liquid waste report

Liquid Waste Management

At Barnard College

Practices and Suggestions for

Sustainability and the Minimization

of Liquid Waste

Waste Management 3033

Prof. Peter Bower’s Liquid Waste Taskforce

December 15th

, 2008

Liquid Waste Management at Barnard College Fall 2008

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Executive Summary

This report is the product of Prof. Peter Bowers’s Waste Management course in the

Environmental Science Department of Barnard College during the 2008 fall semester. The work

represents the investigation, research, and recommendations of the students in the Liquid Waste

Taskforce. Herein, the following topics are addressed:

• Water Sources, Consumption and Financial Implications

• Combined Sewer Overflows

• Precipitation and Runoff

• Barnard’s Hazardous Waste

• Barnard’s Acid Wastewater Stream

• Gray Water

• Water Holding Tanks and the Use of Steam Power

• Greenroofs

Although New York State currently has an abundance of clean, fresh water it is a limited

resource that must be cherished and well managed. In the not too distant future, with the

advancement of green technology, it is predicted that there will be far greater conflicts caused by

the demand for potable water than oil. Therefore, it behooves Barnard to begin moving towards

sustainable water conservation and usage. These efforts will not only benefit Barnard financially,

but will also help Barnard reach its institutional commitment to reduce its carbon footprint by

30% by the year 2017. In addition, Barnard would be acting as a role model for greener living.

Our objective is to recommend concrete ways in which the College can minimize its

contribution to New York City’s combined sewage overflow [CSO]. CSOs release more than 27

billion gallons of raw sewage and polluted storm water discharge into New York Harbor each

year. This is a major threat to the biodiversity of the waterways and public health of the region.


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As a result of this research project, the following document discusses feasible policy and

infrastructure changes necessary to achieve the above goal of curtailing CSO catastrophes in

NYC. The modifications include community education; efficient storm and wastewater

management; and the installation of water reduction technology throughout the Barnard campus.

With the simple steps advocated here, Barnard can greatly reduce its negative impact on the

environment and accrue significant financial benefits for years to come.


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Liquid Waste Management Taskforce Members

Lawrence R. Sulak, II

Primary Investigator & Co-Editor

[email protected]

Adi Y. Segal

Administrative Liaison & Co-Editor

[email protected]

Contributing Authors

Clement Albano — Gray Water

Philip Hadley — Hazardous Waste & Acid Wastewater Stream

Ariel Leon — Precipitation and Runoff

Ayla Matthews — Greenroofs

Tara McAlexander — Combined Sewer Overflows

Mason McElroy — Plimpton Case Study

Lucas Momo — Water Holding Tanks and the Use of Steam Power

Luis Quero —Water Sources, Consumption and Financial Implications

Professor Peter Bower

Senior Faculty Advisor

[email protected]

Julio Vasquez & Daniel Davis

Office of Facilities Management


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Water Sources, Consumption and Financial Implications Water is provided to Barnard College through an extensive piping system maintained and

operated through the New York State Department of Environmental Protection [DEP]. New

York City’s water originates from protected aquifers rooted deep in the Catskill Mountains.

Through the Catskill, Delaware, and Croton watersheds, more than a billion gallons of water per

day are delivered to customers within City limits

as well as other municipalities who contract with

the DEP. See Figure 1 for a map of this system

from source to faucet.

The DEP charges water consumption at a

rate of $2.31 per 100 cubic feet, which is

approximately equivalent to 748 gallons. Many

buildings that have been constructed or

renovated within the past 40 years have been

mandated to install water meters. These meters

track actual water consumption and are used by

the DEP to charge the customer for their consumption. Structures not equipped with metering

systems are charged a flat frontage fee that has been developed by the DEP. Frontage

calculations take into account the length a building parallel to the street, number of floors,

numbersof dwellings, and the use of the spaces. For example, a structure with a frontage of over

50 feet is billed at a base rate of $339.40 as well as $48.55 for every additional 10 feet.

Currently the majority of Barnard’s property is billed a flat-frontage rate. The 600, 616, 620, and

Plimpton dormitories are metered because privately owned businesses occupy the street level of

Figure 1. New York City Water Sources


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these buildings and must be billed separately based on their consumption. For a case study,

please see Appendix D.

