Table S1 Demographic and Water Use Data for the City of Atlanta

Electronic Supplementary Material

Table S1 Demographic and water use data for the City of Atlanta

# of residents or employees (ARC 2010) / Single-family / 276,000
Multi-family / 144,000
Employee / 378,000
Water use, m3/(capita·yr) (AECOM 2009) / Single-family / 109
Multi-family / 101
Employee / 106
Outdoor water use, m3/(capita·yr) (AECOM 2009) / Single-family / 38.7
Multi-family / 13.8
Employee / 23.5

Table S2 Plant capacity and average daily flow for drinking water treatment

Water Treatment Plant (WTP) / Plant Capacity(AECOM 2009) / Average Daily Flow (the Department of Watershed provided from the City of Atlanta) / Unit
Hemphill / 517 / 152 / 103 m3/day
Chattahoochee / 246 / 144
Atlanta-Fulton County / 341 50% / 83
Total / 931 / 379

Fig. S1 Chattahoochee water treatment plant (WTP)process, which was used for our WTP analysis (Lin 2003)

Table S3Plant capacity and average daily flow for wastewater treatment

Wastewater Reclamation Center / Plant Capacity(AECOM 2009) / Average Daily Flow (provided from the City of Atlanta) / Unit
R.M. Clayton / 462 / 284 / 103 m3/day
Utoy Creek / 167 / 91
South River / 204 / 95
Total / 833 / 469

Fig. S2. Utoy Creek wastewater reclamation treatment (WRT) process, which was used for our WCT analysis (BNR: biological nutrient removal)(Mines et al. 2004; Mines et al. 2006)

Table S4 Infrastructure scale and LCI datasets

Infrastructure / Capacity / Data source / Datasetname
(CH: Switzerland,
RER: Europe) / Per FU, 1m3 water distributed to point-of-use / Calculation
Water supply system / Reference flow: 1.15 m3
Pump station / 1.67E+06 / m3/day / (AECOM 2009; DP&CD 2010; Lin 2003; The City of Atlanta 2005; The City of Atlanta 2008; The City of Atlanta 2009) / pump station/p/CH/I; 1p = 644,546 m3/yr / 1.12E-07 / p* / The capacities (column 2) were divided by the daily average flow rate of 379 103 m3/day(Table S1) andthe life expectancy of 70 years.
Water treatment plant / 931 / m3/day / water works/p/CH/I; 1p = 644,546 m3/yr / 6.27E-08 / p
Booster pump station / 5.60E+05 / m3/day / pump station/p/CH/I; 1p = 644,546 m3/yr / 3.77E-08 / p
Storage tank / 1.57E+05 / m3 / water storage/p/CH/I; 1p = 2,500 m3 / 7.48E-09 / p
Distribution pipeline / 4,340 / km / water supply network/km/CH/I / 5.16E-07 / km
Wastewater collection and treatment system / Reference flow: 0.77 m3
Wastewater collection pipeline / 3,420 / km / (AECOM 2009; DP&CD 2010; Mines et al. 2004; Mines et al. 2006; The City of Atlanta 2005; The City of Atlanta 2008; The City of Atlanta 2009) / sewer grid, class 1/km/CH/I / 2.19E-07 / km / The capacity (column 2) was divided by the daily average flow rate of 469103 m3/day(Table S1) andthe lifespan of 70 years.
Pump station / 2.29E+05 / m3/day / pump station/p/CH/I; 1p = 644,546 m3/yr / 1.94E-08 / p / The capacities (column 2) were divided by the daily average flow rate of 469103 m3/day(Table S1) andthe lifespan of 30 years.
Wastewater treatment plant / 8.33E+05 / m3/day / wastewater treatment plant, class 1/p/CH/I; 1p = 47,100,000 m3/yr / 9.70E-10 / p
Stormwater collection system / Reference flow: 1.25 m3
Stormwater collection pipeline / 3,420 / km / (The City of Atlanta 2005; The City of Atlanta 2008; The City of Atlanta 2009) / sewer grid, class 1/km/CH/I / 3.56E-07 / km / The distance (column 2) was divided by the annual stormwater runoff volume (2.24E+08 m3/yr) and the lifespan of 70 years.
The runoff volume was determined for the sewer system area of 583 km2.

