Water is the “invisible utility”, whose usage patterns are too often overlooked by companies as a cost of doing business. Water bills can account for as much as 20% of a buildings’ utility cost and upwards in process applications. Compared to other countries, Canadian water prices are well below average. The cost of water is likely to rise as watersheds are depleted, water conservation and efficiency standards are legislated, and municipal governments increase rates to fund repairs to aging infrastructure. To reduce water utility bills, building owners must find ways to limit their consumption without sacrificing occupancy comfort.

2. Water conservation system
Water conservation includes all the policies, strategies and activities made to sustainably manage the
natural resource fresh water, to protect the water environment, and to meet the current and future
human demand. Population, household size, and growth and affluence all affect how much water is
used. Factors such as climate change have increased pressures on natural water resources especially in
manufacturing and agricultural irrigation. Many US cities have already implemented policies aimed at
water conservation, with much success.
Water is the “invisible utility”, whose usage patterns are too often overlooked by companies as a cost of
doing business. Water bills can account for as much as 20% of a buildings’ utility cost and upwards in
process applications. Compared to other countries, Canadian water prices are well below average. The
cost of water is likely to rise as watersheds are depleted, water conservation and efficiency standards
are legislated, and municipal governments increase rates to fund repairs to aging infrastructure. To
reduce water utility bills, building owners must find ways to limit their consumption without sacrificing
occupancy comfort. There are 3 ways to mitigate water utility spending; by reducing use, reusing, and
by collecting
The goals of water conservation efforts include:
 Ensuring availability of water for future generations where the withdrawal of freshwater from
an ecosystem does not exceed its natural replacement rate.
 Energy conservation as water pumping, delivery and wastewater treatment facilities consume a
significant amount of energy. In some regions of the world over 15% of total electricity
consumption is devoted to water management.
 Habitat conservation where minimizing human water use helps to preserve freshwater habitats
for local wildlife and migrating waterfowl, but also water quality
Workflow of Water Conservation System
Low Flow & Waterless Fixtures
Plumbing fixtures (kitchen and bathroom taps, toilets, urinals, and water fountains) account for a large
portion of a buildings water use. We can reduce their water use by replacing existing toilets with
specially designed ‘low-flow’ fixtures (such as dual flush toilets) that will use 50% less water. Traditional
urinal systems have timed cycles that will constantly flush even when they are not used, by integrating
water less or motion controlled units we can eliminate this waste. Sinks can be fitted with tap sets that

3. have electronic sensors which control water flow to timed or motion activated bursts. Shower heads can
be replaced with higher efficiency heads that save water while maintaining high pressure.
Grey-water recycling
It is the process of reusing water from sinks, baths, showers, dish-washing, laundromats, carwashes etc.
is a practice that is becoming more popular as water utility prices increase. Here grey water is collected,
filtered and stored for use as a supply for toilets and landscape irrigation. Black-water (from toilets) is
the only waste water flushed down the drain. There is huge potential for water savings with these
systems, and in larger buildings, they are more cost effective if the system is incorporated in new
construction.
Hydronic Cooling Water Reductions
Larger system components that use water should also be considered for replacement. Older Hydronic
Cooling towers, can account for a large portion of a buildings water utility use. Towers serving old,
inefficient A/C systems can easily use twice the water that a new chiller would need. Also some older
buildings still operate a ‘once-through’ cooling system, which simply flushes water over a cooling coil
and drains the water down the drain. This system costs ten times as much to operate as a modern air-
cooled system.
Rain water collection
It has been done throughout history. Minimal filtering is required before storage and reuse if the
collected rainwater is used for toilets, landscape irrigation and in some cases process use. More
advanced filtration such as ultraviolet water purifiers may be required depending on length of time
stored and desired water usage. Rain water collection is usually quite effective, because most large