While water costs are relatively minimal in comparison to other utilities, there has been a

recent push by NYC legislators and the DEP to mandate metering in all buildings. It behooves

the Barnard administration to formulate a proactive plan such that these systems are integrated

into the College facilities at a minimal cost. As such, it is in Barnard’s best interest to develop a

transition plan for the inevitable conversion from flat-rate frontage billing to actual consumption

billing. A major component of the proposal should include conservation education as well as

plans to install a vastly more efficient water management system throughout Barnard properties.

Not only will Barnard benefit financially due to these proposed conservation efforts, the school

will also receive intangible benefits including: public recognition for green infrastructure, acting

as a trail ground and guiding light for both local and national institutions, and effecting positive

environmental change

Combined Sewer Overflows (CSOs)

Sewage systems are an important aspect of liquid waste management. There are two

common designs, one consisting of two separate piping systems and the other consisting of a

combined sewer system. In a separated sewer system storm water drains directly into a river or

reservoir, bypassing the sanitary system altogether. Many of the older cities in the United States

have combined sewer systems, including NYC. In a combined sewer system, storm water drains

directly into the sanitary system, mixing together with human excrement and other toxins. All of

this flows to sewage treatment plants which have limited capacity. When large amounts of

rainwater (more specifically precipitation runoff) fall within a short period of time, the NYC


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system’s capacity is rapidly exceeded causing the combined sewer to backup and overflow into

the storm drain system and enter the New York Harbor [see Figure 2]. The CSO sends a mixture

of sewage and storm water flowing directly into the river through drainage systems that are

intended for only storm water runoff.

The problem of inadequate

sewage system capacity is magnified by

explosions in population and

consequential increases in land

development in highly urban areas.

Population increase naturally augments

the amount of water used, and thus the

amount of water wasted. Land

development adds to the CSO problem by changing permeable, absorbent surfaces into paved

roads and rooftops that, instead of absorbing rainwater, forces rainwater to flow directly into

storm drains and gutters. Since NYC is such an over developed city, the volumes of both runoff

and wastewater flowing into the city’s combined sewer system have become so large that a CSO

is a far too often occurrence. Currently, “more than 27 billion gallons of raw sewage and

polluted storm water discharge out of 460 combined sewage overflows into New York Harbor

each year.”1 This massive volume of polluted water flowing into a natural waterway not only

impairs water quality, but it also destroys habitats and threatens public health.2

Given the current infrastructure and budget, replacement of the combined sewer system

in NYC is not feasible. The cost is so great that with an economy in turmoil the city simply

Figure 2: Combined Sewer System [D.C. Water and Sewer

Company]3


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cannot afford it. Even “end-of-pipe investments” proposed by the DEP are estimated to cost

$2.1 billion and be ineffective.1 Combined sewer systems can be effective, if and only if storm

water does not cause the combined sewer system to overflow into rivers and other natural

waterways. The most feasible way to avoid burdening the limited capacity of NYC’s combined

sewer system is to implement input controls and conservation mechanisms.

Water usage can most effectively be reduced through community education about the

limits of Earth’s natural resources. In addition, modifications to existing infrastructures such as

the installation of water-saving fixtures and technologies create automatic savings. Precipitation

runoff is controlled in similar way. Many technologies and materials exist to absorb storm water,

subsequently slowing the rate of storm water runoff into the sewer system. These include pavers,

bioretention methods, holding tanks, and green roofs which are no longer price prohibitive as in

years past. This is discussed further in the following section. In a city such as New York, any

given residence or institution can help prevent CSO occurrence by participating in source control

efforts.

Precipitation and Runoff

During periods of precipitation in New York City the majority of the water hits an

impermeable surface and flows directly into the combined sewer system. At Barnard, all

precipitation that falls onto a campus roof is drained directly into the sewer. All other

precipitation either goes to the sewer from drains imbedded in the impermeable surfaces on

campus or falls on the vegetation, effectively slowing storm water entering the sewer system.

Barnard can help reduce its contribution to CSO events by implementing some of the

following solutions. One method to slow run-off is replacing the impervious surfaces on campus


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with permeable concrete or stone. These pavers can have up to 100% surface permeability, while

also filtering pollutants. They can be used in high traffic areas for pedestrians or motorized

vehicles only need to be cleaned once or twice a year for optimal functionality. Finally, the

instillation costs are offset because fewer storm drainpipes are necessary and maintenance

expenses are lower than for most concrete or brick surfaces.

