Bottled Water University Edition: Cost, Quality & Supply

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Americans enjoy one of the safest, most comprehensive and lowest cost public drinking water systems in the world. Though contaminants can and do threaten the nation’s water safety, a wide range of cost effective products are available to deliver clean tap water, and many municipalities are taking action to reduce risks associated with contamination.

In this section we discuss tap water and wells along with water filters, water fountains, bottle-less water coolers, and reusable containers (i.e., reusable metal and plastic bottles).

Banning bottled water does not necessarily result in a net loss of revenue for colleges and universities. Indeed, educational institutions can save money by eliminating or reducing complimentary bottled water at university-sponsored catered events and administrative functions. These bottled water giveaways could represent a substantial amount of cost savings. These savings should be compared to the revenue generated by bottled water purchases. Whether a university will save or lose money depends on a variety of factors such as the size and frequency of events where the university provides complimentary bottled water, the size of the student body and their consumption habits, and the scope of on-campus retail operations. These factors will obviously vary from school to school. If a net loss is predicted, specify whether the university will attempt to offset the cost through the sale of alternative beverages, reusable bottles, etc., or if it will accept and absorb the cost. Just remember to offset Bottled water is roughly 750 to 2700 times more expensive than tap water lost revenue by factoring in gains realized by eliminating the purchase and provision of free bottled water.

Tap Water

On average, tap water costs 0.2 cents per gallon in the U.S (EPA, 2004) – roughly 750-2,700 times cheaper than bottled water on a per gallon basis, although this cost varies regionally–see Figure 4. For instance, the City of Seattle determined that bottled water costs $8 per gallon while tap water costs 0.3 cents per gallon—nearly 2,700 times less (from Seattle’s Executive Order Restricting Bottled Water; see Policies).

Over 90 percent of U.S. municipal water systems regularly meet or exceed the EPA’s stringent regulatory and monitoring requirements (EPA, 2007). Federal law requires water utilities to issue annual Consumer Confidence Reports (CCRs), also called “right-to-know” reports, identifying the sources and quality of municipal water. Municipal water customers should receive a CCR in the mail by July 1 each year, although customers of systems serving fewer than 10,000 people may not receive reports via mail. Many CCRs are available online at www.epa.gov/safewater/dwinfo.htm and can be requested from the local water supplier or from the EPA’s Safe Drinking Water Hotline (800-426-4791). Reported levels in CCRs are based on annual averages, but spikes can occur at certain times—for example, when spring rains raise nitrate levels (CR, 2007a).

These resources help consumers read and understand CCRs:

Consumer Reports, “Deciphering your water report”, May 2007
Campaign for Safe and Affordable Drinking Water, http://www.safe-drinking-water.org/rtk.html

Contaminants come from a variety of sources, including municipal and agricultural pollution, wells, faulty and aging pipes, flawed water treatment systems, and even from the natural environment (see Addendum VII). There are three types of contaminants: microbes, chemicals, and metals (CR, 2007a), all of which can cause serious health effects. Water contamination is of special concern to children, the elderly, pregnant women, and those with weakened immune systems. These populations may experience adverse health effects even if contaminants are at or below legal limits.

Although rare, the safety of a municipal water supply is sometimes so threatened, that a local agency will issue a “boil water advisory.” These advise residents to boil water for several minutes to kill bacteria and viral agents prior to drinking. Boil water advisories often occur after a contamination has been detected. For a list of up-to-date advisories, visit http://www.water.ca/US-bwa.asp.

Currently, approximately 69 percent of tap water in the United States receives added fluoride in their municipal water supply in a process known as “fluoridation”. The process began in the 1940’s as a way to combat tooth decay by exposing someone’s teeth to fluoride throughout his life and is now very common (CDC, 2009). Although the CDC claims that fluoride treatment is safe, others are concerned that the levels might be too high as to cause health problems in infants which outweigh any benefits in oral hygiene (EWG, 2007). If desired, choose a filter that can remove fluoride from RPN’s Product database.

While safety is legally regulated and monitored, “drinkability” is more subjective, including aesthetic characteristics such as odor, appearance, and taste. These subjective qualities, however, can be equally vital in ensuring a successful switch from bottled to tap water. Consumers may reject perfectly safe water if they consider its aesthetic qualities displeasing. Water tests and student polls may help a university identify and appropriately address any unpleasant non-health-related characteristics of its tap water supply.

