CEE171 Final Project

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Table of Contents

Section Title Page Number

1. Executive Summary……………………………………………………………………………………………….. 3

2. Introduction…………………………………………………………………………………………………..……... 4

3. Design Layout………………………………………………………………………………………………….…….. 6

3.1. Commercial Area…………………………………………………………………………………....... 6

3.2. Open Space……………………………………………………………………………………….…….... 6

3.3. Residential Area……..…………………………………………………………………….…...……... 6

3.4. Constraints……………………………………………………………………………………………...... 7

3.5. Alternative Options………………………………………………………………………….…….….. 7

4. Water Distribution System……………………………………………………………………………………... 9

4.1. System Design………………………………………………………………………………….………... 9

4.2. Demands and Requirements…………………………………………………………..……….… 9

4.3. Pump Specifications……………………………………………………………………………..…... 11

4.4. Cost Analysis………………………………………………………………………………………........ 11

5. Stormwater Management System…………………………………………………………………………. 12

5.1. System Design…………………………………………………………………………………….….... 12

5.2. A 25-Year Storm…………………………………………………………………………………..…... 12

5.3. Low Impact Design………………………………………………………………………………….... 13

5.4. SWMM Analysis with LID Implementation……………………………………………..…. 15

6. Appendix……………………………………………………………………………………….………………….…... 16

6.1. Tables and Figures……………………………………………………………………………….….... 16

6.2. Sample Calculations………………………………………………………..………………...……... 27

6.3. References……………………………………………………………………………………...…..……. 28

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Section 1: Executive Summary

The city of Tustin, California would like to develop a three hundred thirty acre plot of land with a

layout that includes residential, commercial, and recreational areas, as well as open space. The location

of this development was originally the Tustin Marine Corps Air Station. The community is located

between the busy streets of Jamboree Road and Edinger Avenue near the Tustin Legacy shopping

district.

The three hundred thirty acre plot of land is divided into approximately eighty acres of

commercial space, one hundred fifty acres of residential space, and one hundred five acres of

recreational space and open land. The commercial area contains two large stores, fifty medium

businesses, and thirty restaurants. The residential area is divided into one hundred ninety low end

housing units, eighty high end housing units, and one hundred thirty-five apartment units. The open

land section of the community consists of hiking trails, a nature preserve, a rainfall collection reservoir, a

water storage tower, and a fifteen-acre community park.

The water distribution system for the community is able to deliver sufficient water supply while

reducing the daily peak demands and minimizing cost. In order to do this, a rainfall reservoir will be

implemented to store rainwater runoff, and a pump will aid in increasing water flow and pressure. The

overall estimated cost of installing the pump system is $1,498,249.85 with a charge of $98.24 per day for

electricity to run the pump.

The stormwater management system is designed to handle a 25-year storm, or a storm with a

four percent chance of happening. The community is divided into seven different rainfall

subcatchments. A one-foot diameter conduit collects the water from each subcatchment and runs to

one main junction that leads to the outfall along Peters Canyon Wash. Low Impact Design methods

were implemented in order to reduce the total runoff of the system at a total cost of $18,128,670.00.

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Section 2: Introduction

The area of interest for the team design project is located at the Tustin Marine Corps Air Station

within the city of Tustin, California. This area, shown in Figure 2.1 in the appendix, is approximately half

a square mile, or three hundred thirty acres. The objective of the design project is to develop a new

community and minimize the daily peak water demand, installation, operation costs, stormwater runoff,

and environmental impact while maximizing long-term sustainability of the area’s water resources. The

community must include at least four hundred mixed-income units to house an estimated 1,250 people.

Development plans for recreational and commercial zones are also required. At least thirty percent of

the land must be undeveloped; street layouts must also be included in design plans. The surrounding

area of the site, as well as site elevation, and soil composition must be taken into account when

planning the community. A detailed description of the community layout can be found in section three

of the report.

Water supply for the community comes from a main on Edinger Avenue, which runs along the

eastern edge of the community. Only one water supply connection to the community is permitted from

the main. The pressure in the main must stay within the range of eighty to one hundred pounds per

square inch at all times. The water distribution system must be able to deliver the minimum amount of

water needed for daily domestic and firefighting activity. Adding a pump to the system in order to meet

demands is permitted, but the pump must be modeled after a prototype supplied by the manufacturer.