Redirecting the water coming from the roofs to more permeable surfaces, as discussed

above or to a holding tank is another solution that can be implanted on campus. Holding tanks

are used to redirect storm water in events of high precipitation and may be used to recycle water

for re-use, such as in sidewalk cleaning and irrigation. Unfortunately, given the dense urban

setting of Barnard’s campus, there appear to be few places such a tank can be effectively

installed.

One way to take advantage of the permeable surfaces already on campus is by

introducing elements of bioretention to our vegetated areas. Bioretention is a landscape design

which helps to control water volume and pollution using the chemical, biological, and physical

properties of plants, microbes and soils. For example, Lehman lawn could be reconfigured to

drain water through particular vegetation and soils which slow the rate of runoff while removing

pollutants. Storm water from the roofs could also be redirected to these areas to be filtered,

stored, and absorbed by vegetation. The minimal maintenance is similar to what is currently

performed on the existing landscape. The bioretention landscape technology can be seen in

Figure 3.

Figure 3: Bioretention landscape technology


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Green roofs are another great solution to curbing runoff, however certain buildings on

campus may not be able to sustain the weight of some types of greenroofs. Some greenroof

alternatives include sedum mats, which are low maintenance, lightweight beds of vegetation that

have high absorption rates and can be unrolled onto an impermeable layer atop a roof. An

experimental option which has been researched at the University of Maryland is a “Green

Cloak,” which consists of a fast-growing, lightweight, and low maintenance vine species. Both

alternatives have shown to have similar benefits, including insulation, water retention, and

absorption.

The easiest solution of all is education and conservation, as mentioned above.

Encouraging staff and students to take accountability for their water consumption can limit our

water output on days of precipitation by avoiding such high volume activities as washing clothes,

hosing sidewalks, using dishwashers, and activating irrigation systems. If we begin to educate

the members of our community to not only conserve water on a regular basis, but also take even

greater measures in the event of high precipitation, we would greatly decrease Barnard’s

contribution to pollution of local waterways.

Hazardous Waste

Barnard generates roughly 1,500 pounds of hazardous waste every year.4 As this cannot

be legally disposed of through normal channels, it is collected and stored at the site of generation,

for example a science laboratory or a facilities office. Through contract with Disposal Consultant

Services [DCS], the waste is picked up two times every year. The cost of each pick-up ranges

from $5,000 - $7,000, and varies according to the quantity of waste collected.


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Hazardous waste is often highly flammable or poisonous and may cause cancer. The

2007 Initial Sustainability Report lists a “hazardous waste self-audit” as a Barnard

accomplishment, but does not propose any reduction in the nearly one ton of hazardous waste

generated on campus every year. 5 Although appropriate disposal is important, the most

environmentally sound approach is to reduce the use of hazardous chemicals as much as

possible.6 Hazardous waste is classified into dozens of distinct categories,7 but the F003 category

is of particular importance for Barnard because it accounts for close to 40 percent of the

hazardous waste collected by DCS every year.8 F003 includes spent non-halogenated solvents

such as acetone and cyclohexanone.

F003 chemicals are an active ingredient in many cleaning products and solvents. While

Barnard Facilities uses Green Seal cleaning products for daily maintenance, it is possible that

certain non-conventional cleaners on campus (i.e., paint remover) still contain these substances.

Thus, it is recommended that Barnard limit the purchase and use of hazardous cleaning solvents

as much as possible. Although non-hazardous cleaning alternatives are usually more expensive

than their toxic counterparts, the increased cost is partially offset by the savings on contracted

disposal and benefits to public health.

Acid Wastewater

When pre-treated, some moderately corrosive laboratory chemicals can be discharged

into the sewer system. Therefore, each laboratory in Altschul Hall contains one or more sinks

connected to a separate drain system used solely for the disposal and treatment of hazardous

laboratory wastewater. The glass piping from these sinks lead to four large reaction chambers in

the basement of Altschul. Each chamber contains calcium carbonate [limestone], which is


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capable of neutralizing wastewater of moderate acidity. As caustic water passes through the

tanks, acidic components react with the calcium carbonate to form harmless neutral salts, carbon

dioxide, and water.9 The neutral salts precipitate into sludge and settle at the bottom of the

neutralization tanks, while the treated wastewater is discharged into the NYC combined sewer

system.