4. commercial/industrial buildings have large, flat roofs that provide lots of space for collection. Imagine
collecting rainwater to water your companies’ rooftop garden.
Strategies Used for Water Conservation System
 One strategy in water conservation is rain water harvesting. Digging ponds, lakes, canals,
expanding the water reservoir, and installing rain water catching ducts and filtration systems on
homes are different methods of harvesting rain water. Harvested and filtered rain water could
be used for toilets, home gardening, lawn irrigation, and small scale agriculture.
 Another strategy in water conservation is protecting groundwater resources. When
precipitation occurs, some infiltrates the soil and goes underground. Water in this saturation
zone is called groundwater. Contamination of groundwater causes the groundwater water
supply to not be able to be used as resource of fresh drinking water and the natural
regeneration of contaminated groundwater can takes years to replenish. Some examples of
potential sources of groundwater contamination include storage tanks, septic systems,
uncontrolled hazardous waste, landfills, atmospheric contaminants, chemicals, and road salts.
Contamination of groundwater decreases the replenishment of available freshwater so taking
preventative measures by protecting groundwater resources form contamination is an
important aspect of water conservation

5.  An additional strategy to water conservation is practicing sustainable methods of utilizing
groundwater resources. Groundwater flows due to gravity and eventually discharges into
streams. Excess pumping of groundwater leads to a decrease in groundwater levels and if
continued it can exhaust the resource. Ground and surface waters are connected and overuse of
groundwater can reduce and, in extreme examples, diminish the water supply of lakes, rivers,
and streams. In coastal regions, over pumping groundwater can increase saltwater intrusion
which results in the contamination of groundwater water supply. Sustainable use of
groundwater is essential in water conservation.
 A fundamental component to water conservation strategy is communication and education
outreach of different water programs. Developing communication that educates science to land
managers, policy makers, farmers, and the general public is another important strategy utilized
in water conservation. Communication of the science of how water systems work is an
important aspect when creating a management plan to conserve that system and is often used
for ensuring the right management plan to be put into action.
Water Conservation in the Pharmaceutical Industry
Water and energy are intertwined. Not that long ago, water and energy conservation contributed little
more.
 The pharmaceutical industry requires consistent, high-quality water for production and
wastewater treatment than idle discussion when specifying water systems. Today, companies
must explore innovative ways to conserve water, reduce energy consumption, and minimize
waste. In particular, the pharmaceutical industry requires consistent, high-quality water for
production and wastewater treatment to meet the demands of ever-stricter regulatory

6. discharge limits. To meet these challenges, companies must question conventional thinking and
typical approaches and explore new technologies and solutions to remain competitive.
 Because of this increased focus on water and energy, companies are evaluating new
technologies and integrated solutions to reduce water consumption and increase energy
efficiency. These new technologies and solutions cannot, however, compromise the
dependability and robustness demanded by the marketplace. There is perhaps no better
example of the need for dependable water solutions and product safety than in the
pharmaceutical industry.
 For pharmaceutical applications, there are three main drivers that force the issues of utility
conservation into product design: long-term lifecycle costs, regulatory requirements and
conservation/corporate responsibility.
 Operating cost reduction has become increasingly important for pharmaceuticals and virtually
every other industry to allow companies to operate as efficiently as possible. Reducing the cost
of ownership on a water system is an important aspect of system design. Exploring new
methods to reduce the cost of treating water, wastewater discharge, and utility expenses
challenges decades-old system designs. Many cost savings techniques can actually offer
enhanced reliability and performance of conventional water systems, while lowering cost of
ownership.
 Achieving regulatory requirements on a water system design usually includes two distinct areas
of responsibility in a pharmaceutical application: maintaining minimum water quality standards
for discharge or reuse within the facility and meeting discharge volume from the facility. There
are specific contaminant limits on the discharge of water into municipalities or other waste
streams. Exceeding these limits can result in severe financial penalties or put a plant’s operation
at risk. In particular, pharmaceutical manufacturers must operate within strict national and local
regulatory limits.
 Finally, conservation of natural resources and public perception of the pharmaceutical
manufacturers is critical for the image of these companies. Companies can receive negative
public perception and ratings from regulatory bodies as well as shareholders, if not operating at
an optimal level. More and more, companies want to be recognized for the efficient use of
natural resources and a gentle global footprint. In addition, companies experience increased
scrutiny and pressure from various entities including the public, regarding concerns about
pharmaceuticals in drinking water. So, ensuring tight management of water supply is a serious
and critical point for pharmaceutical manufacturers—both in the manufacturing process and in
product development.
Microbial Contamination
Water is used widely during the production of pharmaceutical products as a direct ingredient as well as
indirect uses such as formulation, rinsing, sanitizing and cleaning. Most high quality makeup water
systems used within pharmaceutical production have some element of recirculation inherent in the
system design. When water is not needed, water systems typically go into a recirculating standby mode
to control microbial proliferation within the water and on the wetted surfaces of the water system. This
conventional approach has been used for decades and has been considered the best ‘in situ’ approach
for controlling microbial contamination. Often, microbial contamination is the most difficult, and costly,
aspect of the water system design. While chemical and organic impurities can usually be managed with
little difficulty, proliferation of bacteria, viruses and other organisms can challenge even the best system
designs.