Cost estimates for the water distribution system were provided by the pump manufacturer,

Construction Company, and Southern California Edison Electricity Company. The water distribution

system as well as cost analysis for the system are discussed in detail in section four of this report.

Rainfall in the community must lead to one outfall along Peters Canyon Wash, which is located

near the south-east corner of the community. A stormwater collection and retention system for the

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community must be designed under the conditions of a 25-year storm event. All data provided for a 25-

year storm was taken from the 1986 Orange County Hydrology Manual. Only gravity is used to move the

water in the system through the conduits. Not only is the design team responsible for creating a system

that ensures no increase in site runoff, but also the design team must decrease the amount of site

runoff by implementing low impact designs. These low-impact designs will be implemented to help

reduce the environmental impact of the entire system. Since no cost estimates for the stormwater

system are provided, it is up to the city of Tustin to determine the total cost of the conduit installation. A

detailed description of the stormwater collection, retention system, and low impact designs can be

found in section five of this report.

Throughout the design process, the team strived to come up with new and creative ideas. With

several goals to keep in mind throughout the process, the team found that simplicity was the most

effective method in accomplishing these goals. The remainder of this report goes into detail explaining

exactly how all of the design team’s ideas were implemented to comply with the research done in the

project.

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Section 3: Design Layout

See Figure 3.1 in the Appendix for the AutoCAD drawing of the community layout.

3.1 Commercial Area

The eighty acre commercial zone, which takes up twenty-four percent of the total land, is

located strategically in the south-west portion of the community in order to expand the already existing

commercial area known as the The District at Tustin Legacy. Developing the commercial area in this

section of the community allows for the area to stay consistent. It allows for residents to not have to be

surrounded by noisy commercial businesses. The area is divided into two large retail stores, fifty

medium level businesses, and thirty restaurants for patrons to enjoy. This area also provides ample

parking space to accommodate the large amount of cars entering the shopping center on a daily basis.

3.2 Open Space

The open space zones offer outdoor activities for the patrons of the community to enjoy. The

open space is composed of one hundred five acres of land covering thirty-one percent of the parcel. The

area is positioned along the south-east border of the community to act as a noise barrier from Jamboree

Road. This area is different from the rest of the zones in the fact that it is not going to be developed.

Hiking trails will be created and natural vegetation will be allowed to grow. The community water

storage tower as well as the rainfall reservoir basin will also be on this parcel. Another section of open

area in the community is the fifteen acre park located near the apartment complex. The park will

provide residents with recreational facilities such as sports fields, a community center, playgrounds, and

barbeque areas. Greenery will be planted on the border of the park to preserve its natural state and to

block noise pollution from outside traffic.

3.3 Residential Area

The high density housing area is located on the north-east part of the community. This portion

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of housing consists of one hundred thirty-five apartment units, which are built closest to Jamboree

Road. Short one way streets are developed in the apartment complex to easily allow residents to reach

the park.

Medium density housing is located in the northern section of the design layout. This area

consists of one hundred ninety houses. Residents are provided with more privacy in comparison to the

high density housing units. The area contains two-way streets with twelve-foot roadways and six-foot

sidewalks. Larger roads are implemented in this housing area to assure safe play for children. Residents

in this community have easy access to Tustin Ranch Road.

Low density housing is located in the northernmost corner of the community. This area is

strategically placed farthest away from Jamboree road so that residents have a quiet living experience.

The eighty houses in this area are the largest of all the residential areas. Since the low density housing

area is the most desirable, it will contain the most expensive housing units.

3.4 Constraints

It was required that open spaces, including recreational areas, must cover at least thirty percent

of the parcel. Also, the community needed to have at least four hundred housing units and house at

least 1,250 people. Other factors that were considered during development were: the existing roads,

soil type, elevation of the land, and the history of the land, to determine if any environmental permits

are needed.

3.5 Alternative Options

To prove the feasibility of the proposed plan for the Tustin Marine Corps Air Station the design

team evaluated several alternatives. In regards to the design layout, another idea that was considered

was having a large central park at the epicenter of the zone modeled after Aldrich Park. The housing

units would then be developed along the border of the park. This would help unify the residents within

the area. Another alternative idea was having a hospital and a police and fire station in the area to

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provide extra protection for residents. The final alternative considered was having a multi-story parking

lot near the commercial zone in order to minimize the amount of lot space needed for parking.