Optimal operation of this system is crucial to minimizing Barnard’s negative impact on

the NYC sewage treatment system. Improper discharge of corrosive chemicals can damage the

sewer as well as the environment. If untreated, the chemicals have the potential to corrode both

concrete and metal sewer pipes. Corrosive wastewater also alters biological oxygen demand,

which is detrimental to the vital bacteria used in sewage treatment plants.

Barnard’s acid wastewater treatment system is inspected every two months by Acid

Waste Management. Every year this contractor replaces the limestone medium in the tanks and

removes accumulated sludge. Barnard Facilities states that maintenance, such as the replacement

of leaky gaskets or pipes, is performed on an as-needed basis. However, a brief visit to the tanks

indicated that the system is in questionable condition [see Appendix F]. We observed a leaking

pipe, and many of the pipes leading into the neutralization tanks appeared to have been

previously repaired with large amounts of duct tape. The Initial Sustainability Report suggests

that Facilities inspect water pipes for leaks regularly, but does not specifically mention the acid

wastewater treatment system.10

On-site neutralization of laboratory wastewater has several advantages. It is cheaper and

easier than collecting laboratory wastewater in separate containers, storing the containers, and

paying a contractor for collection and disposal. In addition to the practical benefits, the system


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has a relatively minimal environmental impact; it requires no electricity and uses a long-lasting

neutralizing medium.

While the current on-site treatment approach has positive aspects, neither Barnard

Facilities nor Acid Waste Management monitor the corrosiveness of discharged water. It is

simply assumed that the tanks increase the pH of the acid waste to an acceptable level11 for

disposal to the NYC sewer system. Continued testing of the treated water would make known the

efficacy of the on-site system. Our primary acid waste recommendation is for a routine analysis

to be conducted on the treated wastewater. At a very minimum, a simple and inexpensive pH test

should be used. If financially feasible, we recommend an advanced analysis of the composition

of the water, which would detect if untreatable chemicals had been introduced into the system.

Finally, it is suggested that Barnard procure the services of an independent company for the

purposes of evaluating the condition of the current system, based on the possible disrepair that

was observed.

Gray Water

Using large volumes of water increases maintenance and lifecycle costs for building

operations and increases consumer costs for municipal supply and sewage treatment facilities.

Therefore, it benefits both people and the environment to reduce water consumption. According

to some estimates, water efficiency measures in commercial buildings can easily reduce

consumption by 30 percent or more. In a typical 100,000-square-foot office building, low-flow

fixtures coupled with sensors and automatic controls can save at least one million gallons of

water per year. In addition, non-potable water can be used for irrigation as well as toilet and

urinal flushing. The resulting utility savings adds up to thousands of dollars per year, leading to


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rapid return on the investment in a retrofitted water conservation infrastructure. Installing a gray

water system is pivotal to Barnard’s effort to minimize its contribution NYC CSOs.

Gray water consists of untreated wastewater from bathrooms, showers, washing machines,

and other building activities that do not involve human waste or food processing. Wastewater

from kitchen sinks, dishwashers, and the washing of material soiled with excrement is referred to

as black water. When handled properly, gray water is a safe solution for reduced water output.

The Energy Policy Act of 1992 established water conservation standards for restrooms,

shower heads, faucets, and other uses to save the United States an estimated 6.5 billion gallons of

water per day. While this act is a good starting point, there are many other ways to exceed this

standard and achieve even greater water savings. Effective methods of reducing potable water

use include reusing roof runoff for non-potable applications, using gray water from bathroom

sinks and showers to flush toilets, collecting rainfall in onsite cisterns, and water-efficient

landscape irrigation.

The New York State Department of Environmental Conservation [DEC] and Department

of Health [DOH] have not developed extensive guidelines or regulations for wastewater reuse.

Each proposed project is considered by DEC and DOH on an individual basis. For specific

legislation and details, refer to Appendix A.

Water use strategies depend on site location and site design. The following are

approaches that implement gray water technology towards improving Barnard’s water

management:

• Develop a water use inventory that includes all water-consuming fixtures, equipment,

and seasonal conditions to identify significant potable water demands and determine

methods to minimize or eliminate these demands.


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• Develop a wastewater inventory and determine areas where gray water can be used

for functions that are conventionally served by potable water. These should include

sinks, showers, toilets, irrigation, and maintenance applications.

• Consider installing a roof or in-ground water collection system. Use metal, clay, or

concrete-based roofing materials and take advantage of gravity flows whenever

possible.

