs should know the system is a RELN holding tank plus understand the manufacturer's half-capacity instruction.

Consider Ground Conditions

Buried tanks live with whatever the site throws at them year after year. Groundwater, soil characteristics, excavation stability plus surrounding drainage all deserve professional assessment.

Installation planning may need to address:

► Soil conditions
► Groundwater
► Excavation stability
► Backfill
► Surface-water movement
► Nearby vehicle loads
► Existing underground services
► Required setbacks

Site-specific conditions should drive site-specific decisions. Follow the current RELN installation guide, approved wastewater design plus applicable plumbing & local authority requirements rather than relying on general installation assumptions.

Keep Stormwater Separate

Rainwater rushing across the property has a completely different job from septic effluent stored underground. Surface-water drainage should be planned independently so stormwater isn't confused with the blackwater system.

This distinction is particularly important around:

► Roof runoff
► Driveways
► Paths
► Hardstand areas
► Yard drainage
► Surface pits
► Channel drainage

Keeping those systems conceptually separate makes maintenance easier too. A holding tank is for effluent storage, not a substitute for stormwater collection or surface drainage.

Protect Access After the Landscaping Is Finished

A beautifully landscaped yard isn't much help if nobody can find the manhole at pump-out time.

After installation:

► Record the tank location
► Photograph access points
► Keep the manhole reachable
► Avoid permanent structures above service points
► Preserve tanker access
► Retain approved plans
► Keep product information with property records

Future owners may know nothing about the installation beneath their feet. Clear records can make inspection, servicing plus eventual property handover considerably easier.

Coordinate Delivery & Installation

A 3200L underground tank deserves more planning than simply choosing a delivery date. Confirm site access, excavation timing, installer availability plus handling arrangements before the tank arrives.

Preparation can include:

► Checking delivery access
► Clearing the work area
► Identifying underground services
► Preparing excavation access
► Confirming handling requirements
► Protecting components on site
► Coordinating plumbing work
► Keeping unauthorised people clear of excavation

Appropriate Safety & PPE should be selected around excavation, construction work plus the hazards present on the individual site.

Expert Tips

► Get the site requirement first. Capacity, configuration plus installation details should follow the approved wastewater plan.
► Confirm council requirements before ordering. Tank-capacity requirements can vary by location.
► Check the inlet depth early. It can determine whether a standard or deep-invert configuration is appropriate.
► Match the product code, not just “3200L”. RELN offers several holding-tank configurations with different supplied components.
► Keep the half-capacity instruction with the service records. Future pump-out operators need to understand it.
► Measure the exact tank configuration. Standard plus deep-invert models differ in overall depth.
► Give the tanker a future route. Gates, sheds plus landscaping shouldn't accidentally block servicing.
► Record the manhole location. Photos plus measurements are inexpensive insurance against future searching.
► Don't combine wastewater plus stormwater roles. Each system should perform the job it was designed for.
► Check the support structure on deep-invert models. RELN requires the appropriate factory-fitted reinforced brace ring when using its riser arrangement.
► Protect components before they go underground. Lids, accessory packs plus fittings are easier to inspect before installation.
► Coordinate excavation plus plumbing schedules. A tank sitting beside an unfinished excavation helps nobody.
► Keep current instructions on site. The exact RELN model documentation should guide installation rather than assumptions from a previous job.