Wells

Private wells supply drinking water for over 40 million Americans. Well water is not regulated by the EPA and should therefore be tested annually by a state-certified laboratory. Contaminants of particular concern for well users include arsenic, nitrates, coliform bacteria, and total dissolved solids (TDS) (GG, 2007). Additionally, tests for radon and pesticides should also be conducted if they are known to exist in the area. Contact the state or local health department to find out which contaminants may be problematic in a particular region. For more information about wells and well water, contact the Water Systems Council at www.wellcarehotline.org or 888-395-1033.

For more information on common tap water contaminants and their health effects, see Addendum VII and NRDC’s Drinking Water Report.

Water Filters

Where safe, clean, aesthetically appealing tap water is available, filters are an unnecessary expense. However, it is important to use filters when water contains contaminants or has undesirable subjective qualities such as unpleasant taste or smell. Water filters range widely in cost, quality and supply. There are two general types of filters: point-of-entry (whole building) and point-of-use (counter top, carafes, faucet mount, under counter).

Water filtration can be accomplished through a variety of methods, including absorption, adsorption, filter membranes, distillation, and disinfection. Addendum VII describes some of the most common filtration methods.

Filters come in a wide array of shapes, sizes, and styles to suit performance, convenience, and aesthetic needs. Enhanced features include LED readout screens, electronic touchpads, digital clocks, and monitors or alarms that indicate the need for cartridge replacement. Addendum IX describes some common filter styles.

Consider the following when choosing a water filter:

Contaminants. Which contaminants need to be removed and which filtration method removes them? See Determine Water Quality (Box 1) and the Tap Water and Wells sections above for more information on how to determine tap water quality. See the NSF International web site for a database of drinking water treatment units certified to remove specific contaminants.
Location. Where will filters be located (counter, cabinet, floor, refrigerator) and how much space is required and available?
Replacement. How often do filter cartridges or membranes need to be replaced?
Installation. Is the unit and filter easy to install, clean and change (GG, 2002)?
Performance. Will the filtration unit maintain a steady flow rate throughout its lifespan (GG, 2002)?
Maintenance. Who will maintain and clean the unit? When? Will training be required?
Resources. How much energy and excess water does the unit use to filter water?
Price. Factoring in all of the below, estimate cost per gallon of filtered water:
- Filtration unit price
- Annual filter and unit replacement costs
- Cost of electricity required to operate the unit
- Maintenance and cleaning costs, including cleaning products and staff time

Benefits of water filters include:

Low Cost and Wide Availability. Filters are widely available and consistently cheaper than bottled water. One manufacturer claims that one pour-through filter can replace 300 standard bottles of water (16.9 oz.) (TBTF, n.d.).

Suitability to Wide Range of Needs. Filters allow users to choose which substances are removed from their water (CR, 2007a). The type and quantity of contaminants removed depends on the filtration method, filter style, and manufacturer model. Rely on independent certifications to verify which contaminants are

Box 2: Used Filter Take Back and Recycling
Since 1992, the European branch of the BRITA company has been collecting filter cartridges to separate and recycle component materials (TBTF, n.d.). However, when Clorox bought BRITA North America (the most popular water filter system in the U.S) (TBTF, n.d.), this practice was not extended to the U.S until January 2009.

A few smaller filter manufacturers also offer refillable cartridges and/or filter takeback programs – such as TerraFlo and Abundant Earth.

filtered (see Standards).

Removal of Contaminants in the Water System. Filtration addresses pollutants that may have entered the water between the water treatment site or municipal pipes and the point-of-use at the faucet or fountain.

Less than 100% effective. No filter or filtration method removes one hundred percent of all types of contaminants. Combining filtration methods can come close, but even then there is debate over which substances are considered harmful and which are considered innocuous or even beneficial (i.e. certain minerals).
Can be Costly. Filtration can be expensive. In addition to the upfront purchase of the filtration unit (anywhere from $15 to $1500 for home units and much more for institutional units), there can be costs associated with installation, energy use, filter replacements, maintenance and cleaning.

Performance and Aesthetics. Filters have a multitude of performance and aesthetic issues. For example, some units filter water very slowly, while others take up a large amount of counter or cabinet space. See Addenda VIII and IX for a comparison of the pros and cons of common filtration methods and filter styles.