Industrial gray water equipment, however, is expensive because the process includes

collection, filtration of large objects (i.e. leaves, branches, stones, etc.), and storing rainwater. In

addition, a gray water system must be coupled to the existing piping infrastructure that is

connected to the sewer system in order to prevent malfunction in the event of empty or

overflowing holding tanks.

Reusing gray water for domestic applications such as toilet flushing and floor washing is

more complicated because gray water systems must be in compliance with existing strict

domestic public health regulations. It is therefore essential to plan gray water systems in the

context of large collective installations with a high number of flushes and significant floor

surfaces. Thus, Barnard is a prime candidate.

Considering the benefits associated with water conservation and reduced institutional

CSO contribution, rainwater reuse is potentially the most sustainable strategy. In terms of

impact on downstream infrastructures, rainwater reuse from roof runoff for toilet flushing proves

to be more efficient than other water conservation strategies. The characteristics and location of

existing buildings also heavily influence the necessity and feasibility of water reuse strategies.

Wastewater treatment and water recovery systems involve significant initial investments

and require maintenance over the building's lifetime. Nevertheless, gray water systems can lead


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to lower water bills when water is metered. Thus, these installation and maintenance costs

balance with the anticipated savings in water and sewer bills. Although this may not appear

immediately relevant to Barnard’s current situation because water bills are mostly based on

frontage and not on the actual quantity of water used, this might change in the long run as the

City moves towards required metering.

Finally, saving water also saves energy since electricity and fossil fuels are consumed

each time water is moved or treated. Water related energy use includes conveyance, storage,

purification, distribution, and wastewater treatment. In accordance with the mandate of the Initial

Sustainability Report and Academic Services Committee, grey water systems can be a major

vehicle towards greatly reducing Barnard’s carbon footprint.

Water Holding Tanks and the Use of Steam Power

While water conservation is an important issue on Barnard’s campus, NYC’s tremendous

abundance of clean fresh water makes water conservation less of a priority than in drought-prone

environments. Even if this is not considered an immediate concern, the unnecessary overuse of

water contributes to NYC’s problem of CSOs.

After conducting an initial ground truth survey on Barnard’s campus, it was determined

that Barnard has sufficient rooftop space for the placement of at least one water holding tank.

These could be placed on the rooftops of Barnard Hall, Lehman Library, and Altschul [see

Appendix C]. While we have mentioned the use of open roof space for greenroofs [see below for

details], water holding tanks could be used in conjunction with the greenroof plan to further

decrease Barnard’s contribution to CSOs.


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As aforementioned, Barnard could implement a system throughout campus that could

collect and pump water into holding tanks to be used in a variety of ways. Perhaps a more useful

way of using this gray water is for the operation of steam power. Steam power is a clean, easy to

maintain, and energy efficient way of providing heat to Barnard’s campus.

According to the Initial Sustainability Report, all buildings on campus except Elliot

contain dual-fuel boiler units capable of burning either oil or natural gas.17 The retrofitting of a

steam power system in several areas around campus would reduce the use of oil or natural gas on

campus and thus decrease Barnard’s dependence on dirty energy sources. Water is a much

cheaper and accessible means of heating and cooling Barnard’s buildings than an oil and gas

powered system. By innovatively reusing a free and clean resource, Barnard would save money

and, more importantly, reduce its energy consumption and contribution to NYC CSOs.

Figure 4. Greenroof Structure


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Greenroofs

As discussed above, combined sewer overflow is responsible for the discharge of more

than 27 billion gallons of raw sewage and polluted storm water into the New York Harbor each

year. Herein lies an opportunity for Barnard to be a beacon of light for sustainable practice, and

to inspire our community to follow suit. The College has demonstrated its commitment to

sustainable ideals in a few ways, especially in the eco-friendly elements of the Nexus

development, which includes the installation of a vegetated rooftop.

As noted, greenroofs offer a rare opportunity for urban environments to alleviate the

impact of rainfall on the sewer system. The benefits are measurable, and include aesthetic,

ecological, economic and psychological gains. Greenroofs are vegetated roof covers that feature

several layers of matting topped with growing media and plants in place of bare rooftop [see

Figure 4]. Sedum plants can survive long periods of drought, heavy rainstorms, and severe

winds, and require minimal maintenance following the initial installation. For these reasons,

Barnard should endeavor to install greenroof systems atop as many existing buildings on campus

as possible.

