For partnersIndustry insightsFor investors

Water and technologies · 4 min read

Water at a car wash. Osmosis, recovery and retention explained clearly.

Final rinse water, reverse osmosis reject water and wastewater from the bays have different properties. See how to organise the water cycle and discuss savings based on measurements.

TIXEPrepared by: TIXEUpdated:
WATER PERFECT CLEAN — illustration of the water preparation system
WATER PERFECT CLEAN.
3water streams to distinguishRO reject water, process wastewater and rainwater require separate decisions.
2questions before recoveryWhere does the water come from, and what will it be reused for?
1common measurement periodMeter readings, car wash activity and costs are compared over the same days.

What this guide covers

Three different water streams, the roles of TIXE technologies and a list of data needed before changing the installation.

First identify the water you want to use.

“Water recovery” can refer to different installations. Before selecting equipment, draw a simple map: source, tank, treatment and point of use. This makes it easier to assess what actually returns to use and what is only stored temporarily.

01

Reverse osmosis reject water

Produced when water is treated through RO membranes. It is separate from water running off a washed vehicle. Any further use must be selected according to water quality and site requirements.

02

Process wastewater

Runs off the bays carrying dirt and cleaning product residues. Reuse requires a treatment system suited to this water stream and identification of the programmes to which the water can return.

03

Rainwater

Comes from precipitation. Retention means storing it; using it in an installation is a separate task. The collection area, treatment method and intended use must be established.

Treatment prepares water for a specific task.

In the TIXE range, WATER PERFECT CLEAN combines filtration, softening and reverse osmosis. These stages address different water characteristics: preparing it for the system, compatibility with chemicals and final rinsing to reduce mineral marks.

  1. Incoming waterIdentifying parameters and installation requirements.
  2. PreparationFiltration and softening according to the configuration.
  3. Reverse osmosisPreparing water for the final rinse; reject water is also produced.
  4. Appropriate point of useA wash programme or a separately selected auxiliary application.

The diagram shows the role of each stage, not the hydraulic design of a specific car wash. Do not determine osmosis operating ratios solely from tank capacity. Prepare water test results, equipment model and production and reject readings, where available, for your discussion with a technician.

AQUARIUS and CYCLO-BOOSTER have different roles.

AQUARIUS — illustration of the reverse osmosis reject water reuse system
AQUARIUS · use of RO reject water.
SolutionWhere does the water come from?What is it for?
AQUARIUSReject water from reverse osmosis.Reuse for auxiliary applications, such as cleaning the site.
CYCLO-BOOSTERProcess wastewater from the car wash.Treatment and preparation of recovered water for reuse.

AQUARIUS enables use of a specific water stream generated by reverse osmosis. CYCLO-BOOSTER concerns a different water cycle and is presented by TIXE as a completed project being prepared for implementation. Suitability and the scope of integration are agreed for each site.

When comparing solutions, ask about outlet water quality, permitted uses, maintenance, consumables and space requirements. The number of litres recovered by a device alone does not describe the car wash's full water balance.

Calculate savings at the boundary of the whole site.

Establish which result you want to improve: fresh water intake, wastewater discharge volume, cost or installation availability. Each indicator answers a different question. Operational assessment also requires data on car wash activity.

Water consumption indicator

Fresh water intake during the period ÷ number of recorded washes in the same period.

If the system does not reliably count visits, do not treat every payment as a separate vehicle. You can compare consumption with programme operating time, stating how the indicator is constructed. Add cleaning, winter protection, equipment flushing and unusual events.

Include the energy, servicing and materials needed to operate the additional system in the costs. A method for comparing periods is provided in the operating costs guide.

Prepare the data before choosing a solution.

The EPA WaterSense guide emphasises leak control and matching treatment to the intended use. It also does not recommend routinely retrofitting self-service car washes with wastewater recovery, citing risks including contaminants introduced into the bays. This is an important reason to design such a solution individually and check its operating conditions.

CYCLO-BOOSTER in a stainless steel housing — rendering
CYCLO-BOOSTER · project being prepared for implementation.

With this information prepared, the discussion can focus on your site: water quantity and quality, available space, maintenance and expected results. The scope of further measurements and the sequence of works can then be agreed.

FAQ

Frequently asked questions

Is reverse osmosis reject water the same as wastewater from washing cars?

No. Reject water is produced during water preparation in the RO system, while process wastewater flows from the bays. AQUARIUS and CYCLO-BOOSTER therefore serve different purposes.

Is recovery always worthwhile at an existing car wash?

It requires an individual assessment of water quantity and quality, space, integration and maintenance costs. First establish the current water balance and resolve confirmed irregularities.

Can rainwater be used directly in every programme?

Its application must match its quality and the installation requirements. Retention alone does not prepare water for the final rinse or replace a water treatment design.

Sources and materials

Prepared by TIXE. EPA is a source of general water management principles and retrofit limitations; it does not assess or recommend TIXE products. The diagrams in this guide explain the process and do not replace an installation design.

Prepared: 13 October 2026. Photos and illustrations from TIXE materials.

Your next step

Let's start with the water cycle in your car wash.

Send a description of the installation and the goal you want to achieve. We will establish which data and solutions are worth considering.

Discuss water management See the other guides

PRIVACY SETTINGS

Google map. Your choice.

You can find the directions map to the TIXE factory on the Contact page. You can use the entire website without enabling it.

Essential functions

Remembering selected settings. No analytics or advertising.

Always active
Show Google map

Only after you enable it will we connect to Google, which will receive connection data and may use cookies. Google policy ↗

You can change your choice in the footer at any time. Disabling the map stops it from loading, but does not delete data previously shared with Google.

TIXE privacy policy