Box 3: Filter Labeling Requirements
In California, Wisconsin, Massachusetts, and other states, manufacturers are required by law to disclose in product literature information such as filter replacement cost, filtration method and style, and contaminants removed.

Materials and End-of-Life Management. A large majority of filters and filter components are manufactured using petroleum-derived plastic. Depending on the unit, disposable cartridges must be replaced anywhere from monthly to once every few years. Currently, most filter cartridges are not recyclable and most manufacturers do not offer filter take-back programs (See Box 2). Thus, most filter cartridges are disposed of in landfills. Compounding the waste problem is the fact that the contaminants trapped in the filters can easily leach into water and soil, or be released into the air if incinerated.

Fountains

Whether using existing drinking fountains or purchasing new ones, there are several practices that can help decrease costs, reduce energy usage, and improve equipment function.

In an average week, a refrigerated fountain uses 8.5 to 10.5 kWh of electricity (NC, 2004). While this number varies depending on frequency of use, air and water temperature, and unit size, this corresponds to a cost of $30-38 per fountain per year (based on average North Carolina electricity rates) (NC, 2004). There are several ways to reduce this electricity use and subsequent costs, including:

Increase the water temperature dispensed by the fountain. Most cold-water fountains are set at 40-45 degrees Fahrenheit. Increasing this to 50 degrees will decrease the energy used for refrigeration while still protecting against bacterial growth.
Insulate the unit, especially the piping, chiller, and storage tank, to save energy (DOE, 2001).
Disconnect the fountain during nights, weekends, or other periods of non-use to stop the refrigeration unit from running. Note that disconnecting the fountain for extended periods can lead to bacterial growth inside the unit. Vendors recommend not leaving the fountain disconnected for more than 8 hours at a time. Consider the amount of effort involved in disconnecting the unit. Can the fountain just be unplugged? Will the fountain dispense without electricity? Will users react negatively to getting less chilled or unchilled water? Calculate the potential cost savings of unplugging your fountains here http://www.p2pays.org/ref/40/39997.pdf.
Use a timer to switch the unit’s refrigeration system off when not in use. Automatic timers are relatively cheap ($10) and easy to install for plug-in fountains. However, it is not always cost-effective to install a timer on fountains that are already wired into the building’s electrical system (MEO, 2005). This cost can be avoided if fountains are wired into the building’s light switch circuits at the time of installation or building construction. Again, vendors recommend not leaving the fountain disconnected for more than 8 hours at a time, as bacteria can proliferate much more quickly in water at room temperature.
Purchase unrefrigerated units to avoid energy costs altogether. So called “direct feed” water fountains dispense water directly from the tap, similar to standard water faucets, but are designed for drinking. Water that comes directly from underground municipal pipes tends to be naturally cooler than room temperature.

While the cost of fountains can seem prohibitive, it is often less expensive over the long run to upgrade or install fountains than it is to purchase bottled water. The County of Santa Clara, California, analyzed the costs of switching from large, multi-serve bottled water coolers to tap water fountains (SCC, 2008). The county spends $131,151 per year on its bottled water contract. They found that installing one fountain would cost $10,000 (75 percent labor costs and 25 percent materials). This cost would double if the installation was considered ‘difficult’, meaning that hazardous materials or significant structural obstacles were present.

To convert from bottled coolers to fountains in all of its facilities, the County estimated that it would cost $369,000-539,000, with annual maintenance and service costs totaling $10,000-20,000 (assuming all simple installations). The County also noted that they would need to “divert existing staff from maintenance work or hire extra help” to service the fountains (SCC, 2008). It was estimated that after acquiring the necessary funds, it could take up to three years to make the switch.

Extrapolating these costs, the switch has a five-year return on investment. After the five-year mark, they would pay $10,000-20,000 per year for fountain maintenance, compared to $131,151 each year for their bottled water contract. All told, the County estimates savings of up to $500,000 over ten years (see Table 2). If bottled water prices increase during that time, savings on the switch could also increase.

