rainwater harvesting & condensate recovery (chicago 3.1.12)

Rain Water Harvesting & Condensate RecoveryNew Tools for

Sustainable Site

Development

by

Tom Barrett

Green Water Infrastructure

C o p y r i g h t © 2 0 1 0 b y To m B a r r e t t

Chicago

Green • Water • Infrastructure

Green • Water • Infrastructure

Green • Water • Infrastructure

Green • Water • Infrastructure

Green • Water • Infrastructure

Untapped Reservoir

Untapped Reservoir

Untapped Reservoir

Untapped Reservoir

Untapped Reservoir

How Much Rain Falls in Chicago?

January  -  1.86"February  -  1.58"March -   2.59"April -    3.28"May -    3.75"June-   4.08"July -    3.39"August -    3.38"September -   2.91" October -   2.65"November -  2.09"December -  1.88"Total 33.44"

Image of Rain Falling

Graph of Chicago Rain Fall

Thirty Year Average Monthly Rain Fall

Chicago(1971 - 2000)

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50

5.00

January February March April May June July August September October November December

Month

Inch

es

How Much Water Falls in Chicago?

January  -    2,727 gallonsFebruary  -    2,540March -    4,130April -    5,735May -    5,268June-     5,657July -    5,470August -    7,200September -    5,096 October -     4,223November -     4,691December -    3,787Total     56,525

Image of Rain Falling

2,500 sq. ft. Roof

How Much Water Falls in Chicago?

January  -    11,880 gallonsFebruary  -    11,065March -    17,990April -    24,982May -    22,945June -     24,642July -    23,828August -    31,363September -    22,199 October -     18,397November -     20,434December -    16,496Total     246,221

Image of Rain Falling

¼ Acre Residential Property

How Much Water Falls in Chicago?

January  -    142,560 gallonsFebruary  -    132,784March -    215,876April -    299,783May -    275,344June -     295,710July -    285,934August -    376,358September -    266,383 October -     220,764November -     245,203December -    197,954Total   2,954,654

Image of Rain Falling

3 Acre Commercial Property

How Much Water Falls in Chicago?

January  -    475,195 gallonsFebruary  -    442,610March -    719,581April -    999,267May -    917,805June -     985,690July -    953,105August -  1,254,515September -    887,936 October -     735,873November -     817,335December -    659,842Total   9,848,756

City Block (660’ x 660’ – 10 acres)

How Much Water is in Rain Event?¼” Rain ½” Rain 1” Rain

2,500 ft. sq. Roof

390 gallons 779 gallons 1,558 gallons

¼ Acre Residential Property

1,697 3,994 67,789

3 Acre Commercial Property

20,366 40,731 135,770

Chicago City Block

67,885 135,770 271,540

What can we do with this water?

• Flush Toilets• Wash Vehicles• Clean Sidewalks• Laundry• Water the

Landscape

How Much Do We Use?

DailyMonthly AnnuallyToilet -    19 gallons 570 6,840Bathing -    15 450 5,400Laundry -    8 240 2,880Kitchen -     7 210 2,520Housekeeping -    1 30 360 Total     50 1,500 18,000

The average household uses between 50 and 100 gallons of water per person per day.

How Much Water Does a Landscape Need in Chicago?

January  -    0.00"February  -    0.00"March -    0.68"April -     2.01"May -    3.95"June-   5.89"July -    6.99"August -    6.07"September -    3.87" October -     2.08"November -  0.63"December -     0.00"Total     32.17"

Graph of Chicago Evapotranspiration

Evapotranspiration(Chicago)

-1

0

1

2

3

4

5

6

7

8

Month

inch

es

Evaportation

Graph of Chicago Rain Fall & Evapotranspiration

Precipatation(Chicago)

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

Month

inch

es

Rain Fall

Graph of Chicago Rain Fall & Evapotranspiration

ET vs. Precipatation(Chicgo)

-6

-4

-2

0

2

4

6

8

Month

inch

es Rain Fall

Evaportation

Difference

What is the Problem?

ET Rain DifferenceJanuary  -    0.00" 1.75" 1.75" February  -    0.00" 1.63" 1.63" March -     0.68" 2.65" 1.97" April -     2.01" 3.68" 1.67" May -    3.95" 3.38" -0.57" June-     5.89" 3.63" -2.26"July -    6.99" 3.51" -3.48"August -    6.07" 4.62" -1.45"September -    3.87" 3.27" -0.60"October -     2.08" 2.71" 0.63"November -     0.63" 3.01" 2.38"December -     0.00" 2.43" 2.43"Total     32.17“ 36.27" 4.10"

Landscape Ecology

Size the landscape to the 80% of the average rain water production.

– Roof Runoff

– Hardscape Runoff

Balancing rain water to landscape creates a functional landscape that utilizes the site’s water production.