Moreover, greenroofs help to combat the “urban heat island” effect, which is particularly

severe in NYC. They function to reduce ambient air temperatures and increase humidity levels as

precipitation is collected and evaporated back into the atmosphere. Greenroofs also help to

process pollution from this precipitation. Additionally, they filter and bind dust particles and

airborne toxins, helping to improve urban air quality. Greenroofs also embody both physical and

culturally sustainable design concepts and are often constructed using components made from

recycled materials.


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With average runoff absorption rates of 50 - 60 percent, a large greenroof installation on

campus could significantly reduce Barnard’s CSO contribution during storms. One such option is

the 10,000 square foot Lehman Library rooftop which is one of the largest rooftop surfaces on

campus. This building, along with all the others, currently drains water directly from the rooftop

into the city sewer system.

Dr. Paul Mankiewicz, Gaia Institute executive director and board member of the New

York City Soil & Water Conservation District, states:

Each 10,000-sq-ft green roof can capture between 6,000 and 12,000 gallons of

water in each storm event. This is rainfall that will never enter the combined

sewer. At the same time, the evaporation of this rainfall will produce the

equivalent of between 1,000 and 2,000 tons of air conditioning--enough heat

removal to noticeably cool 10 acres of the city. This is a management practice

that increases biodiversity and can literally add enjoyable landscape to all the

boroughs of New York.

Greenroofs can offer more tangible benefits to the buildings as well. The life of existing

roofing is extended because greenroofs shield against the effects of UV radiation, temperature

extremes, and mechanical damage. The natural thermal insulation properties of the materials also

enable structures to stay cooler in summer and warmer in winter. This can significantly reduce

costs for the building, and could help Barnard to achieve its pledge of reducing energy usage and

cutting carbon emissions by 30 percent by 2017. As with other suggestions thus far, installation

costs are ultimately offset through long term energy and maintenance savings.

In New York City, the average cost of greenroof installation is approximately $18 - 20

per square foot [including labor]. It is reasonable to expect that Barnard will be able to negotiate

cheaper pricing for a large-scale contract, especially as a non-profit institution. Additionally, the

City has recently launched a greenroof initiative offering property tax credits in the amount of

$4.50 per square foot, up to $100,000, for those who install greenroofs covering 50 percent or


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more of their available rooftop space. Were the College to move forward with a large scale

project to install greenroofs on campus buildings, this credit could potentially be used to recover

up to 25 percent of the installation cost. It is highly recommended that Barnard seriously pursue

such infrastructure changes.


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Conclusion

Water conservation and CSO reduction are imperative to diminish Barnard’s contribution

to the 27 billion gallons of raw sewage and dirty storm water that pollute the Hudson River and

New York Harbor each year. As a responsible institution, Barnard has both a public and moral

obligation to implement a definitive plan expeditiously to facilitate the recommended changes

within a sensible timeframe. It is recommended that the Academic Services Committee in

conjunction with Barnard Office of Facilities create change in the following sequence:

• Community education highlighting personal responsibility for water reduction

• Voluntary installation of water metering for all Barnard buildings

• Installation of high efficiency/low-flow appliances & fixtures where possible

• Rerouting of storm water runoff through permeable pavers, greenroofs, and holding

tanks

In the future, gray water systems and steam heating should be implemented as additional

measures.

There are challenges that may impede immediate change. These include, but are not

limited to: time constraints; the current economic situation; finding available space without

requiring major renovation; sustained motivation from the upper levels of Barnard administration;

and finally, the public notion that City residents do not consider water as limited a resource as in

a drought prone region. It is vital that the College takes responsibility for the total environmental

impact of its community members.

Although the collective recommendations contained in this report require significant

resources, small steps are the way to begin the process. The changes advocated here have both

public and financial incentives. Barnard would increase its recognition as a leading green

college, would engender public goodwill, and become a guiding light for schools around the

nation who wish to be environmentally responsible. We acknowledge that many of these


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changes require substantial initial funding however, the costs are likely to be recovered in tax

rebates and savings on utility bills. The infrastructure modifications should pay for themselves

within several years.

In the past the Environmental Protection Agency [EPA] has mandated that taxpayers fund

the cleanup of damaged waterways. The historic examples of Narragansett Bay, Boston Harbor,

and the Charles River have proved that such projects can be successful with appropriate

leadership and public investment. It is only a matter of time before the EPA requires New York

City to restructure its wastewater management system. Therefore, it behooves Barnard College

to be ahead and proactively involved in this process before it is forced to change. We

recommend that the Academic Services Committee of Barnard College effect the delineated

changes as rapidly as possible.