*p: one unit of infrastructure that has a capacity defined in the column 5 (dataset name)

Table S5 Materials, processes and direct emissions for system operation and LCI datasets

Input / Amount / Data source / Dataset name
(CH: Switzerland,
RER: Europe) / Per FU, 1m3 water distributed to point-of-use / Calculation
Water supply system / Reference flow: 1.15 m3
Aluminum sulfate / 2,077,418 / kg/yr / Data provided from the Department of Watershed Management (CoA) for Chattahoochee water treatment plant (144E+03 m3/day) / Aluminum sulfate, powder, at plant/RER U / 4.55E-02 / kg / The consumptions (column 2) were divided by the daily average flow rate of 144 103m3/day for Chattahoochee WTP (Table S2).
Sodium hypochlorite / 1,316,735 / kg/yr / Sodium hypochlorite, 15% in H2O, at plant/RER U / 2.88E-02 / kg
Lime / 1,017,804 / kg/yr / Lime, hydraulic, at plant/CH U / 2.23E-02 / kg
Phosphoric acid / 110,977 / kg/yr / Phosphoric acid, industrial grade, 85% in H2O, at plant/RER U / 2.43E-03 / kg
Hydrofluosilic acid / 231,821 / kg/yr / Fluosilicic acid, 2% in H2O, at plant/US U / 5.07E-03 / kg
Sludge sent to R.M. clayton WRC / 586 / kg/yr / Disposal, digester sludge, to municipal incineration/CH U / 1.28E-05 / kg
Water for filtration bed backwashing / 466 / m3/each / Lin (2003) / Tab water, at user/CH U / 6.43E+00 / kg / The water use (column 2) was divided by the treatment capacity of each filtration bed (20.8E+03 m3/day) and backwashing frequency (every 96 hrs)
Natural gas / 4,414,266 / MJ/yr / Georgia Power / Natural gas, at long-distance pipeline/RER U / 9.66E-04 / m3 / The energy consumption (column 2) was divided by the daily average flow rate of 379 103 m3/day (Table S2).
Electricity / 74,048,700 / kWh/yr / * / 6.15E-01 / kWh

Table S5 Materials, processes and direct emissions for system operation and LCI datasets (continued)

Input / Amount / Data source / Dataset name
(CH: Switzerland,
RER: Europe) / Per FU, 1m3 of water distributed to point-of-use / Calculation
Wastewater collection and treatment system / Reference flow: 0.77 m3
Ferric Chloride (40%) / 524,933 / kg/yr / Data provided from the Department of Watershed Management (CoA) forUtoy Creek wastewater reclamation center / Iron (III) chloride, 40% in H2O, at plant/CH U / 1.22E-02 / kg / The consumptions (column 2) were divided by the daily average flow rate of 91E+03m3/day(the Utoy Creek wastewater reclamation center).
Specific gravity of magnesium hydroxide powder = 2.36
Caustic soda (50%) / 809,648 / kg/yr / Sodium hydroxide, 50% in H2O, production mix, at plant/RER U / 1.88E-02 / kg
Magnesium hydroxide powder / 63,565 / l/yr / Sodium hydroxide, 50% (wt.) in H2O, production mix, at plant/RER U / 5.13E-03 / kg
Dewatering polymer / 29,723 / kg/yr / Aluminum sulfate / 6.89E-04 / kg
Sludge disposal / 2,519,697 / kg/yr / Disposal, municipal solid waste, 22.9% water, to municipal incineration/CH U / 5.84E-02 / kg
Ash to brick / 964,608 / kg/yr / clay and soil, extracted for use / 2.24E-02 / kg
Ash to landfill / 318,596 / kg/yr / Disposal, inert waste, 5% water, to inert material landfill/CH U / 7.39E-03 / kg
Electricity / 136,177,852 / kwh / Georgia Power / * / 6.13E-01 / kWh / The energy consumption (column 2) was divided by daily average flow rate of 469 103m3/day(Table S2)
Natural gas / 91,938,667 / MJ/yr / Natural gas, at long-distance pipeline/RER U / 1.09E-02 / m3
CO2 emission from biogas combustion / 42.5 / g as carbon / Hardy (2011) / Biogenic CO2 emission to air / 1.2E-01 / kg as CO2 / Carbon amount in 0.07785 Nm3/m3 wastewater (RM clayton WRC) = 3.47 mole/m3
Water pollutant discharge / 0.158 / TP, mg/L as P / Mines et al. (2004)Mines et al. (2006) / Total phosphorus emission to water / 1.22E-04 / kg as P
1.83 / TN, mg/L as N / Total nitrogen emission to water / 1.41E-03 / kg as N

