Splash works to ensure that all children around the world have access to safe water, clean hands, and child-friendly toilets.  Ensuring access to safe water means that we purify the drinking water and improve water availability at every partner site that lacks access to safe water.  Fundamental to our mission is the purification of water for purposes of consumption by our beneficiaries at our partner sites.  We purify water by installing and maintaining a water purification system that is designed according to the water chemistry at the site and the number of beneficiaries there.  We improve water availability by increasing water storage capacity, expanding water sources, fixing leaks, and advocating to the municipal authorities to increase water supply to our partner sites.  We ensure access by installing drinking water stations and taps specifically designed for children in urban institutions.  Finally, we are committed to the ongoing functionality of the drinking water infrastructure that we install. We thereby commit to regular water quality testing and ongoing maintenance of our systems either by Splash staff or a verified professional 3rd party service provider.

WHAT THE STANDARD IS: Drinking water implementations always include the following categories: water storage tanks, water purification systems, drinking water stations, and all of the related components that go along with each of the above categories (taps, piping, pumps, etc.).

This standard will cover how the infrastructure team plans, designs, and installs the drinking water related infrastructure for Splash implementations.  There are other standards specifically for handwashing stations, water storage, and drinking water quality testing.

Planning and Design:

Following a Pre-Implementation Survey and Technical Site Visit, the local WASH Infrastructure team will begin the design and planning for the implementation of the drinking water infrastructure.  The design and planning phase is centered largely around Splash’s target ratios.

Much like the standard for the Water Purification System Selection Process, the first step is regarding water quality.  Based on the Pre-Implementation water quality test results, the local WASH Infrastructure Lead with consultation from the global WASH Infrastructure Manager, will determine if additional pre-filtration treatment is needed to be installed.  Pre-filtration is typically only necessary when the primary water source of the site is groundwater (either on-site or city-supply wells), and it has certain molecularly small water quality parameters (like heavy metal ions, nitrate, and others) that Splash’s Antunes filter system (VZN) is not designed to remove.  If pre-filtration is required, then the local and global WASH Infrastructure leads will work together to design the optimal pre-filtration system in terms of components, volumes, and treatment process layout.  The global WASH Infrastructure Lead should always be consulted if pre-filtration is necessary, or if there are any abnormal results from the Pre-Implementation water quality test.  More details regarding the water quality testing schedule and methods can be found in the Drinking Water Quality Testing Standard.

Once the decision is made on whether or not pre-filtration is needed, the next planning step for the purification systems is to determine how many purification systems are necessary at the particular site.

This decision is based on the two following standards:

• a drinking tap to student ratio of 1:75 (more details are in the next section on drinking stations), and
• a minimum flowrate of 3 L/min at one drinking tap when all drinking taps are on simultaneously.

These standards are then used in conjunction with the maximum flowrate of the purification systems available that have gone through the process outlined in the Water Purification System Selection Process Standard.  The local WASH Infrastructure Lead will then use the standard ratios, the max. flowrate, and the largest single shift population at a site to determine how many water purification systems need to be installed at the site.

• For example, if we have a school site with a total daytime population (students + staff) of 1,100, and a night school population of 500, then we would select 1,100 as our largest single shift.  As always for the storage, drinking tap, and handwashing tap ratios, we include both students and staff in the population numbers.  
• Next, we would determine the number of drinking taps that need to be installed at the site.  Based on the ratio listed above, we would need to divide 1,100 by 75.  This yields 14.6, we round up to the nearest whole number to get 15.
• Since Splash stations provide drinking taps in multiples of 2, we would then round up to the nearest multiple of 2.
• So, in the end, the 14.6 taps becomes 16 taps.  
• We then multiply 16 taps by the minimum flowrate of 3 L/min to determine that we need a purification system with a maximum flowrate of at least 48 L/min in order to supply all 16 taps with 3 L/min simultaneously.  One of the most installed Splash purification systems is the Antunes VZN 441V.  It has a maximum flowrate of 57 L/min.  A single VZN 441V would be more than enough to meet the drinking water needs of this school site.

Based on the above calculations and logic, a VZN-441V filter system can serve up to 18 drinking taps simultaneously (equivalent to 9 Splash drinking stations and a maximum single largest shift population of 1,350 students and staff).  A UF-216cc can serve up to 2 drinking taps simultaneously (equivalent to 1 Splash drinking station and a maximum single largest shift population of 150 students and staff). Any campus with a single largest shift population (number of simultaneous users) over 1,350 students and staff, will need more than one VZN-441V installed. All of the above numbers are based on the manufacturers' listed maximum flowrates that are often calculated in ideal conditions. If actual conditions do not allow for a high enough flowrate to serve the maximum number of taps, then the local WASH Infrastructure Lead must consult with the global WASH Infrastructure lead to determine the best solution.  Solutions could include installing an additional filtration system, larger diameter pipes, or more powerful booster pumps.

Additional purification systems may be necessary at campuses that have very spread out buildings, or other physical site challenges.  The local WASH Infrastructure lead will need to inform the global WASH Infrastructure lead when these instances arise.

If a campus has physically separated grades or groups of students (such as a separate kindergarten area), then the above ratio and infrastructure calculations need to be applied to each physically separate group of students and staff on that campus separately.  

If more than a single purification system is required at a site, then two of the same type of system should be installed.  Two different filtration systems should never be installed at the same site.  An exception could be made for rare instances.  If this is the case, then the local WASH Infrastructure Lead should contact the global WASH Infrastructure Lead before installation.

After the number and type of purification systems have been calculated, the local WASH Infrastructure Lead would consult with the site’s management to determine the best location to install the purification system.  Some guidelines for ideal placement would include:

• out of reach from children,
• close to the water storage tanks or the drinking stations,
• at a higher elevation than the drinking taps whenever possible.