7. Operating costs have become increasingly important for pharmaceutical and virtually every other
industry.
In an effort to build robustness into the water systems of a pharmaceutical facility, many of these
systems are built with a 2 x 100% redundancy approach. This ensures the water system is always
available when needed. All water systems require periodic maintenance monitoring and adjustments,
and a redundant water system approach allows one train to be available while the other train is being
serviced or maintained. This redundant water train will continually recirculate while in the standby
mode, and will consume water and electricity, and produce wastewater, nearly 100% of the time since it
is by nature a standby or backup system.
Technology Developments
Recent technology developments for pharmaceutical water systems eliminate the need to continually
recirculate water. The S3® system, a new technology provided by Siemens Water Technologies, uses a
sanitize/start/stop approach rather than a recirculating water system design. A traditional water system
constantly recirculates water, which consumes electricity for pumps, ultraviolet lights, instruments and
other devices. Often the water must be heated or cooled to maintain adequate water temperature
specifications. Additionally, certain unit processes such as reverse osmosis produce a waste stream
during operation. A recirculating water system, even if it is not currently producing water for
production, is producing waste that must be discharged or treated prior to discharge. These systems can
consume valuable raw water, consume electrical and steam utilities and produce a wastewater stream
even if the water system is not being used in the production process.
A sanitize/start/stop design eliminates most of this waste by shutting down the water system when not
needed. While in the standby mode, the system will briefly turn on and receive periodic heat
sanitization during extended periods of non-use. These sanitization periods are quick and relatively low
temperature (typically 60°C) rather than the more typical 80 to 85°C. The brief but frequent sanitization
periods are very effective at challenging microbial proliferation within a water system. When the
pharmaceutical production requires water, the system performs a brief pulse sanitization just before
water is sent to the manufacturing process. This ensures the water system is freshly sanitized for
optimal water quality when it is needed. Standby or redundant trains can now sit relatively idle,
receiving periodic pulse sanitizations to maintain water quality. Just like conventional water systems, the
sanitize/start/stop design can be combined with chemical cleaning, chemical sanitization and
conventional heat sanitization to address microbial contamination and biofilm formation within the
water system.
The economic and water volume savings from the sanitize/start/stop approach can be dramatic,
sometimes saving many millions of gallons of water per year. Large water systems, redundant trains,
high raw water costs, high discharge water costs, and water discharge limitations can greatly impact the
total savings. While the savings are greater on larger systems, even single-train, relatively small water
systems with moderate water costs still result in rapid payback and significant savings.
For example, a healthcare products manufacturer in the Southeast USA is a major manufacturer of
vision care products. Like most companies, they evaluated solutions for reducing water consumption
and optimizing the production of their products. The company required a 150 gallon-per-minute
treatment plant producing United States Pharmacopeia (USP) Purified Water quality water. System
validation was unnecessary for this application.

