Individual ecological sanitation

Definition and implications of individual sanitation

Ecological individual sanitation, or non-collective sanitation (NCS), refers to all individual domestic wastewater treatment facilities. It encompasses all the devices and techniques used to collect, treat and dispose of domestic wastewater from isolated households. These fluids include black water (from toilets) and household water (from daily activities such as cooking, bathing, etc.).

Ecological individual sanitation concerns, in particular, homes not connected to the public sewerage system. In France, around 15 to 20% of the population are equipped with an individual sanitation system. This system is particularly widespread in rural areas where the construction of a public sewerage system would be too expensive.

Individual sanitation has many implications and is important from both a health and an environmental point of view. From a health point of view, it aims to prevent the spread of diseases linked to poor wastewater management. Untreated water can contain pathogens that are dangerous to human health. From an environmental point of view, individual ecological sanitation helps to limit pollutant discharges. In doing so, it contributes to the preservation of water resources and the protection of aquatic ecosystems.

The main ecological individual sanitation systems

There are various ecological individual sanitation solutions that you can install in your home.

Phyto-purification system

Phyto-purification is one of the most advantageous autonomous and ecological sanitation systems for wastewater treatment.

Definition and operation

A natural and sustainable sanitation method using plants, phyto-purification allows for depollution thanks to the purifying properties of the roots of specific plants. This is done by integrating a natural marsh. The mechanism of phyto-purification is based on the use of plants such as reeds, which act as a ‘vertical filter’ to purify wastewater.

Once the water enters the system, it is drawn in, filtered and digested by the plants, particularly at the level of the root complex, which is rich in micro-organisms. The ecosystem thus created mainly treats the nitrates, phosphates and metals retained by the water. This eliminates the pollutants present in the water.

The principle of phyto-purification is similar to that of composting. The degradation of pollutants in contact with air produces humus and water vapour. All that is needed for the process to be complete is to allow time for the plants and rushes to colonise each basin.

Aquatiris is the leading French network specialising in phyto-purification. Our ‘Sanitation Garden’ range guarantees you an efficient phyto-purification system: zero tanks, zero emptying, zero foul odours and zero mosquitoes. Our experts will guide you through the entire process, from the planning to the realisation of your project. Whether you are considering an ecological sanitation system for a detached house, a tourist site or an agricultural project, our experienced team can offer you a customised environmentally friendly solution.

Installation of a phyto-purification system

In practice, before installing the two basins necessary for optimal filtration, we start by choosing the right plants. These must have the capacity to absorb the pollutants specific to each stage of filtration. In the first basin, where the main pollutants are retained, the following are planted:

• carex,
• purple loosestrife,
• iris,
• bulrush,
• reeds.

In the second basin, built below the first one, purifying plants such as water mint, iris and purple loosestrife are transplanted. This second basin allows for a more refined purification of the water. Once the cycle is complete, the filtered water is clean and odourless, and can be used to water the garden. The compost collected from the surface of the first treatment basin can also be reused to enrich the soil in flowerbeds and around ornamental trees.

The ecological advantages of a phyto-purification system

Phyto-purification has considerable ecological advantages. This system is an ecological sanitation solution that does not require tanks or the use of large amounts of materials. Macrophyte plants adapt to all types of soil and are resistant to temperature variations and frost. Moreover, although it takes place in the open air, this system does not produce any unpleasant odours. It is also easy to maintain: simple weeding of the basins in spring is sufficient.

A phyto-purification system also does not require fossil fuels to operate and the resulting water can be discharged directly into the environment without risk. It is also an ecological individual sanitation system that does not consume electricity and is based on natural materials.

If you want to avoid installing a septic tank, this solution is a very interesting option. It can perfectly replace traditional septic tanks as it complies with French water treatment regulations. Contact Aquatiris to have your tankless and drainless treatment system installed.

All-water tanks

Unlike the traditional septic tank, which only treats black water, the all-water tank collects and pre-treats all domestic wastewater. Only rainwater does not pass through this ecological septic tank system as it does not need to be decontaminated before use. Currently, this type of tank is the only one authorised by the regulations, given that the installation of septic tanks is now prohibited.

An all-water tank is generally a plastic or concrete tank, equipped with an inlet and outlet circuit. It can be equipped with a:

• sand filter,
• planted filter (reed filter),
• filtering bed.

The device is designed to be watertight, thus preventing the infiltration of wastewater into the soil. The tank must be resistant to pressure and corrosion in accordance with the mandatory EC standard. It is also equipped with ventilation to evacuate potentially harmful fermentation gases. Pre-filters can be added upstream or downstream, and inspection holes are provided for easy access for maintenance, emptying and inspection purposes.

In addition to collecting and retaining domestic wastewater and its pollutants, this individual sanitation system performs several other functions. It liquefies solid matter (accumulation of sludge and grease) to enable it to be treated later in an appropriate way. It also retains solid matter (decanting sludge) and floating matter (grease).

However, this system does have disadvantages. There is a risk of overflowing. Foul odours can also rise to the surface. Plants can also infiltrate the system and block it, which can be difficult to repair.

Micro-treatment plants

The micro-treatment plant is a watertight wastewater treatment facility where the entire treatment process takes place:

• pre-treatment,
• treatment,
• discharge.

It manages the storage, anaerobic degradation (thanks to bacteria) and decantation of suspended matter. It also ensures the retention of sludge, hydrolysis of grease and production of ammonium, all in three separate compartments.

There are two main categories of micro-treatment plants: fixed culture (where the bacteria are fixed to supports) and free culture (where the bacteria are in suspension). In both cases, the filters are pre-treated with specific enzymes to reinforce the development and capacity of the bacteria to effectively decontaminate the water.

Despite their many qualities, micro-treatment plants have one major limitation: they must operate with a permanent power supply. With this individual sanitation system, the treatment cycle must be activated continuously to prevent the bacteria from dying. The micro-treatment plant is therefore not suitable for a secondary home. It also requires frequent emptying due to the rapid accumulation of sludge caused by its compactness.

Dry toilets

Operating by composting, dry toilets are a complement to household water treatment systems in ecological constructions. In this individual sanitation system, urine and faeces fall into a composting chamber where a litter absorbs the liquids and inhibits odours.

To ensure proper functioning, dry toilets often require a forced ventilation system or even a crawl space. In addition, the composting area must be watertight and sized to allow sufficient maturation-hygienisation time.

Even if the process of dry toilets is undeniably ecological, their practical use presents constraints. It requires the addition of sawdust or other plant residues with each use. In addition, emptying must be carried out frequently. There is also the question of the appropriate place to dispose of organic waste, as it cannot be done just anywhere.

The ecological drawback of dry toilets is that they only treat toilet effluents and not other water from sinks and showers. They are therefore mainly ecological for single or occasional use, but are less suitable for the treatment of all water from a dwelling.

How much should I budget for an individual ecological sanitation system?

The price of an individual and ecological natural sanitation system varies according to several criteria:

• the sanitation system,
• the quality,
• the size of the installation.

Individual sanitation with an all-water tank costs between €3,500 and €8,000, while a micro-treatment plant costs between €6,500 and €12,000. If you opt for the installation of dry toilets, the cost varies on average between €1,500 and €3,000. These options may be tempting, but they involve regular and significant maintenance and emptying costs.

At Aquatiris, you can set up your phyto-purification plant at a competitive price of between 11,000 and 16,000. The initial cost may seem high, but it is an ecologically and financially profitable investment in the long term. Once installed, it saves you costly emptying and maintenance costs. Contact us now for a free quote.