This appendix describes the methods used creating the Impact Index found in Chapter 11. The Impact Index shows the relative pollutant loadings of wastewater treatment plants (WWTPs) and on-site sewage treatment and disposal systems (OSTDS) in individual reservoir basins. For each West-of-Hudson reservoir, Kensico Reservoir, and West Branch Reservoir, a worksheet similar to the one presented below was created. An explanation of each worksheet entry is given below, followed by the eight worksheets completed for each reservoir.
Known Permanent Watershed Population1
Permitted Number of Sewage Treatment Plants2
Permitted Wastewater flow from WWTPs3
Discharger
Daily Flow
Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter.
Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 532
Watershed Management for Potable Water Supply: Assessing the New York City Strategy
Appendix D
Analysis of Wastewater Treatment Plants and On-site Sewage Treatment and Disposal Systems: The Impact Index
This appendix describes the methods used creating the Impact Index found in Chapter 11. The Impact Index shows the relative pollutant loadings of wastewater treatment plants (WWTPs) and on-site sewage treatment and disposal systems (OSTDS) in individual reservoir basins. For each West-of-Hudson reservoir, Kensico Reservoir, and West Branch Reservoir, a worksheet similar to the one presented below was created. An explanation of each worksheet entry is given below, followed by the eight worksheets completed for each reservoir.
Impact Index Worksheet
Known Permanent Watershed Population1
Permitted Number of Sewage Treatment Plants2
Permitted Wastewater flow from WWTPs3
Discharger
Daily Flow
Parameter
Input from WWTPs Now4
Input w/upgrades5
Input 2010 w/growth6
Phosphorus (lbs/day)
Giardia Cysts (106/day)
Fecal Coliforms (106/day)
Viruses (106/day)
Total Suspended Solids (lbs/day)
Cryptosporidium Oocysts (106/day)
OCR for page 532
Watershed Management for Potable Water Supply: Assessing the New York City Strategy
Known Number of OSTDS7
Estimated Wastewater flow from OSTDS8
Estimated Percent of Population served by OSTDS9
Estimated Population served by OSTDS (@2.5 persons/home)10
Parameter
Input from OSTDS Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
11
17
23
Giardia Cysts (106/day)
12
18
24
Fecal Coliforms (106/day)
13
19
25
Viruses (106/day)
14
20
26
Total Suspended Solids (lbs/day)
15
21
27
Cryptosporidium Oocysts (106/day)
16
22
28
Notes
1.
Population from NYC DEP (1993), and based on 1990 Census values.
2.
Permitted number of WWTPs from Table 5-4.
3.
Permitted flow from WWTPs from Table 5-4.
4.
Obtained from NYC DEP (1993 EIS), Table NC-2 "Existing, Expanded and New WWTPs Summary of No Action/Action Impact on Pollutant Loadings by District and Drainage Basin Totals."
5.
Obtained from NYC DEP (1993 EIS), Table NC-2 "Existing, Expanded and New WWTPs Summary of No Action/Action Impact on Pollutant Loadings by District and Drainage Basin Totals."
6.
Calculated by applying the growth rate observed for the period 1990 to 1996 to the period from 1990 to 2010. The observed annual growth rate of 0.25 percent for the West-of-Hudson basin resulted in a total population increase of 5 percent in 2010. The observed annual growth rate of 1.06 percent for the East-of-Hudson basin resulted in a total population increase of 21.2 percent for the Kensico and West Branch basins in 2010.
7.
Septic system numbers from NYC DEP (1993, Table VIII F-3).
8.
Based on 50 gallons of wastewater per day per person (Chanlett, 1979).
9.
Derived by dividing the estimated population served by OSTDS (#10) by the known permanent watershed population (#1). Values slightly exceeding 100 percent appears to reflect the fact that many of the WWTPs serve schools and not residential subdivisions, while values greatly exceeding 100 percent may be attributable to large numbers of seasonal residences.
10.
Calculated by multiplying the known number of OSTDS (#7) by 2.5 residents. This assumes that there is one OSTDS per residence, 2.5 occupants per residence, and that only residences (not commercial facilities) are served by OSTDS. 2.5 occupants per household is the figure for Florida derived from the 1990 Census values for population (12,937,926) divided by the number of households (5,138,360).
11.
This is the average value for total phosphorus (0.0082 lb/day) found in effluent from conventional septic tank and drainfield systems as reported by Ayres (1993). It has been multiplied by the estimated population served by OSTDS (#10).
12.
Assumes 6.4 percent of the population using OSTDS (#10) is positive for Giardia. This is based on the average of two CDC studies of prevalence of parasites in stool specimens which reported Giardia was found in 7.2 percent of samples examined in 1987 and 5.6 percent of samples examined in 1991 (Kappus et al., 1994). The number of positive residents is then multiplied by the maximum number of Giardia cysts excreted per day by an individual (9 × 106 cysts reported by Knight, 1980). This has been multiplied by 0.05 to reflect reported failure rates (defined as surfacing sewage) for conventional systems. This assumes that the remaining 95 percent of the systems are functional and remove all Giardia cysts.
OCR for page 532
Watershed Management for Potable Water Supply: Assessing the New York City Strategy
13.
This is the value for fecal coliform bacteria (2.7 MPN × 106/100mL) found in effluent from conventional septic tank and drainfield systems as reported by Canter and Knox (1986). It has been multiplied by 0.05 of the total daily flow from OSTDS (#8) to reflect reported failure rates (defined as surfacing sewage) for conventional systems. This assumes that the remaining 95 percent of the systems are functional and remove all fecal coliforms.