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Section 4: Water Distribution System

4.1 System Design

The community water distribution system was modeled using EPANET 2.0 based on the

AutoCAD layout of the proposed design. A picture of the model, Figure 4.1, can be found in the

appendix. The distribution system pipes were designed to run underneath the streets surrounding each

of the five different community zones with a connection at each zone corner. There are also pipes and

connections running underneath the streets through each zone. The system is made entirely of closed

loops since the pipes are made of flexible material PEX (discussed in Section 4.4). A fire hydrant is

placed every five-hundred feet throughout the system in order to assure maximum safety in the event

of a fire (Lamm). The system was designed using minimal amount of pipes needed to help keep costs

relatively low.

4.2 Demand and Requirements

Each of the five different community zones have different water demands. For each different

zone, the total amount of water used per day was divided between the number of connections

surrounding the zone to ensure that the water demand was constant throughout. These values were

converted to gallons per minute and used as the base demand to input into each node in EPANET. All

water demand values can be found in Table 4.2 in the appendix.

One of the design team’s main goals in creating the water distribution system was to reduce the

daily peak demand of the community while making sure that the system was still able to deliver

sufficient water supply. The commercial zone, which consists of two large stores, fifty medium size

businesses, and thirty restaurants, is the zone with the highest demand of 86,200 gallons per day

(Hickey). Even though the commercial zone is an expansion of the Tustin Legacy shopping district, its

water supply comes completely from the new water distribution system. The toughest task was to

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determine how to get enough water to the zone without increasing total cost. This is why the rainfall

collection reservoir is conveniently located just east of the commercial zone. During peak hours, extra

water gets delivered to the zone from the reservoir so that the pump speed never has to increase and

water pressure in the other communities does not decrease.

Recreational water demand was found by researching parks approximately the same size as the

one in the community design. It was found that parks around fifteen acres in size use about 56,580

gallons of water per day (Leal, Mendoza). The pump for the distribution system was conveniently placed

near the community park which requires the second-most amount of water per day. This helps ensure

that this part of the community constantly receives adequate water supply. Water used in the sprinkler

system to keep the nature trail preserved is taken from the reservoir basin. This means that this demand

was not included in the total system water demand. The water demand of the residential zones were

derived from the fact that the average person uses about one-hundred gallons of water per day in

domestic activities (“Indoor Water Use”). The average number of people per household for each type of

housing was then used to calculate the total amount of water used per day.

Firefighting water demand was also taken into account when designing the system. The

minimum amount of flow needed to fight fires at one instance is 500 gallons per minute for two hours.

The maximum flow needed is 12,000 gallons per minute for four hours. This means that there needs to

be between 60,000 and 2,880,000 gallons ready at all times (Hickey). This is why the system storage tank

can hold 3,000,000 gallons of water. It was demanded that the pressure in the connection to the Edinger

Avenue water main be between eighty and one hundred pounds per square inch at all times. The tank

dimensions were adjusted accordingly with the volume so that this level of pressure is always

maintained.

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4.3 Pump Specifications

Since there was a very minimal elevation change throughout the community, a pump was

needed in order to maintain high flow rates throughout all the pipes in the system. The type of pump

used is a dynamic centrifugal pump because relatively low pressure is needed at the water main

connection, and a high, steady flow rate is needed throughout the entire system. The pump head curve

is scaled based on a small model provided by the manufacturer. The real pump has an impeller diameter

of thirty inches and runs at a constant rate of 1200 revolutions per minute. A graph of the pump head

curve, Figure 4.3, can be found in the appendix.

4.4 Cost Analysis

Another main goal of the design team was to keep costs as low as possible. All water distribution

system costs can be viewed in Table 4.4 in the appendix. Since piping installation cost increases greatly

with increasing diameter, cost is reduced by keeping the diameter of the piping system small. The

diameter used is eight inches for all pipes in the system. The piping material used was Cross-linked

Polyethylene (PEX) and cost efficiency is one of its many benefits. Using this material saves money over

a long period of time because very low maintenance is required. PEX does not experience any corrosion

and has an estimated lifespan of 50 years (Heavens). PEX also allows for high node pressures since it is

flexible. It can make over ninety degree turns so fewer connections are needed (Heavens).