*Electricity, hard Coal, at power plant/US U 67%; Electricity, natural gas, at power plant/US U 10%; Electricity, nuclear, at power plant/US U 21%; Electricity, hydropower, at power plant/FR U 2%

Table S6. Material transport and LCI datasets

System / Material / Supplier location or destination / Truck, km / Train, km / Data source / Dataset name / Per FU, 1m3 of water distributed to point-of-use
Truck, tkm / Train, tkm
Water supply system / Aluminum sulfate / Macon, GA / 161 / - / Chemical suppliers’ names were provided from CoA / Transport, combination truck, average fuel mix/US / 7.29E-03 / -
Sodium hypochlorite / Allied Ranger, GA / 129 / 3.70E-03
lime / Campobello, SC / 322 / 7.15E-03
phosphoric acid / Augusta, GA / 274 / 6.62E-04
Hydrofluosilic acid / Red Hill, NC / 418 / 2.12E-03
Sludge sent to RM Clayton WRC / R.M clayton WRC / 16 / - / The sludge amount was provided form the CoA. / 2.06E-07
Total / 2.09E-02 / -
Wastewater collection and treatment system / Ferric Chloride, 40% / Detroit, MI / 32 / 1,175 / Chemical suppliers’ names were provided from the CoA / Transport, combination truck, average fuel mix/USorTransport, train, diesel powered/US / 3.98E-04 / 1.46E-02
Caustic soda, 50% / Savannah, GA / 418 / - / 8.01E-03 / -
Magnesium hydroxide / Philadelphia, PA / 24 / 1,448 / 2.36E-04 / 1.41E-02
Dewatering polymer / Waxhaw, NC / 451 / - / 3.16E-04 / -
Ash to brick / Smyrna, GA / 16 / - / The ash amounts were provided form the CoA. / 3.66E-04 / -
Ash to landfill / Buford, GA / 88 / - / 6.65E-04 / -
Total / 9.99E-03 / 2.86E-02

Table S7. Pollutant concentrations of stormwater runoff (Horowitz 2009; Horowitz et al. 2008; USGS 2012)

Water pollutant / Concentration / Unit / Calculation
Phosphorus, water, unfiltered / 3.71E-01 / mg/l as P / Median values of water quality data monitored for rain events (monitoring station number: 02336360, 02336300, 02203655, 02203700, 02336526, and 02336728)
Nitrate, water, filtered / 6.78E-01 / mg/l as N
Nitrite, water, filtered / 1.69E-02 / mg/l as N
Ammonia plus organic nitrogen, water unfiltered / 1.53E+00 / mg/l as N
Potassium, water, filtered / 3.56E+00 / mg/l as K
Sodium, water, filtered / 6.48E+00 / mg/l
Chloride, water, filtered / 8.19E+00 / mg/l
Silica, water, filtered / 4.19E+00 / mg/l as Si
Sulfate, water, filtered / 1.20E+01 / mg/l
Calcium, water, filtered / 1.05E+01
Magnesium, water, filtered / 2.32E+00
Aluminum, water, filtered / 1.37E-01
Cadmium, water, filtered / 3.26E-05
Chromium, water, filtered / 3.74E-04
Copper, water, filtered / 3.96E-03
Iron, water, filtered / 3.08E-01
Lead, water, filtered / 7.37E-04
Manganese, water, filtered / 5.06E-02
Nickel, water, filtered / 1.42E-03
Silver, water, filtered / 1.21E-05
Zinc, water, filtered / 1.20E-02
Barium, unfiltered / 1.18E-01
Beryllium, unfiltered / 5.89E-04
Cobalt, unfiltered / 5.49E-03
Lithium, unfiltered / 2.28E-06
Mercury, unfiltered / 2.44E-05
Molybdenum, unfiltered / 6.10E-04
Strontium, unfiltered / 1.67E-02
Thallium, unfiltered / 2.03E-02
Vanadium, unfiltered / 2.44E-02
Antimony, unfiltered / 4.06E-03
Arsenic, unfiltered / 1.66E-03
Selenium, unfiltered / 1.83E-04