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References 1 Plumb, Mike and Basin Seggos. Sustainable Raindrops: Cleaning New York Harbor by Greening the Urban Landscape. Report for Riverkeeper® Fall 2008. http://www.riverkeeper.org/special/Sustainable_Raindrops_FINAL_2008-01-08.pdf

2 Jeng-Chung Chen, Ni-Bin Chang, Chiee-Young Chen, and Chiu-Shia Fen. Minimizing the Ecological Risk of Combined-Sewer Overflows in an Urban River System by a System-Based Approach. J. Envir. Engrg. 130 (10). p. 1154-1169, 2004.

3 DC Water and Sewer Authority. (DC WASA) http://www.dcwasa.com/images/csohom6.gif Date Accessed: December 11, 2008. 4 Dan Davis, Assistant Director of Barnard Facilities 5 2007 Initial Sustainability Report, 20 6 Vrijheid M. Health effects of residence near hazardous waste landfill sites: a review of epidemiologic literature. Environ Health Perspect. 2000; 108(Suppl 1):101–112. 7 40 CFR § 261.31 8 Dan Davis, “30% - %40” 9 “On-site Neutralization of Laboratory Wastewater: Northern Territory University” Northern Territory Chamber of Commerce and Industry Pub. Feb 1997, available at http://www.environmental-expert.com/resultEachArticle.aspx?cid=19602&codi=1742&idproducttype=6 10 2007 Initial Sustainability Report, 24 11 New York City requires “normal sewage” to have a pH between 5.0 and 9.5 (New York City Administrative Code § 24-523.10) but this requirement varies for different customers (such as industrial users). 12 2007 Barnard Sustainability Report, http://www.barnard.columbia.edu/about/green/ISR_9_08.pdf P.25


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Appendix A. New York State Environmental Law – Title 6 – Article 15

15-0601

1. "Water reclamation project" means a project designed to utilize reclaimed wastewater or grey water for beneficial non-potable uses including, but not limited to, agricultural and landscape irrigation, commercial and industrial uses, and wetland maintenance purposes. 2. "Grey water" means untreated wastewater from bathtubs, showers, washing machines, dishwashers and sinks, but shall not include discharges from toilets or urinals or industrial discharges. 3. "Reclaimed wastewater" means water discharged from a treatment works utilizing at least effective secondary treatment

15-0603

1. The department, in consultation with the department of health, shall conduct a study of potential uses of grey water and reclaimed wastewater in New York State, and develop a strategy for promoting water reclamation projects. 2. Such study shall be completed within eighteen months of the effective date of this section and a report of the findings from the study shall be presented to the governor, the speaker of the assembly and the temporary president of the senate within ninety days of the completion of the study.

15-0605 Standards for reuse and disposal of reclaimed wastewater

The commissioner, in consultation with the department of health, shall establish rules, regulations and standards for the reuse and disposal of reclaimed wastewater and/or grey water. The department of health shall advise the department on water quality and pathogens monitoring requirements. 1. Such rules, regulations and standards shall specify: a. The permitted uses of reclaimed wastewater and grey water with required levels of water quality and treatment for each permitted use; permitted uses shall include, but not be limited to: industrial cooling; commercial and industrial landscaping; park and golf course irrigation; groundwater recharge; surface water supply augmentation; wetland creation and augmentation, and non-food agricultural crop and lawn irrigation. b. Operational requirements including, but not limited to, treatment facility reliability; storage requirements, if necessary; system labeling and color-coding requirements; and pipe location and placement. 2. Such rules, regulations and standards shall be promulgated within thirty months of the effective date of this section.

15-0607 Utilization of reclaimed wastewater registry All persons utilizing reclaimed wastewater or grey water shall register such project with the department. The department shall maintain such registry.


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Appendix B. Current Roof Run Off at Barnard

Figure 1. Drain on roof of Altschul Hall. This drains storm water directly from the roof of Altschul Hall into

the sewer system.

Figure 2. Downspout from Altschul Hall.

Figure 3. Downspout from Altschul Hall [continuous flow from Fig. 2].


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Figure 4. Drain from roof of Altschul Hall to sewer. [This is the bottom of the downspout seen in Fig. 2]


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Appendix C. Possible Greenroof sites at Barnard

Figure 1. Image of a greenroof [not at Barnard]

Figure 2. Image of a greenroof [not at Barnard]


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Figure 3. Nexus building roof will be a greenroof.