Also, the particular pump specification used will save money in the long run. Pump purchase and

installation cost is a one-time fee, but electricity is charged per day. While having a large impeller size

will increase the purchase and installation cost of the pump, it will allow for a lower pump speed, which

is more energy efficient and cost effective over a long period of time.

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Section 5: Storm Water Collection and Retention System

5.1 System Design

The stormwater management system was modeled using EPA SWMM 5.0, shown in Figure 5.1 in

the appendix. The community was divided into seven regions called subcatchments. Each one

represents an area with a different percentage of imperviousness. The greater the imperviousness, the

less the land is able to store water. Percent imperviousness was found by dividing the area of

impervious objects on a parcel of land by the total area of that parcel. This is why the commercial zone is

divided into three smaller subcatchments instead of one large one. Different sections vary greatly in

imperviousness from forty to eighty percent. If the commercial zone had been left as one subcatchment,

the runoff depth into the conduit would exceed the diameter of the pipe and result in flooding.

In the design, the conduits are circular with a one-foot diameter and are made of smooth

concrete. This material was chosen because it is highly cost effective compared to other alternatives

such as plastic and steel. Smooth concrete is a more durable and sustainable, as it continues to function

with a long life span, thus reducing the costs for repair and replacement. (“Why Concrete Pipe?”) A total

of eight conduits make up the stormwater management system, resulting in a total length of 8,800.62

feet of piping. Rainfall flows from a subcatchment to a conduit and each conduit connects at a junction

that leads to the main system outflow. The system is driven by gravity since the elevation throughout

the land ranges from around forty to fifty feet with a minimal change in slope.

5.2 A 25-Year Storm

A 25-year storm is a flood event that has the probability of a four percent chance of occurring in

a given year. The data for a 25-year storm was compiled using the 1986 Orange County Hydrology

Manual. The compiled data was used to simulate a three hour storm event in SWMM. Only three hours

of rainfall data were needed since the total area of the community is relatively small. Table 5.2 and

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Figure 5.2 in the appendix show the specific rainfall data that was inputted into SWMM.

5.3 Low Impact Design

Low Impact Design (LID) is a land development practice that sustainably manages stormwater

runoff as close to the source as possible (“Low Impact Development”). This minimizes the overall impact

on the environment and reduces the cost of stormwater collection and treatment. The LIDs that were

implemented were chosen based upon the type of land usage within the area. The five types of LIDs that

were utilized in the subcatchments were bioretention cells, vegetative swales, cisterns, green roofs, and

a detention pond.

Bioretention cells, similar to rain gardens, are depressed areas with vegetation at the surface

(“Stormwater Management Best Practices"). Infiltration occurs at the underdrain providing groundwater

recharge, removal of pollutants, and capture of runoff into the soil. Bioretention cells also act as an

effective stormwater management method in parking lots and urban regions where green vegetative

land is minimal. Within the SWMM model, bioretention cells were placed in the parking lots of the

commercial area, reducing the direct volume capacity on the storm drain system, and lowered the peak

discharge rate. In comparison to the cost and benefit from implementing stormwater conveyance

systems, the cost for residential rain gardens average from $3 to $4 per square foot and $10 to $40 per

square foot for commercial areas. This results in relatively low expenses for installation and an adequate

amount of cost savings in the long run (“Bioretention”).

Vegetative swales are shallow trapezoidal shaped channels with vegetation covering the

surface. They are designed to absorb pollutant particles, facilitate infiltration, and slow stormwater

runoff (“Stormwater Management Best Practices"). Swales are a versatile type of LID and well suited for

residential, industrial, and commercial regions. The cost of vegetative swales are generally inexpensive

and range from $3 to $10 per square foot depending on the complexity of the system (“Bioswales”).

Substantial savings are gained with the use of vegetative swales as opposed to traditional stormwater

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piping systems. With proper maintenance, swales can be aesthetically pleasing and are an

environmentally sound alternative to conventional storm sewers. Vegetative swales were implemented

into the SWMM model on the land bordering the edges alongside the roads, in the vast open space as

prairie grass, and as dense grass in the park area.

A detention pond is an excavated area that provides both retention and treatment of

contaminated stormwater runoff (“Storm Water Technology Fact Sheet”). The physical, biological, and

chemical processes of a detention pond work together to remove pollutants. A wet detention basin was

implemented into the model and designed to be three feet high with a circular area of about two acres,

in order to remain a permanently wet pond. The typical construction costs for a detention pond of one

acre-foot is about $41,600 (“Detention Basin Retrofits and Maintenance”).

