We are Elrha, a force for change in the humanitarian community. The research and innovation we support equips the humanitarian community with the knowledge of what works, so people affected by crises get the right help when they need it most.
Our purpose is clear: to empower the humanitarian community to improve humanitarian response. We make this happen by supporting and championing the outcomes of robust research and proven innovations.
We empower the humanitarian community. Find out how we can support you...

What is the humanitarian need?

In emergency situations access to safe water is often disrupted. It is of great importance to provide the affected population with access to safe drinking water to prevent diseases like cholera and diarrhoea from spreading. This requires a method of making water safe that is:

  • easy to use and operate (as there is often limited time or capacity to train each household);
  • affordable;
  • requires no energy or infrastructure;
  • is packable and efficient in transport;
  • will provide at least enough safe water for one family/one year;
  • doesn’t need replacement parts;
  • is robust and light weight, in case of refugee migration situations.

What is the innovative solution?

The Tulip FLOW filter (or FLOW filter), is a portable, gravity operated water purifier that is easy to use and store. It purifies an average of 25 liters of water per hour. Its intuitive backwash function ensures that the filter stays clear and fit for purification and has a fast flow rate. The water filter is based on a micro membrane filtration technology and is an improved model of the existing Tulip Siphon filter, which has a ceramic filter element.

Main features:

  • The FLOW filter will fit into a jerry can, which is the main method of water collection and water storage in households in many low-income countries and in emergency situations.
  • User friendly water filter with an intuitive backwash system.
  • Substantially more affordable as compared to membrane filters with similar filter capacities.
  • Replacement cartridge available and easy to replace (no throw-away system).

What are the expected outcomes?

We will finalise the prototype of the FLOW filter and test it in households in Nepal, Zambia and Ecuador. Based on our findings and feedback, the design will be finalised and the product will be made ready for largescale production.

At the finalisation of the project, we expect to have a water filter that can provide a household of five with safe drinking water for at least three years and is appropriate for (post-) emergency situations due to its affordability, intuitive usability, durability, packability and sustainability.

Latest Updates

Taking water purifiers to the next level

31 Oct 2017

How can we make sure that people in emergency situations have access to safe water in an easy, affordable way? That’s the challenge Basic Water Needs have accepted!


Being the pilot

11 Jan 2018

The bad news is: time flies. The good news is: you’re the pilot


The devil is in the details

24 May 2018

Basic Water Needs test their prototype in the field.


Human-centred design, it makes sense

4 Sept 2018

Basic Water Needs explore the three phases of human-centred design.


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