8. The specifics for this example water system include:
 150 GPM make-up water requirement
 Operation: 7 hours / day, 5 days / week, 350 days / year
 Feed water cost: $1.33 / 1000 gallons
 Wastewater discharge cost: $2.77 / 1000 gallons
 Electrical cost: $0.05 kWh
The following cost saving analysis includes an annual savings and 10-year projection that includes
projected utility cost increases.
The total water system cost is less than the 10-year projected savings. The uniquely designed system can
quickly pay for itself, typically with a payback period of six to 24 months after which the savings drops
immediately to the bottom line of the manufacturer. But remember, the water system was required
regardless of the savings.
Water Reuse
In an effort to reduce raw water consumption and wastewater production from its product
manufacturing process, this same healthcare products manufacturer implemented a water reuse
system. The primary driver was strict regulations on wastewater discharge from the facility. Failure to
recover their wastewater and reuse it as feed water would have resulted in severe financial penalties,
crippling the facility’s growth ability.
The wastewater includes a proprietary organic compound introduced during the manufacturing process.
It is critical to remove this contaminant from the wastewater stream before it can be returned to the
feed of the system for reuse. Additionally, while important to remove the organic compound, it was also
desirable to selectively retain a proprietary inorganic compound in the wastewater stream. By removing
the organic contaminant and leaving the selective inorganic compound intact, the wastewater stream
could be returned to the feed system and used again, safely and efficiently.
Membrane solutions such as ultrafiltration, reverse osmosis, nano filtration, micro filtration and ceramic
membranes were all considered as possible solutions for this process. Ultimately, nano filtration was
selected because of its process characteristics in removing the organic contaminant while having
minimal impact on the selective inorganic compound in the process.
The company was able to recover and reuse more than 52 million gallons a year of its waste stream. This
equates to a savings of approximately $3.4 million over a 10-year period. These savings do not include
the regulatory penalties avoided or the financial impact of the facility’s ability to grow in their respective
marketplace.

9. Pharmaceutical compounds are typically produced in batch processes leading to the presence of a wide
variety of products in wastewaters which are generated in different operations, wherein copious
quantities of water are used for washing of solid cake, or extraction, or washing of equipment. The
presence of pharmaceutical compounds in drinking water comes from two different sources: production
processes of the pharmaceutical industry and common use of pharmaceutical compounds resulting in
their presence in urban and farm wastewaters. The wastewaters generated in different processes in the
manufacture of pharmaceuticals and drugs contain a wide variety of compounds. Further, reuse of
water after removal of contaminants, whether pharmaceuticals or otherwise, is required by industry. In
view of the scarcity of water resources, it is necessary to understand and develop methodologies for
treatment of pharmaceutical wastewater as part of water management. In this review, the various
sources of wastewaters in the pharmaceutical industry are identified and the best available technologies
to remove them are critically evaluated. Effluent arising from different sectors of active pharmaceutical
ingredients (API), bulk drugs, and related pharmaceutics, which use large quantities of water, is
evaluated and strategies are proposed to recover to a large extent the valuable compounds, and finally
the treatment of very dilute but detrimental wastewaters is discussed. No single technology can
completely remove pharmaceuticals from wastewaters. The use of conventional treatment methods
along with membrane reactors and advanced post treatment methods resulting in a hybrid wastewater
treatment technology appear to be the best. The recommendations provided in this analysis will prove
useful for treatment of wastewater from the pharmaceutical industry.

