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Do you have questions about BSF?

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Emilie SanmartinCAWST
Senior Program Manager, Global Services - CAWST

Are you training biosand filter technicians?

Did you know that you can access all of CAWST's training materials for free? This includes our lesson plans, manuals, factsheets, presentations, agendas and more! You can find the resources for every workshop we deliver, free and online.

If you have a team making and installing filters, download our workshop materials for biosand filter technicians to teach them how. We really like the following video series to help train biosand filter technicians.

Need help tailoring our training to better meet your needs? We can help you, just contact us at or reply to this email.

Are you feeling intimidated about training others? CAWST can support you to do that too. Check out our training calendar for upcoming dates of our workshops on Delivering Effective WASH Training and Creating Effective WASH Training. 

Don't see any dates in your region? Contact us and we can work to set up something in your region - or provide remote support. 

Emilie SanmartinCAWST
Senior Program Manager, Global Services - CAWST

Let the water Flow! (through the sand)

Installing a biosand filter is one of the most exciting parts of implementation! You get to see all your hard work come together and test your final product.

We have two videos to share with you on how to properly install biosand filters:

What was your flow rate? Did you get it exactly right? Or do you need some help to figure out how to get it right? We are here to help!

Emilie SanmartinCAWST
Senior Program Manager, Global Services - CAWST

How do you clean sand?

How do you know if your filtration sand is clean enough? 

It might seem a bit odd to wash sand, but it is one of the most important things you do when building a biosand filter. Don't forget to also wash your gravel! Selecting the best available sand, sieving it to get the right size grains, and washing your sand and gravel properly will minimize the turbidity and contamination of the filtered water.

Here are some resources to support you with this process:

Emilie SanmartinCAWST
Senior Program Manager, Global Services - CAWST

Cracked or crumbling concrete!?

If you have started making concrete filter containers, you'll have discovered that it can be tricky. How well you prepare the concrete, pour the filter, and remove the filter from the mold impacts the quality. The higher quality you make your containers, the longer your filters will last!

Check out the resources below for guidance on building a high quality filter container. Following these instructions will go a long way in avoiding crumbling and cracked filter bodies, and lost time and money building new containers.