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The BIOROCK is designed to biologically purify pre-settled domestic wastewater, free of oils and greases. It is a modular

Conception and operates in a unique way that eliminates the need for electricity to power the treatment process.

The BIOROCK is the most sustainable Sewage Treatment Unit available as the whole treatment process operates under

Gravity and should electricity be required for the outlet it can be done via solar power. If however mains electricity is used to

Pump the treated effluent a year it cost around 75p per person per year.

As a result of its simple operation a 5 person BIOROCK ™ will save you approximately £400 per year

Every year on running costs compared to the UK market leader. This is a saving of approximately £2000 over 5 years. On larger systems this saving is even greater.

Advantages of BIOROCK

  • No energy consumption for the purification.
  • Can operate using NO electricity if required.
  • Long emptying interval.
  • No internal moving parts.
  • Lowest running costs of any system.
  • Smallest carbon footprint of any system.
  • Best effluent quality of any UK system.
  • Ability to handle absence periods (holidays).
  • Fast start-up period (1 day).
  • Ability to handle intermittent loadings (peak and
  • Low flows) i.e. holiday homes.
  • Compact and underground installation.
  • Low visual footprint.
  • Easy to install.
  • Minimum maintenance.
  • Odor and noise free.
  • Official Certificate of EN 12566-3.
  • Due to its modular construction populations of.
  • Up to 250 can be catered for.


BIOROCK® – How It Works

Bacteria grow in the fibre and digest the organic material as it trickles through. Instead of using electricity-guzzling Compressors to provide the air, the BIOROCK bio-filter utilizes the wind and natural ‘chimney-draft’ to pull the air through the

Plant with no electricity required.

The natural fibre works with nature, not against it and is self-cleaning. These are the bags that can be seen when you open the lid on the plant and are generally yellow.

The pre-filter tank is included in the sewage treatment package. This tank goes in front of the Biorock, and is called the settlement tank.

EN 12566-3

The BIOROCK treats wastewater in the way nature intended. In nature sewage is broken down in the air and the soil not in water this is because oxygen is the key requirement for aerobic digestion and there can only ever be a limited amount of oxygen in water.

The BIOROCK is a dual tank Sewage Treatment Plant – Settlement Tank followed by the BIOROCK Filter.

The raw sewage first enters the settlement tank which separates the solids from the liquid part of the effluent. This pre-filter digests most of the solids anaerobically and only requires emptying every 3 to 4 years.

The Primary Effluent then enters the BIOROCK bio-filter which uses layers of natural fibre material in contact with air to treat the effluent in exactly

The same way as Nature treats effluent in the soil or on the margins of a pond.

BIOROCK® – Installation Options

Gravity For sites on a slope no electricity is required at all as the outlet can be run straight to your soak-away or water Course.

Standard Pump For most sites not on a slope a pump will be required to raise the treated effluent to within 500mm below ground level. From here the treated effluent will run under gravity to your soak-away or water Course.

This pump is the only electrical component and costs about 75p per person per year to run. Bear in mind A separate pumping chamber is required for this and another inspection cover will be seen at ground level.

Solar Powered PumpWhere it is difficult or costly to run electricity to the BIOROCK a solar powered pump can be provided.

Like all sewage treatment units, the system requires regular servicing. This is a Condition of your E.A. Consent to Discharge.

The BIOROCK comes with a 25yr tank guarantee which is also only valid if the unit is serviced as per the manufacturers’.Installed and maintained by qualified certificate Biorock Engineers.

Typical de-sludge intervals are 3 to 4 years. Service agreements are available through Keens. Keep our Streams and rivers safe for our children. NEVER allow unqualified persons to tamper with your unit.The BIOROCK operates in a unique way and although it is easy to install it must be done or overseen by trained personnel who understand the system.


Call us today to discuss your requirements on

01202 82 80 81



Blocked drain clearance, C.C.T.V surveys, treatment plant installations, soak-aways, septic tanks, throughout Dorset, Hampshire, and Wiltshire



Keens Drainage installing a Biorock in the New Forest