Table 2: Long term cost savings from water fountains

Cost of Bottled Water	Cost of Drinking Fountains	Savings over 5 Years
$655,755 (5 year contract)	$419,000 - $639,000 (Installation in year 1 and yearly maintenance costs for 4 years)	$16,755 - $236,755

Water fountains require regular maintenance to ensure sanitary conditions. Schedule regular maintenance for each fountain and order high-quality replacement parts. Ask fountain vendors to recommend reputable parts suppliers.

Be aware that proper cleaning and maintenance can be difficult with filtered drinking fountains. Typically, water dispensed from these units passes through a filter before reaching the water storage tanks. Because the filter usually removes chlorine – a sanitizing agent – the stored water is more susceptible to bacterial growth. This can lead to the development of a bacterial “biofilm” that coats the internal fountain components. When this happens, the fountain must be completely dismantled so the components can be manually scrubbed and sanitized. In most cases, it is impossible to access the inside of the water storage tank to manually sanitize this area (Doughty, 2008).

Install fountains in easily accessible, highly visible areas such as main hallways, waiting areas, cafeterias, and next to vending machines. This will increase their use and deliver a better return on investment. Create educational materials or signs that explain why bottled water is no longer available and encourage the use of tap water, fountains, and reusable bottles.

Bottle-Less Water Coolers

Bottle-less water coolers are a great alternative to large bottled water dispensers. These plumbed-in coolers connect directly to a tap water line and are typically equipped with filtration systems. Bottle-less water coolers are very similar in construction to bulk bottled water units, except they draw water from the tap. Water flows from a building’s tap through a filter inside the cooler and is then either chilled directly or piped to a stainless steel storage reservoir to be cooled before dispensing.

Factoring in the costs of cooler rentals, water delivery, and maintenance, the cost of bottle-less filtered water coolers is typically half the cost of delivered bottled water. Depending upon the usage, the cost savings can be as much as 80% when switching to bottle-less systems (Doughty, 2008). There are several costs to consider when purchasing a bottle-less cooler, including:

Cost of the cooler unit
Installation
Filter replacement
Maintenance and cleaning

Many vendors will bundle these costs into a monthly rate (ranging, generally, between $29 - $99 per month). Cost depends on the size, capacity and other features of the cooler. Multi-year contracts are ideal for institutions that do not want to handle ongoing cooler maintenance.

Bottle-less coolers save money, energy, labor time, and greenhouse gas emissions:

A large national bank switched 7,000 bottled water coolers to bottle-less coolers and saved approximately $5 per month per cooler – approximately $420,000 over the course of a year in electricity savings alone (Doughty, 2008).
Over an average week, a bottled water cooler uses approximately 3.5-4.5 kWh (NC, 2004), which, according to the average electricity rates in one state—North Carolina—costs $12-$17 per cooler per year. Bottle-less coolers use 30 - 50 percent less energy depending on the model and, based on the North Carolina case study, could save $4-$8 per cooler per week (Doughty, 2008).
Spectrum Water Coolers claims that “switching out bottled water for…coolers reduces greenhouse gas emissions (GHGs) by 98 percent by eliminating the bottle manufacturing, bottling, storage, distribution, delivery, as well as the removal, recycling, or dumping of used bottles” (Spectrum, n.d.).
Bottle-less coolers can also save money for other drinks such as juices and sodas in campus cafeterias. These coolers can promote the more efficient use of soda and juice concentrate, typically reducing the use of concentrate by 15 – 20 percent (Doughty, 2009).

Basic filtered bottle-less coolers come with 2-4 liter chilling or heating tanks and are less energy efficient than direct chill coolers (see below). They also require constant cleaning and maintenance to prevent bacteria build-up from stagnant water. To solve the bacteria problem, some coolers use an internal ultraviolet light to prevent bacterial growth inside the cooler and tanks. Without proper cleaning or a UV light, bacteria can end up in the water.

Direct chill technology can eliminate the bacteria issue by chilling water instantly as it passes through the cooler’s filter. Thus, water does not sit in a reservoir tank for any length of time. These coolers are energy efficient because the cooler does not have to constantly keep the water in its reservoirs cold or hot.

In some instances, installing bottle-less water coolers may be challenging. For instance, plumbing doesn’t exist in some work locations, such as construction trailers. In such cases, the best solution is to purchase a few large reusable water containers, such as the mobile insulated coolers seen at sporting events, and have each construction crew fill their jug with tap water prior to going to the worksite. Another option is an ENERGY STAR rated bottled water cooler (NC, 2004). For locations where there is not access to a water line within 500 feet or running a water line would be too costly, Spectrum has developed a “Mobile Filtered Drinking Water Cooler Solution” that may be suitable. For more information, contact Spectrum directly at 301-362-9000.