10. Water Conservation in the Garments Industry
Water is everywhere but still the problem of water shortage is there all over. Something important to
note – everything we buy or use has an indirect water footprint – manufacturing, harvesting the raw
materials, finished products or store shelf near you. As per the World Bank, textile dyeing and treatment
are responsible to around 20% of industrial water pollution. The garment industry has always relied
upon abundant amounts of water to produce the clothes we wear. That favorite cotton T-shirt in your
closet (material, production and transport phases of one cotton T-shirt) require:
 Fossil Fuel – 0.5 Kgs
 Pesticides – 0.004 Kgs
 Fertilizers – 0.11 Grams
 Water – 2,650 Litres
Up to 100 liters of fresh water, and very high amount of energy, is required to dye just one kilogram of
cotton fabric. These challenges are worsened in regions facing acute water scarcity. Many of the world’s
largest textile-producing nations – to name few – China, India, Pakistan, Bangladesh, Brazil – are also
those most vulnerable to water shortages.
This attitude change is putting pressure on industry to demonstrate that their supply chains are clean
and transparent. Mandatory stringent environmental legislation has been introduced and government is
enforcing strict pollution laws. The United Nations is warning that half the global population could be
facing water shortages by 2030.

11. All of these factors, brings in the most pressing challenges – reduce water usage. Great deal can be done
today to reduce the industry’s reliance on water. Companies have realized that the way we produce
clothes has a direct impact not only on the world’s valuable clean water resources but on the apparel
industry’s bottom line. Hence, technologies and innovation have been introduced by many companies
across the globe.
Some of the innovative used by companies worldwide are:
 Adds color to textiles sans the wet stuff. The patented process system adds PVC-free inks to a
paper carrier, then heat-transfers the dyes from the paper to the surface of the fibers at a
molecular level. Applying color in this fashion not only uses 90% less water than conventional
methods.
 The H2O-free technology imbues a pressurized form of carbon dioxide with liquid-like
properties, allowing it to penetrate textile fibers and disperse preloaded dyes without extra
chemical agents. Once the dyeing cycle is completed, the CO2 is gasified to recover the excess
dye before cycling back into the dyeing vessel for reuse—no muss, no fuss, and with far less
energy than conventional methods.
 Using ozone technology that slashes their use of water, energy, and chemicals. The use of ozone
technology allows us to clean up the excess indigo without the use of water and pocket-
whitening chemicals altogether.
 Transforming air in the atmosphere into “nano-bubbles” that soften fabrics using 98% less water
and 79% less energy than traditional methods.
 Avitera process which harnesses just three to five gallons of water per two pounds of material,
compared with the 26 gallons conventional methods require. Plus, nearly 90 percent of the dye
bonds to the cotton fibers, leaving far less unfixed dye to rinse off.
 Using recyclable carbon dioxide (supercritical CO2) as the application medium to infuse colour
into fabric instead of water. This completely eliminated the use of water in the textile dyeing
process and would benefit the industry in years to come.
 Digital textile printing requires mills to invest heavily in machines and to retrain staff and use
high-quality specialist inks, but it is now cost-effective for higher value fabrics. Digital printing
allows mills to print an almost unlimited array of colours and complex patterns in short runs. It is
also a very clean process that minimizes waste and substantially reduces water and energy
consumption.
 Usage of PET bottles in its jeans to increase their durability and lifecycle.
 Breaks down recyclable plastic and spins it into usable fibers that can then be sold and mixed
with other fibers, including wool and cotton. Recycling the fibers means less water used to grow
and prepare new materials, and mixing materials can also mean longer-lasting products.
 Companies lead the way with new technologies that save water and energy.