Table S8 Data uncertainty of infrastructure

System / Infrastructure / Basic uncertainty / Data quality indicators / Data uncertainty
Water supply / Pump station for water intake / 3.00 / 1, 1, 1, 1, 4, na / 3.23
Water treatment plant / 3.00 / 1, 1, 1, 1, 4, na / 3.23
Booster pump station / 3.00 / 1, 1, 1, 1, 4, na / 3.23
Storage tank / 3.00 / 1, 1, 1, 1, 4, na / 3.23
Distribution pipelines / 3.00 / 1, 1, 1, 1, 4, na / 3.23
Wastewater collection and treatment / Pump station / 3.00 / 1, 1, 1, 1, 4, na / 3.23
Sewer pipelines / 3.00 / 1, 1, 1, 1, 4, na / 3.23
Wastewater reclamation centers / 3.00 / 1, 1, 1, 1, 4, na / 3.23
Stormwater collection / Sewer pipelines / 3.00 / 1, 1, 1, 1, 4, na / 3.23

Table S9 Data uncertainty of materials, processes,direct emissions, and transportation for system operation

System / Input / Basic uncertainty, GSD2* / Data quality indicators / Data uncertainty, GSD2
Water supply / Water intake / - / Not applicable to input or output for nature
Aluminum sulfate / 1.05 / 2, 3, 1, 1, 1, na / 1.09
Sodium hypochlorite / 1.05 / 2, 3, 1, 1, 1, na / 1.09
Water for filtration bed backwashing / 1.05 / 3, 3, 1, 1, 4, na / 1.53
Lime / 1.05 / 2, 3, 1, 1, 1, na / 1.09
phosphoric acid / 1.05 / 2, 3, 1, 1, 1, na / 1.09
Hydrofluosilic acid / 1.05 / 2, 3, 1, 1, 1, na / 1.09
Sodium hypochlorite / 1.05 / 2, 3, 1, 1, 1, na / 1.09
Natural gas / 1.05 / 1, 1, 1, 1, 1, na / 1.05
Electricity / 1.05 / 1, 1, 1, 1, 1, na / 1.05
Sludge sent to clayton WRC / 1.05 / 1, 3, 1, 1, 4, na / 1.51
Truck transport / 2.00 / 3, 3, 1, 1, 1, na / 2.02
Wastewater collection and treatment / Wastewater effluent discharge / - / Not applicable to input or output for nature
Ferric Chloride (40%) / 1.05 / 2, 3, 1, 1, 1, na / 1.09
Caustic soda (50%) / 1.05 / 2, 3, 1, 1, 1, na / 1.09
Magnesium hydroxide / 1.05 / 2, 3, 1, 1, 4, na / 1.51
Dewatering polymer / 1.05 / 2, 3, 1, 1, 4, na / 1.51
Electricity / 1.05 / 1, 1, 1, 1, 1, na / 1.05
Natural gas / 1.05 / 1, 1, 1, 1, 1, na / 1.05
CO2 emission from combustion of sludge digestion gas / 1.05 / 3, 3, 1, 1, 1, na / 1.12
Water pollutants (TP and TN) / 1.50 / 1, 1, 1, 2, 1, na / 1.50
Sludge disposal / 1.05 / 2, 3, 1, 1, 4, na / 1.51
Ash to brick / - / Not applicable to input or output for nature
Ash to landfill / 1.05 / 2, 3, 1, 1, 1, na / 1.09
Truck transport / 2.00 / 3, 3, 1, 1, 1, na / 2.02
Train transport / 2.00 / 3, 3, 1, 1, 1, na / 2.02
Stormwater collection / Stormwater discharge / - / Not applicable to input or output for nature
Water pollutants / 1.50 / 2, 1, 1, 1, 1, na / 1.50