Table 3: The pros and cons of bottle-less filtered water coolers.

Pros	Cons
Decreased maintenance and cleaning (bottled coolers require monthly cleaning) No plastic bottles No need to transport the water hundreds or thousands of miles by truck or plane Unlimited supply of water Use much less energy than bottled coolers Provide clean, safe filtered water Save money	Can be more difficult to clean the unit’s complex internal structure Majority of filter cartridges cannot be recycled (see Cost, Quality, Supply section on filters for more information)

There are approximately 750,000 filtered bottle-less water coolers currently installed in the United States (compared to almost five million bottled water coolers) (Doughty, 2008). Bottle-less coolers are sold in a variety of sizes, for a range of applications, and with various optional features. Filtered bottle-less water coolers are growing at approximately two to three percent market share per year and currently make up 12 percent of the market (Doughty, 2008).

Reusable Containers

Reusable containers have lower lifecycle costs and are less harmful to humans and the environment than single-serve plastic bottles. Reusable containers are convenient to use and widely available in a variety of materials, sizes, and styles.

Many reusable containers, especially those made of metal, are lined with resins to prevent taste and odor contamination and corrosion. These resins may leach chemicals into the liquid inside. To avoid contamination, look for unlined bottles, bottles lined with water-based resins, or bottles that have been independently tested and proven not to leach chemicals. Choose bottle lids that provide a tight seal in a wide temperature range and are made of materials that can be recycled. Many manufacturers now offer several lid options in a variety of materials.

Reusable containers require proper use, care, and cleaning. Do not store full bottles in direct sun or other hot environments since this can promote bacterial growth and increase the leaching capability of some materials, especially plastics and resin linings. Use a mild soap or dishwasher detergent and warm water to clean reusable containers thoroughly but gently, including those that are deemed “dishwasher safe.” For stainless steel bottles, do not use cleansers that contain chlorine, which corrodes steel. Use a bottle brush to clean bottles with narrow mouths. Don’t forget to clean the bottle lids too, which can harbor bacteria.

Reusable bottles made of materials known to leach chemicals (such as polycarbonate plastic) should be washed by hand with warm water and mild soap in order to prevent the need for disposal and replacement. High heat dishwashers, strong detergents, and repeated washing can abrade plastic and intensify leaching. Scratches and cracks (sometimes indicated by cloudy spots) also encourage leaching, so damaged bottles should be replaced. For more advice on reusable bottles, visit this Consumer Reports website.

Metal Bottles. Stainless steel and aluminum are popular options for reusable containers. The most commonly used bottles weigh around 5-8 ounces (stainless steel is heavier), can hold a liter of liquid, and cost about $15-$30. Metal bottles are strong and durable, but can be prone to dents and will lose shape if frozen. They retain temperature well but single-walled models should not be used for hot beverages.

Metal bottles generally will not corrode or leach chemicals even when used for hot, cold, or acidic beverages. However, the interior surface of metal bottles is often coated with a food-grade resin lining. This lining can help prevent odors and metallic aftertastes. However, since many of these resins are chemically derived, they have the potential to leach toxins into any liquid they contact. Some reusable containers are lined with water-based epoxies that have been found not to leach chemicals, according to independent tests (Breum, 2001).

Some bottles are dishwasher safe, but most need to be cleaned by hand. This can prove difficult for bottles with small openings, but effective cleaning can be achieved by using a bottle brush and warm, soapy water. For dishwasher-safe stainless steel bottles, use a chlorine-free detergent since chlorine corrodes this material (Karlstrom, 2007). Depending on location and waste hauler/recycler, metal and plastic bottles and bottle caps may be recyclable.

Glass and Ceramic Bottles. These materials are also a relatively safe, low cost option for reusable containers. Glass and ceramic bottles can be repurposed from used jars and containers, thereby preventing waste. As a result, they also save energy, money, and materials because they displace the manufacturing of new bottles. Glass and ceramic bottles can also be recycled an infinite number of times and do not leach chemicals or toxins.