12.  As the garment industry is now discovering, economic profitability is as dependent on
introducing and inspiring good environmental habits. With a new mindset comes better water
conservation, an increasingly important benchmark for today’s sustainable garment industry
Water-Saving Technologies in home irrigation system
WaterSense Labeled Irrigation Controllers
WaterSense labels weather-based irrigation controllers, a type of "smart" irrigation control technology
that uses local weather data to determine when and how much to water. WaterSense labeled irrigation
controllers can save you water, time, and money when compared to standard models.
Soil Moisture Sensors
Soil moisture–based control technologies water plants based on their needs by measuring the amount
of moisture in the soil and tailoring the irrigation schedule accordingly. WaterSense has issued a Notice
of Intent to label soil moisture–based control technologies.
Rainfall Shutoff Devices
Rainfall shutoff devices turn off your system in rainy weather and help compensate for natural rainfall.
This inexpensive device can be retrofitted to almost any system.
Rain sensors
Rain sensors can help decrease water wasted in the landscape by turning off the irrigation system when
it is raining.
Sprinkler Heads
Certain types of sprinkler heads apply water more efficiently than others. Rotary spray heads deliver
water in a thicker stream than mist spray heads, ensuring more water reaches plants and less is lost to
evaporation and wind. WaterSense has issued a Notice of Intent to label landscape irrigation sprinklers.
Micro-Irrigation
Micro–irrigation or drip systems are generally more efficient than conventional sprinklers, because they
deliver low volumes of water directly to plants' roots, minimizing losses to wind, runoff, evaporation, or

13. overspray Drip irrigations systems use 20 to 50 percent less water than conventional pop-up sprinkler
systems and can save up to 30,000 gallons per year. Consider installing drip around trees, shrubs, and
gardens in place of a conventional sprinkler system. For more information on drip systems or micro-
irrigation.
Benefits of Water Conversation System
 Water utility cost reductions from 50% to 90%
 Limit the impact of budgeting uncertainties associated with large yearly water utility rate
increases
 Reduces load on municipal water and sewage treatment facilities
 If you save water it can save your money bills.
 Reduction in interior water use cuts waste water flows, especially overflowing of gutters which
contaminates the environment.
 Environment benefits include eco system and habitat protection.
 Water conservation helps in improving the quality of your drinking water.
 Saves money

14.  Protects drinking water resources
 Minimizes water pollution and health risks
 Reduces the need for costly water supply and new wastewater treatment facilities
 Maintains the health of aquatic environments
 Saves energy used to pump, heat, and treat water
References
 "Water conservation « Defra". defra.gov.uk. 2013. Retrieved January 24, 2013.
 "Cases in Water Conservation: How Efficiency Programs Help Water Utilities Save Water and
Avoid Costs" (PDF). EPA.gov. US Environmental Protection Agency.
 Hermoso, Virgilio; Abell, Robin; Linke, Simon; Boon, Philip (2016). "The role of protected areas
for freshwater biodiversity conservation: challenges and opportunities in a rapidly changing
world". Aquatic Conservation: Marine and Freshwater Ecosystems. 26 (S1): 3–11.
doi:10.1002/aqc.2681.
 Vickers, Amy (2002). Water Use and Conservation. Amherst, MA: water plow Press. p. 434. ISBN
1-931579-07-5.
 Geerts, S.; Raes, D. (2009). "Deficit irrigation as an on-farm strategy to maximize crop water
productivity in dry areas". Agric. Water Manage. 96 (9): 1275–1284.
doi:10.1016/j.agwat.2009.04.009.
 Kumar Kurunthachalam, Senthil (2014). "Water Conservation and Sustainability: An Utmost
Importance.". Hydrol Current Res.
 "Description of the Hydrologic Cycle". http://www.nwrfc.noaa.gov/rfc/. NOAA River Forecast
Center. External link in |website= (help)
 "Potential threats to Groundwater". http://www.groundwater.org/. The Groundwater
Foundation. External link in |website= (help)
 Jorge A. Delgado, Peter M. Groffman, Mark A. Nearing, Tom Goddard, Don Reicosky, Rattan Lal,
Newell R. Kitchen, Charles W. Rice, Dan Towery, and Paul Salon (2011). "Conservation Practices
to Mitigate and Adapt to Climate Change". Journal of Soil and Water Conservation.
 "Persuading the public to reduce bottled water consumption" (pdf). European Commission. 3
September 2015.
 "Water - Use It Wisely." U.S. multi-city public outreach program. Park & Co., Phoenix, AZ.
Accessed 2010-02-02.
 Santos, Jessica; van der Linden, Sander (2016). "Changing Norms by Changing Behavior: The
Princeton Drink Local Program". Environmental Practice. 18 (2): 1–7.
doi:10.1017/S1466046616000144.
 U.S. Environmental Protection Agency (EPA) (2002). Cases in Water Conservation (PDF) (Report).
Retrieved 2010-02-02. Document No. EPA-832-B-02-003.