Figure 4. Roof of Altschul Hall


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Figure 5. Possible greenroof locations on Claremont Avenue [Elliott Hall].

Figure 6. Additional greenroof space on Claremont Avenue

Figure 7. Possible greenroof location on Barnard Hall.


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Figure 8. Possible greenroof space on Lehman Hall.

Figure 9. Possible greenroof space on Lehman Hall


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Figure 11. Possible greenroof space


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Appendix D. Plimpton Dormitory Case Study

Plimpton is a metered property and the water that is used is charged at $2.31/748 gallons

multiplied by a 159% sewer charge. This equates to a $3.673/748 gallons of water used. The

majority of the fixtures found in Plimpton are high flow, 3.5 gallon toilets [Figure 1] and 2.2

gallons per minute shower heads [Figure 2]. Replacing these fixtures with more efficient ones

will save an estimated 2.25 million gallons of water or around $11,000 annually between

showerheads and toilets alone [using daily estimates and 365 days of use]. Other fixtures like

top end washers [Figure 4], which use nearly double the water of front loading washers could

save additional money. Under a metered water system, a direct savings is realized when water is

saved, unlike in a frontage system. Low cost solutions include replacing showerheads or capping

sinks to slow the flow of water per minute.

Figure 1. 3.5 gallon Toilet in Plimpton suite


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Figure 2 2.2 gallon per minute shower head in Plimpton suite

Figure 3. Some fixtures are low flow, however dual handle flush system could be added

Figure 4. Top loading washers use nearly twice as much water has front-loading washers


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Figure 5. Wastewater from washers goes directly into the sewer from the sink

Figure 6. The white box is an easy access meter for NYC DEP

Calculations:

$2.31 Water Charge / 748 gallons *1.59 Sewer charge 56 Residential Toilets – 17.5 gallons/person/day 4900 gallons/building/day $3.673/ 748 gallons $24.06/building/day Toilet Water Bill—$8781.90/year *Based on 1:4 solid/ liquid usage using a 3.5 gal/13 liter toilet for 5 flushes/person/day Sloan Uppercut handle—1.6/1.1gpf 6 gallons/person/day 1680gallons/building/day $3.673/ 748 gallons $8.26/building/day Total Reduced Toilet Water Bill—$3014.90


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Based on 1:4 solid/ liquid usage using a 1.6/1.1gpf Sloan uppercut handle w/ 5 flushes/person/day 56 Shower Heads— 2.2gpm 22gallons/person/day 6160gallons/building/day $3.673/748 gallons $30.27/building/day Shower Water Bill--$11048.55 *Based on 10min shower/person/day w/ 2.2gpm spout 1.5gpm 15 gallons/person/day 4200gallons/building/day $3.673/748 gallons $15.72/building/day Reduced Shower Water Bill--$5737.80 *Based on 10min shower/person/day w/ 1.5pgm spout Today’s Fixtures-----$19830.45 Reduced Fixtures-- $8752.70 Savings---$11077.75(365 days of use) (2.25 million gallons of water) Other Recommendations

• Low Flow Washers

• Low Flow Sinks


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Appendix E. Water and Energy Efficient Fixtures & Appliances

Figure 1. Water-saving showerhead.

Figure 2. Solar Water Heater.

Figure 3. Solar Water Heater (Alternate Model).


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Figure 4. Water Meter.

Figure 5. Waterless urinal, Sloan model# WES-2000

Figure 6. Automatic-sensor Toilet.


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Figure 7. Push Toilet.

Figure 8. Dual flush toilet valve

Figure 9. Top-loading laundry machines

Figure 10. Concentrated detergent dispenser


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Figure 11. Green Seal Cleaning Products.

Figure 12. ECOLAB concentrated cleaner


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Appendix F. Miscellaneous

Figure 1. Acid tanks

Figure 2. Fresh leak stain near acid tanks.


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Figure 3. Pipes in need of repair, Altshul basement

Figure 4. Altschul HVAC Roof Unit Underbelly


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Figure 5. Irrigation lines and pavers in front of Lehman Library

Figure 6. Sprinkler head

liquid waste report

Documents

barnard college fall

barnard college practices

wastewater management

barnard campus

fresh water

potable water

sustainable water conservation

polluted storm water