*GSD2: the square of geometric standard deviation

Table S10 Uncertainty test result

Impact category / Mean / SD / CV / 2.5% / 97.5%
Ozone depletion / 7.17E-07 / 1.46E-07 / 20.4% / 4.92E-07 / 1.07E-06
Global warming / 8.12E-05 / 1.30E-05 / 16% / 6.10E-05 / 1.12E-04
Smog / 7.83E-05 / 1.60E-05 / 20.5% / 5.67E-05 / 1.11E-04
Acidification / 1.16E-04 / 1.93E-05 / 16.7% / 8.69E-05 / 1.60E-04
Eutrophication / 4.66E-04 / 3.75E-04 / 80.5% / 2.69E-04 / 1.27E-03
Carcinogenics / 5.72E-03 / 4.81E-03 / 84.1% / 2.36E-03 / 1.36E-02
Non carcinogenics / 5.92E-04 / 1.37E-03 / 232% / 3.27E-04 / 1.21E-03
Respiratory effects / 4.16E-05 / 8.11E-06 / 19.5% / 2.99E-05 / 6.16E-05
Ecotoxicity / 7.82E-04 / 3.08E-04 / 39.4% / 5.96E-04 / 1.19E-03
Fossil fuel depletion / 1.63E-06 / 2.43E-06 / 149% / 5.01E-07 / 5.77E-06

Table S11 Impact changes for ±10% of infrastructure construction, electricity consumption, and water pollutants in stormwater runoff

Impact category / Infrastructure construction / Electricity consumption / Water pollutants in stormwater runoff
Ozone depletion / 3.0% / 3.8% / 0.0%
Global warming / 3.4% / 5.4% / 0.0%
Smog / 2.4% / 4.9% / 0.0%
Acidification / 1.9% / 6.5% / 0.0%
Eutrophication / 0.5% / 3.9% / 4.2%
Carcinogenic effects / 6.8% / 2.0% / 0.0%
Non-carcinogenic effects / 3.5% / 2.1% / 2.0%
Respiratory effects / 3.9% / 3.9% / 0.0%
Ecotoxicity / 2.6% / 1.0% / 5.5%

References

AECOM (2009) Wastewater management plan. Metropolitan North Georgia Water Planning District. Accessed 25 October 2011

AECOM (2009) Water supply and water conservation management plan. Metropolitan North Georgia Water Planning District. Accessed 9 September 2011

ARC (2010) Cities and Towns - 2010 Yearbook of growth and change. Atlanta Regional Commission. Accessed 1 August 2011

DP&CD (2010) 2011 Comprehensive development plan community assessment executive summary. City of Atlanta. Accessed 28 May 2011

Hardy SA (2011) Achieving economic and environmental sustainability objectives through on-site energy production from digester gas. In: AWEA's 2011 Annual Conference, Orange Beach, Alabama

Horowitz AJ (2009) Monitoring suspended sediments and associated chemical constituents in urban environments: lessons from the city of Atlanta, Georgia, USA Water Quality Monitoring Program. J Soils Sediments 9:342-363

Horowitz AJ, Elrick KA, Smith JJ (2008) Monitoring urban impacts on suspended sediment, trace element, and nutrient fluxes within the City of Atlanta, Georgia, USA: program design, methodological considerations, and initial results. Hydrol Process 22:1473-1496

Lin JC (2003) Determining the removal effectiveness of flame retardants from drinking water treatment processes. Dissertation, Massachusetts Institute of Technology

Mines R, Behrend G, Bell IV H (2004) Assessment of AWT systems in the metro Atlanta area. J Env Manag 70:309-314

Mines R, Lackey L, Behrend G (2006) Performance assessment of major wastewater treatment plants (WWTPs) in the state of Georgia. J Environ Sci Health, Pt A: Environ Sci Eng Toxic Hazard Subst Control 41:2175-2198

The City of Atlanta (2005) 2025 Comprehensive plan. Fulton County Environment and Community Development Department. Accessed 22 February 2011

The City of Atlanta (2008) Atlanta Strategic Action Plan. The City of Atlanta. Accessed 16 November 2011

The City of Atlanta (2009) Official statement relating to City of Atlanta, Georgia - Water and Wastewater Revenue Bonds. The City of Atlanta. Accessed 15 January 2012

USGS (2012) U.S. Geology Survey, Water-resources data for the United States of the year 2010. Accessed 10 February 2012