15.  Albuquerque Bernalillo County Water Utility Authority (2009-02-06). "Xeriscape Rebates".
Albuquerque, NM. Retrieved 2010-02-02.
 Heberger, Matthew (2014). "Issue Brief" (PDF). urban Water Conservation and efficiency
Potential in California: 12.
 "Time for universal water metering?" Innovations Report. May 2006.
 Environment Canada (2005). Municipal Water Use, 2001 Statistics (PDF) (Report). Retrieved
2010-02-02. Cat. No. En11-2/2001E-PDF. ISBN 0-662-39504-2. p. 3.
 EPA (2010-01-13). "How to Conserve Water and Use It Effectively". Washington, DC. Retrieved
2010-02-03.
 Pimentel, Berger; et al. (October 2004). "Water resources: agricultural and environmental
issues". BioScience. 54 (10): 909. doi:10.1641/0006-3568(2004)054[0909:WRAAEI]2.0.CO;2.
 http://www.home-water-works.org
 http://www.pnas.org/content/early/2014/02/26/1316402111
 "Water-Saving Technologies". WaterSense: An EPA Partnership Program. US Environmental
Protection Agency.
 UNEP, 2011, Towards a Green Economy: Pathways to Sustainable Development and Poverty
Eradication, www.unep.org/greeneconomy
 Wastewater Reuse and Current Challenges - Springer. doi:10.1007/978-3-319-23892-0.
 Elimelech, Menachem; Phillip, William A. (2011-08-05). "The Future of Seawater Desalination:
Energy, Technology, and the Environment". Science. 333 (6043): 712–717.
doi:10.1126/science.1200488. ISSN 0036-8075. PMID 21817042.
 Han, Songlee; Rhee, Young-Woo; Kang, Seong-Pil (2017-02-17). "Investigation of salt removal
using cyclopentane hydrate formation and washing treatment for seawater desalination".
Desalination. 404: 132–137. doi:10.1016/j.desal.2016.11.016.
 Seeger, Eva M.; Braeckevelt, Mareike; Reiche, Nils; Müller, Jochen A.; Kästner, Matthias (2016-
10-01). "Removal of pathogen indicators from secondary effluent using slow sand filtration:
Optimization approaches". Ecological Engineering. 95: 635–644.
doi:10.1016/j.ecoleng.2016.06.068.
 Vries, D.; Bertelkamp, C.; Kegel, F. Schoonenberg; Hofs, B.; Dusseldorp, J.; Bruins, J. H.; de Vet,
W.; van den Akker, B. "Iron and manganese removal: Recent advances in modelling treatment
efficiency by rapid sand filtration". Water Research. doi:10.1016/j.watres.2016.11.032.
 "Slow Sand Filtration". CDC.gov. May 2, 2014.
 Gerba, Charles P.; Betancourt, Walter Q.; Kitajima, Masaaki. "How much reduction of virus is
needed for recycled water: A continuous changing need for assessment?". Water Research.
doi:10.1016/j.watres.2016.11.020
 Chandrakanth Gadipelly, Antía Pérez-González‡, Ganapati D. Yadav*, Inmaculada Ortiz, Raquel
Ibáñez‡, Virendra K. Rathod, and Kumudini V. Marathe. “Pharmaceutical Industry Wastewater:
Review of the Technologies for Water Treatment and Reuse” Ind. Eng. Chem. Res., 2014, 53
(29), pp 11571–11592