A cistern is a storage tank that collects runoff on a rainy day. Unlike rain barrels, which are

normally located outside of each residential unit and smaller in capacity, cistern tanks are larger in

volume and can be installed underground, minimizing above ground land usage. Cisterns are great for

the environment because of their ability to conserve and retain water, which reduces runoff into

stormwater drains and the need for water from a far-off source. This type of LID also reuses the

collected rainwater for the purposes of toilet flushing and gardening. The estimated cost for a small

cistern system ranges between $200 and $600 depending on the material and volume (“Rain Barrel and

Cistern”).

A green roof is a layer of vegetation that grows on top of a roof (“Stormwater Management Best

Practices"). The benefits of green roofs includes reducing energy usage, lowering air pollution and

greenhouse gas emissions, slowing stormwater runoff and filtering pollutants from rainfall, and

providing aesthetics and habitat for species. The cost for vegetative roofs average around $10 per

square foot for extensive roofing and $25 per square foot for intensive roofing with a low annual

maintenance cost of $0.75-$1.50 per square foot. Although the cost for green roofs are higher than

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other materials, the benefits gained eventually offset the installation cost after a period of time (“Green

Roofs”).

5.4 SWMM Analysis with LID Implementation

Based on Figures 5.4.1-5.4.4, it can be observed that with the implementation of low impact

designs, the runoff discharge is decreased significantly. During peak hours, the water depth through

conduit seven is greatly reduced, decreasing from 0.9 to 0.45 feet. Figure 5.4.4 also displays that there is

no flooding at each node throughout the entire system after using LIDs.

The reduction in runoff from the application of low impact designs lowers the cost for

stormwater runoff collection and allows for the number of conduits to remain at the minimum number

of eight for the entire system. By combining all LID materials, the total cost comes to an amount of

$18,128,670. A table displaying the cost for each LID can be found in the appendix under Table 5.4.

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Section 6: Appendix

6.1 Tables and Figures

Figure 2.1: Google Earth image of land to be developed provided by the city of Tustin

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Figure 3.1: community design layout modeled using AutoCAD 2013

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Figure 4.1: water distribution system design modeled using EPANET 2.0

Table 4.2: data calculated for community water demand

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Figure 4.3: water distribution system pump head curve

Table 4.4: water distribution system cost analysis

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Figure 5.1: stormwater management system design modeled using EPA SWMM 5.0

Figure 5.2: bar graph of 25-year storm, 3 hour rainfall intensity

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Table 5.2: 25 year storm intensity data for a 3 hour storm

Table 5.4: low impact design cost analysis

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Figure 5.4.1: node water depth before LID implementation

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Figure 5.4.2: node water depth after LID implementation

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Figure 5.4.3: link water depth before LID implementation

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Figure 5.4.4: link water depth after LID implementation

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5.4.5: no flooding detected throughout entire system with LIDs

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6.2 Sample Calculations

Pipe installation cost Using Pipe #3: 733 ft. in length

C ($/ft.) = 1.3 * [D (in.) ^ 1.5] = 1.3*(8^1.5) = $29.42/foot total cost to install pipe #3 = $29.42/foot * 733 ft. = $21,561.67

Tank storage cost Dimensions: 60 ft. in diameter, 140 ft. tall Volume = [(π/4) * D^2] * H = [(π/4) * (60^2)] * 140 = 395,840.67 ft3

Cost = 52 * (V ^ 0.7) = 52 * (395,840.67^0.7) = $430,792.00

Pump scaling

Q2 = Q1 * [(n2/n1) * (D2/D1)^3] = 45 * [(1200/1760) * (30/5.45)^2] = 929.67 GPM

H2 = H1 * [(n2/n1)^2 * (D2/D1)^2] = 23* [(1200/1760)^2 * (30/5.45)^2] = 323.98 ft. Pump installation cost Impeller: 30 in. Cost = $1500 * D = 1500 * 30 = $45,000.00