However, glass and ceramic both have some serious drawbacks. The first and most obvious is that they are breakable. Aside from being inconvenient, a broken bottle can pose a safety hazard. To partially address this concern, cover or wrap glass or ceramic bottles with fabric or another material that will contain the shards if broken. Glass and ceramic bottles are also heavier than metal and plastic alternatives.

Plastic Bottles. Reusable plastic water bottles cost between $3 and $50, depending on features, but most are in the $5-$10 range. Plastic bottles come in an array of shapes, sizes, colors, and styles. Some include special caps, covers, built-in filters, and even LED lights.

Polyethylene terephthalate (PET, PETE, or #1) is the plastic used for packaging most single-serving bottled waters. While it is one of the safer plastics, PET is not meant for repeated use. Bottles made from this porous plastic are difficult to clean and can harbor bacteria, especially if reused multiple times. Additionally, studies suggest that with repeated use, PET containers may release di (2-ethylhexyl) phthalate (DEHP), an endocrine-disrupting compound and probable human carcinogen, as well as antimony, an eye, skin and lung irritant at high doses (Masterson, 2006). Studies also found that toxin concentrations increase the longer the water is in the bottle (Masterson, 2006). Number 1 plastic is recyclable, but the quality degrades with each cycle so PET is typically “down-cycled” into products such as fleece apparel, carpet fiber and plastic strapping.

Certain plastics should be avoided in reusable drinking bottles, including polyvinyl chloride (PVC or #3 plastic), polystyrene (#6), and hard, transparent polycarbonate plastic (#7 and/or PC). These plastics are known to leach chemicals. Polycarbonate, in particular, has been found to leach bisphenol-A (BPA) – an endocrine disruptor, and phthalate compounds, which interfere with reproductive hormones; though it is important to note that #7 plastic is an “other” designation for plastic containers that includes polycarbonate as well as compostable bio-plastics that do not contain bisphenol-A. It also appears likely that BPA leaches at a dramatically increased rate when boiling water is used in polycarbonate containers when compared to temperate or cool water (SD, 2008).

Several studies have found that BPA can have an adverse effect on human health. The chemical has been associated with liver damage and hormone disruption. Moreover, traces of BPA have been detected in approximately 90 percent of the population. A recent article in the Journal of the American Medical Association also discovered “higher urinary concentrations of BPA were associated with an increased prevalence of cardiovascular disease, diabetes and liver-enzyme disease (JAMA, 2008).”

While some studies indicate a link between extremely low BPA doses and harmful health effects, others suggest otherwise. The FDA maintains that plastics with BPA are safe, stating “products containing BPA currently on the market are safe and that exposure levels to BPA from food contact materials, including for infants and children, are below those that may cause health effects (FDA, 2009).” The FDA, while maintaining this position, is still reviewing additional research and information as they become available.

By contrast, the Canadian government, in 2008, decided to ban the importation, sale and advertisement of polycarbonate baby bottles that contain BPA. Infants are exposed to BPA primarily through the use of polycarbonate baby bottles and although exposure levels were below acceptable limits, the government decided to enhance protections. The ban made note that only infants up to 18 months of age were likely affected and the general population was not at risk (HC, 2008).

However, despite the FDA’s assessment that BPA is innocuous, some major companies, such as Nalgene, are voluntarily removing products with BPA from their inventory. Nalgene insists that its polycarbonate bottles with BPA are safe for intended use, but is transitioning to BPA-free bottles because of “consumer requests for alternative materials (Nalgene, n.d.).”

Some safer plastics include high-density polyethylene (HDPE or #2), low-density polyethylene (LDPE or #4), and polypropylene (PP or #5). Of these, #2 plastic is preferred for its durability and wide-ranging recyclability. LDPE and PP are harder to recycle, but polypropylene is frequently used in many reusable containers.

Choose plastic bottles that are recyclable in your area and, regardless of the plastic type, minimize chemical leaching by avoiding hot liquids, harsh cleaning detergents, and heating the bottles in microwaves. Once a polycarbonate bottle becomes unsafe for drinking, it can be repurposed as a lantern or flashlight. A few companies offer plastic caps with built-in LED lights that fit on several popular brands of bottles. These “light caps” replace the bottle’s old cap. SolLight makes one model that is solar-powered, eliminating the need for batteries or other external power source.