Ultrafiltration (UF) based purification systems (as typically installed by Splash) can be placed inside or outside as long as they are fully protected from weather and vandalism, and as long as the temperature never gets below 4 degrees Celsius. For example, in Kathmandu, UF systems should never be installed outside since temperatures in December and January regularly get below 4 degrees Celsius.  UF systems should also not be placed in direct sunlight. The global WASH Infrastructure Manager should be consulted if a non-UF based purification system is to be installed.

There are many necessary accessory components to Splash’s typical (UF) based purification systems. The required components are the following: two pressure gauges (one before and one after the UF membrane), strainer, booster pump, automatic pump controller, voltage regulator, lockable protective case, backflushing system (programmable timer/controller, valve), and isolation valves for the strainer and for the entire system.

The pressure gauges, strainer, protective case, backflush system, and isolation valves are sometimes included with the UF system from the manufacturer.  Whenever they are not included, the local WASH Infrastructure Lead must procure each of these items locally, and have these items installed with every new UF system.  Again, if a non-UF system is to be installed at a site, the local WASH Infrastructure Manager needs to consult with the global WASH Infrastructure Manager.  It is the local water infrastructure lead's responsibility to ensure that all necessary components are installed properly at each campus.

Valves: Quarter turn ball valves are always preferred over multi-turn compression globe valves in any plumbing that Splash does (storage tanks, purification systems, stations, sanitation, or any other plumbing).  There should be at least one valve between the water storage tank and the pump, another valve between the pump and the strainer, another valve between the strainer and the UF membrane, and a final valve between the end of the purification system and the drinking stations.  Additional valves between each Splash drinking station are optional.  It is up to the discretion of the local WASH Infrastructure team to install additional valves wherever needed.

Booster Pumps and Pump Controllers: Booster pumps come in a variety of sizes (by horsepower) and should be sized based on the number of taps that they need to push water to.  For 2 - 8 taps, a 0.5 hp pump should be used.  For 9 - 12 taps, a 1 hp pump should be used.  For 13 - 18 taps, a 1.5 hp pump should be used.  For sites where over 18 taps need to be served, then multiple systems with multiple pumps should be installed.  If over 30 m of pipe is required between the purification system and the furthest drinking tap, then the next size up pump should be installed to overcome the frictional head losses from the length of pipe.  All booster pumps should be fully protected from weather, vandalism, and voltage spikes/drops.  An automatic pump controller should be installed directly above (downstream) the booster pump.

Pressure Gauges: There should always be a pair of pressure gauges installed along with the UF system.  These gauges are used to determine when the UF membrane needs to be replaced.  Please refer to the Scheduled and Preventive Maintenance Standard for more details.  The pressure gauges should always have the same units even if they must be different models of gauges (e.g. both in psi or both in kPa).  Starting in 2020, two pressure gauges are included with every UF system from Antunes.  For all UF systems that do not have two pressure gauges, pressure gauges will need to be installed.

Strainer: A strainer should be installed between the booster pump and the start of the UF system.  While Splash has installed stainless steel mesh strainers in the past, plastic disc strainers have proven to be far more durable, easier to clean, and more widely available than the mesh strainers.  Because of this, disc strainers should be installed on new UF systems whenever the system does not already come with a strainer from the manufacturer.  A widely available, high quality model of strainer is the Azud Modular 100.  Starting in 2020, an Azud Modular 100 strainer is included with every UF system from Antunes.

Voltage Regulator: All electrically powered components of the UF system must be protected from voltage spikes and irregularities through the use of a voltage regulator.  

Electrical: All electrical plugs and outlets must be physically separated and protected from the area of the UF system that has the strainer and carbon filter.  Since those components are often opened to be cleaned or replaced, water easily gets spilled all over the area around those components.  For the safety of all technicians, operators, and the electrical equipment, a dividing wall or raised shelf must be installed to separate the electrical plugs and outlets from getting wet.

Protective Case: UF systems should always be protected with a lockable case.  These cases can be constructed from a variety of materials.  It is preferable if all necessary accessory components can also be housed in one large protective case, even including the booster pump.  The case can include dividing walls and/or shelves to place the accessory components on and to protect electrical equipment from getting wet.  A clear door or access panel on the protective case is optional.  Starting in 2020, a protective metal cabinet is included with every UF system from Antunes.

Backflush System: All UF systems must have a backflush system to allow for the regular internal cleaning of the UF membrane.  All Antunes filter systems come with backflush systems that are pre-built by the manufacturer.  These backflush systems must be connected to an established drainage system.  It is never acceptable to allow the backflush system to drain openly on the surrounding ground.

Fittings: As with every plumbing related work, fittings such as tees, elbows, and bends will need to be installed in and around the UF system.  The system should be installed in such a way and in such a location so as to minimize the number of fittings that need to be installed.  Every fitting causes additional frictional head losses and will decrease the flowrate of the water going towards the drinking stations.

Stickers: A sticker that lists Splash’s local office’s phone number should be put on the side of every installed water purification system.  This way, the partner site cannot lose or forget the phone number to call when our system or any other installed infrastructure requires unforeseen repair or replacement.  Dated stickers or masking tape should be placed on the UF membrane and carbon filter housings to indicate the date of installation and the date of scheduled replacement for each component.

There are a range of other possible optional accessory components for UF systems.  One example is volumetric water meters.  The global WASH Infrastructure Manager should be consulted before volumetric water meters are procured and installed.  While water meters may be required in certain cities in the future, currently Splash does not require them to be a part of every purification system.