Total pump cost = $3,500 + 45,000 = $48,500.00

Energy cost Power = (γ * H * Q)/746 = (62.4 * 929.67 * 323.98)/746 = 25.19 KW

Peak Cost = Power * $0.20 = 25.19 * 0.20 = $5.04/hour (8am - 10pm) Off Peak = Power * $0.11 = 25.19 * 0.11 = $2.77/hour (10pm - 8am) 24 hour energy cost = (5.04 * 14) + (2.77 * 10) = $98.24

Impervious Area (%) (Red, Low Residential Area) Total Area: 3545942 ft2

Road Area: 664662 ft2

Open Land: 1143749 ft2

House Area: 1737531ft2

%Impervious = (Road Area + Open Land + House Area) / Total Area = (664662 ft2 + 1143749 ft2 + 1143749 ft2) / 3545942 ft2 = 0.38 = 38%

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6.3 References

“Bioretention.” Urban Design Tools. lid-stormwater.net. n.p. Web. 15 Mar. 2014. <http://www.lid-stormwater.net/bio_costs.htm>

“Bioswales.” Upper Des Plaines River. n.d. Web. 15 Mar. 2014

<http://www.upperdesplainesriver.org/bioswales.htm>

“Detention Basin Retrofits and Maintenance.” Rutgers Cooperative Extension Water Resources Program. 29 Oct. 2010. Web. 15 Mar. 2014. <http://www.richlandtownship.org/stormwater/RutgersPowerPoint.pdf>

"Green Roofs | Heat Island Effect | US EPA." EPA. Environmental Protection Agency, n.d. Web. 15 Mar. 2014. <http://www.epa.gov/heatisland/mitigation/greenroofs.htm>

Heavens, Alan J. "No cool solution to removing heated tiles." The Philadelphia Inquirer. (2006). Web.

<http://articles.chicagotribune.com/2006-08-11/business/0608110020_1_tile-heating-paint>

Heavens, Alan J. "Shortages Persist In Building Materials: Even as Demand for New Homes Falls, Cost of

Cement and Copper Skyrockets." The Philadelphia Inquirer. (2006). Web.

<http://www.washingtonpost.com/wp-dyn/content/article/2006/07/28/AR2006072800771_pf.html>

Hickey, Harry E., Ph.D. Water Supply Systems and Evaluation Methods. Volume II: Water Supply

Evaluation Methods. U.S. Fire Administration. (2008). Web.

<http://www.usfa.fema.gov/downloads/pdf/publications/Water_Supply_Systems_Volume_II.pdf>

“Indoor Water Use in the United States.” Water Sense: An EPA Partnership Program. U.S. Environmental Protection agency. (2008). Web. <http://www.epa.gov/WaterSense/pubs/indoor.html>

Lamm, Willis. “‘Standard’ Hydrant Spacing.” Designing Water and Hydrant Systems. (2000). Web.

<http://www.firehydrant.org/info/design05.html>

Leal, Jose. Mendoza, Cindy. “Outdoor Water Conservation: Compliance and Costs.” Water Use and

Conservation. California Parks and Recreation: Official Magazine of the California Park and Recreation

Society. Volume 68, Number 2. Spring 2012. Web.

<http://www.migcom.com/files/managed/Document/65/Outdoor_Water_Conservation_CPRS_2012.pd

f>

“Low Impact Development.” EPA. Environmental Protection Agency, n.d. Web. 15 Mar. 2014.

<http://water.epa.gov/polwaste/green/>

"Rain Barrel and Cisterns." Urban Design Tool. lid-stormwater.net. n.p. Web. 15 Mar. 2014. <http://www.lid-stormwater.net/raincist_cost.htm>

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"Stormwater Management Best Practices." EPA. Environmental Protection Agency, n.d. Web. 15 Mar. 2014. <http://www.epa.gov/oaintrnt/stormwater/best_practices.htm#cisterns>

“Storm Water Technology Fact Sheet.” EPA. Environmental Protection Agency, Sept. 1999, Web. 15 Mar. 2014. <http://water.epa.gov/scitech/wastetech/upload/2002_06_28_mtb_wetdtnpn.pdf>

“Why Concrete Pipe?” American Concrete Pipe Association, n.d. Web. 15 Mar. 2014. <http://www.concrete-pipe.org/pages/why.html>

Williamson and Schmid. Orange County Hydrology Manual. Orange County Public Works. (1986). Web. 15 Mar. 2014. <http://ocflood.com/civicax/filebank/blobdload.aspx?BlobID=8336>