Stormwater Mitigation

Stormwater Mitigation

Stormwater Mitigation

Stormwater Mitigation

Stormwater Mitigation

Stormwater Mitigation

– Collection runoff near the source

– Slow it down

– Soak it in

– Filter it

– Apply it to the landscape

– Create habitats

Peak Flow(1 Acre Site)

Grass Field Roof

1 Year Storm 1.4 cfs 4.3 cfs

2 Year Storm 2.1 cfs 5.4 cfs

10 Year Storm 4.3 cfs 8.0 cfs25 Year Storm 5.7 cfs 9.5 cfs

100 Year Storm 8.0 cfs 12.0 cfs

cfs – cubic feet per second

Peak Flow(1 Acre Site)

Grass Field Roof

1 Year Storm 10.5 gps 32.2 gps

2 Year Storm 15.7 gps 40.4 gps

10 Year Storm 32.2 gps 59.8 gps25 Year Storm 42.6 gps 71.1 gps

100 Year Storm 59.8 gps 89.8 gps

gps – gallons per second

Peak Flow(1 Acre Site)

Grass Field Roof

1 Year Storm 630 gpm 1,932 gpm

2 Year Storm 942 gpm 2,424 gpm

10 Year Storm 1,932 gpm 3,588 gpm25 Year Storm 2,556 gpm 4,266 gpm

100 Year Storm 3,588 gpm 5,388 gpm

gpm – gallons per minute

Peak Flow(2,500 sq. ft. Roof)

Grass Field Roof

1 Year Storm 0.08 cfs 0.25 cfs

2 Year Storm 0.12 cfs 0.31 cfs

10 Year Storm 0.25 cfs 0.46 cfs25 Year Storm 0.33 cfs 0.55 cfs

100 Year Storm 0.46 cfs 0.69 cfs

cfs – cubic feet per second

Peak Flow(2,500 sq. ft. Roof)

Grass Field Roof

1 Year Storm 0.60 gps 1.85 gps

2 Year Storm 0.90 gps 2.32 gps

10 Year Storm 1.85 gps 3.43 gps25 Year Storm 2.44 gps 4.08 gps

100 Year Storm 3.43 gps 5.15 gps

gps – gallons per second

Peak Flow(2,500 ft. sq. Roof)

Grass Field Roof

1 Year Storm 36 gpm 111 gpm

2 Year Storm 54 gpm 139 gpm

10 Year Storm 111 gpm 206 gpm25 Year Storm 147 gpm 245 gpm

100 Year Storm 206 gpm 309 gpm

gpm – gallons per minute

Stormwater Effects of Urbanization

Change in Peak Runoff FlowBefore and after Development

0%

50%

100%

150%

200%

250%

1 Year Storm 2 Year Storm 10 YearStorm

25 YearStorm

100 YearStorm

Rain Barrels

Video Jug

How to Build a Rainwater Collection System Video

www.Videojub.com

Collection and Dispersal

Collection Systems

– Rain Barrels

– Downspout Collection

– Cisterns

Dispersal Systems

– Rain Gardens

– Bioswales

– Irrigation

Rain Barrels

Rain Barrels

• Collect a small amount of water– 50 to 300 gallons

• Can be unattractive

• The water must be used

Downspout Collectors

Downspout Collectors

Captures 90% of the rainwater

Cisterns

Above Ground

Cisterns

Below Ground

Video

Installing a 30,000 gallon Cistern In Four Minutes

Putting It Together

Control Systems

Sensors plus Logic Circuits

Cistern Sensors

• High Water – Disperse the water– Alarm

• Irrigation Water– Reserve for landscape

• Household Water– Minimum if household water use

• Low Water l– Pump protection

Irrigation System

• Soil moisture

Drip Irrigation Systems

90% Efficiency Rating

Expanding Stormwater Detention Systems into Stormwater

RetentionSmall increase in size creates a large increase in volume.

Small increase in cost delivers a large volume of water.

Mitigates the ¼” to ½” rainfall events.

Condensation

Condensation

Condensation

Untapped Reservoir

Untapped Reservoir

HVAC Condensation

• ½ gallon per hour per ton of air conditioning.

• 1,000 ton air conditioner produces 8 gallons of water per minute.

• Condensation production occurs when the landscape needs the water.

HVAC Condensation

• ½ gallon per hour per ton of air conditioning.

• One ton of air conditioning for every 700 sq. ft. of floor space.

• One ton of air conditioning for every 5,600 cu. ft. of building volume.

Residential Condensation

• 8 to 15 gallons of water per day.

• 60 to 100 gallons per week.

• 250 to 450 gallons per month.

Commercial Condensation

• 15 gallons of water per minute.

• 360 gallons of water per day.

• 2,520 gallons of water per week.

• 10,000 gallons of water a month.

Green • Water • Infrastructure

Green • Water • Infrastructure

Green • Water • Infrastructure

Green • Water • Infrastructure

Green • Water • Infrastructure

Untapped Reservoir

Untapped Reservoir

Untapped Reservoir

Untapped Reservoir

Untapped Reservoir

Questions?

• Green Water Infrastructure• Strategic Planning

• Marketing• Coaching• Training

Tom BarrettGreen Water Infrastructure, Inc.P.O. Box 124Westfield, Indiana 46074(317) 674-3494

Tom.Barrett@JTBarrett.com