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6 Person Marsh ENCO Sewage Treatment Plant (Gravity)

Regular price
£1,650.00 (£1,375.00 ex VAT)
Regular price
Sale price
£1,650.00 (£1,375.00 ex VAT)
Est. delivery: 5-7 working days

This sewage treatment plant comes with a gravity outlet and is suitable for dwellings with up to 6 people or a 4 bedroom house. The Marsh ENCO range offers a cost-effective solution to sewage treatment, making this product budget-friendly

Marsh sewage treatment plants are widely regarded as the most efficient, reliable and economical domestic systems on the market.

This product is tested to BSEN12566:3 and CE-marked which makes it compliant with the latest Building Regulations requirements, as well as environmental standards. It has a class-leading effluent quality of 11.5:19.2:8.4 (BOD:SS:NH4) ensures discharges well within national consent standards.


  • Near silent, energy efficient compressors - low cost of running & maintenance
  • Three chamber system for separation and retention of solids improves final effluent quality
  • Standard or shallow options enable suitability for all site conditions (including driveways - subject to plinth/surround to prevent superimposed loadings)
  • High specification bio-media (310m3 per m2 ) and membrane diffusers ensure even circulation to eliminate 'dead spots'
  • Internal recirculation (from final to primary chamber) continues treatment process to provide higher effluent quality whilst balancing flow over 24 hour period or periods of intermittent use
  • Integral lifting eyes for improved on-site handling
  • Unique 'keying-in' lip to assist anchoring into granular or concrete surround


Rest assured that our Marsh sewage treatment plants come with a 10-year structural warranty and have a 50-year design life.

Installation Service:

If required, we can also provide you with an installation service at an additional cost (location dependent). Contact us on 0121 351 3230 to find out more.

View product data sheet here.

Image for illustrative purposes only. The ENCO is grey in colour.

Full Description

This sewage treatment plant is for dwellings with up to 6 people or 4 bedroom house. It comes with a gravity outlet.

Why choose Marsh ENCO Sewage Treatment Plant?

If your property is unable to connect to the mains sewerage infrastructure, your most cost-effective and environmentally friendly “off mains” option is a packaged sewage treatment plant. Take advantage of the new ENCO range from Marsh Industries; it offers a budget-friendly solution to off0mains sewage treatment systems.

In basic terms, a sewage treatment plant is a below-ground tank which treats the incoming effluent to an environmentally acceptable quality. This treated water can then be legally discharged to flowing surface waters or in-ground soakaway following applicable exemptions or consents.

The Marsh ENCO Sewage Treatment Plant is an excellent choice. Notwithstanding the anaerobic absorption occurring in the essential settlement tank (as septic tanks) the ENCO unit permits the cleared up water to go into a second “air circulation” chamber where it is dealt with to expel the broken up constituents. Here oxygen-consuming microscopic organisms, upheld by diffused air and versatile media, guarantee full treatment is accomplished before the treated emanating (and ‘sloughed off’ microscopic organisms) stream to the last settlement chamber before release.

This Marsh ENCO plant treats effluent to British and European Standards to allow it to be clean enough to be discharged back into the watercourse whilst reaching national consent standards. Our tanks can be manufactured with either a gravity or pumped outlet to meet your site requirements.

Our ENCO domestic sewage treatment plant comes with lifting eyes to make unloading and installation faster and safer. They have also been designed to self-level on the base and use unique pipe connections to ensure the installation is undertaken efficiently and correctly.

What are the benefits of the Marsh ENCO Sewage Treatment Plant?

We find our customers like the ENCO range due to its ease of installation, reliability, and cost-effective operation and maintenance.

• No moving parts
• Low running and maintenance costs
• Faster and safer to install due to lifting eye
• Tested and certified to BSEN12566-3
• 50-year design life
• 10-year structural guarantee

Our sewage treatment plant installation service

If required, we can also provide a complete package where we will supply and install your sewage treatment plant at an additional cost. Our installation service is dependent on your location. Contact our team of specialists on 0121 351 3230 to find out more.

Technical Specification

No. of people: 6

Height (mm): 1935mm

Outlet: Gravity

Outlet Invert: 625mm

Inlet Invert: 550mm

Width (mm): 1650mm

Length (mm): 2602mm

Outlet Type: Gravity

Installation Service

We can also offer an installation service for our stormwater attenuation, rainwater harvesting, water storage and sewage treatment solutions. Get in touch here.

Contact Us

Our team of experts are available and ready to speak to you. You can contact us or call us directly on 0121 351 3230. Available Mon-Friday 8am-5pm.

Further questions?

Our team of specialists are here to help. We install many of our products so can provide real-world advice. We also offer a free take-off service if required.

Make an enquiry

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