14.
This is the value for viruses (22 units/L) found in effluent from conventional septic tank and drainfield systems as reported by Anderson et al. (1991). It has been multiplied by 0.05 of the total daily flow from OSTDS (#8) to reflect reported failure rates (defined as surfacing sewage) for conventional systems. A similar process is applied to the remaining 95 percent of functional systems using the value for viruses (0.002 units/L) found 24 inches beneath the drainfield of conventional systems by Anderson et al. (1991).
15.
Based on negligible value for total suspended solids (mg/L) found in effluent from conventional septic tank and drainfield systems (K. Sherman, FL DOH, personal communication, 1998).
16.
Assumes 0.21 percent of the population using OSTDS (#10) is positive for Cryptosporidium. This is based on the average of two CDC studies of prevalence of parasites in stool specimens which reported Cryptosporidium was found in 0.23% of 216,275 stools examined in 1987 and 0.20 percent of 178,786 samples examined in 1991 (Kappus et al., 1994). The number of positive residents is then multiplied by the average number of Cryptosporidium oocysts excreted per day by each infected individual (1 × 107, which is the midpoint of the range found in Goodgame et al., 1993). This has been multiplied by 0.05 to reflect reported failure rates (defined as surfacing sewage) for conventional systems. This assumes that the remaining 95 percent of the systems are functional and remove all Cryptosporidium oocysts.
17.
This is the average value for total phosphorus (0.0014 lb/day) found in effluent from aerobic treatment systems as reported by Ayres (1993). It has been multiplied by the estimated population served by OSTDS (#10).
18.
This assumes that BACT (aerobic treatment unit) removes virtually all Giardia cysts and that the failure rate, with a stringent regulatory structure, would be negligible.
19.
This reflects the fact that BACT (aerobic treatment unit) removes virtually all fecal coliform bacteria and the failure rate, with a stringent regulatory structure, would be negligible.
20.
This is the value for viruses (0.002 units/L) found in effluent 24 inches beneath the drainfield of conventional septic tank and drainfield systems as reported by Anderson et al. (1991). It has been multiplied by the total daily flow from OSTDS (#8) and assumes that all systems would be functional with adequate regulatory oversight.
21.
Based on negligible value for total suspended solids (mg/L) found in effluent from BACT (aerobic treatment unit) (K. Sherman, FL DOH, personal communication, 1998).
22.
This assumes that functional BACT (aerobic treatment unit) removes virtually all Cryptosporidium oocysts and that the failure rate, with a stringent regulatory structure, would be negligible.
23.
This is the value from #17 with the growth factor described in #6 applied.
24.
This is the value from #18 with the growth factor described in #6 applied.
25.
This is the value from #19 with the growth factor described in #6 applied.
26.
This is the value from #20 with the growth factor described in #6 applied.
27.
This is the value from #21 with the growth factor described in #6 applied.
28.
This is the value from #22 with the growth factor described in #6 applied.
OCR for page 532
Watershed Management for Potable Water Supply: Assessing the New York City Strategy
RESERVOIR: Kensico
Known Permanent Watershed Population
4,432
Permitted Number of Wastewater Treatment Plants
0
Permitted Wastewater flow from WWTPs (gallons/day)
0
Known Number of OSTDS
580
Estimated Wastewater flow from OSTDS (gallons/day)
29,000
Estimated Percent of Population served by OSTDS
31
Estimated Population served by OSTDS (@2.5 persons/home)
1,450
Parameter
Input from OSTDS Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
11.9
2.0
2.4
Giardia Cysts (106/day)
42
0
0
Fecal Coliforms (106/day)
146,770
0
0
Viruses (106/day)
0.1
0
0
Total Suspended Solids (lbs/day)
0
0
0
Cryptosporidium Oocysts (106/day)
0.2
0
0
RESERVOIR: West Branch
Known Permanent Watershed Population
3,210
Permitted Number of Wastewater Treatment Plants
1
Permitted Wastewater flow from WWTPs (gallons/day)
20,000
Discharger
Daily Flow
Clear Pool Camp
20,000
Parameter
Input from WWTPs Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
0.8
0.2
0.3
Giardia Cysts (106/day)
13.6
13.6
16.3
Fecal Coliforms (106/day)
302.8
302.8
363.4
Viruses (106/day)
0.4
0.4
0.5
Total Suspended Solids (lbs/day)
3.3
1.7
2.0
Cryptosporidium Oocysts (106/day)
1.2
1.2
1.4
OCR for page 532
Watershed Management for Potable Water Supply: Assessing the New York City Strategy
Known Number of OSTDS
1,777
Estimated Wastewater flow from OSTDS (gallons/day)
222,125
Estimated Percent of Population served by OSTDS
138
Estimated Population served by OSTDS (@2.5 persons/home)
4,443
Parameter
Input from OSTDS Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
36.5
6.1
7.3
Giardia Cysts (106/day)
128
0
0
Fecal Coliforms (106/day)
1,139,501
0
0
Viruses (106/day)
0.9
0
0
Total Suspended Solids (lbs/day)
0
0
0
Cryptosporidium Oocysts (106/day)
0.5
0
0
RESERVOIR: Ashokan
Known Permanent Watershed Population
14,294
Permitted Number of Wastewater Treatment Plants
6
Permitted Wastewater flow from WWTPs (gallons/day)
605,826
Discharger
Daily Flow
Belleayre Mt. Ski Center
29,000
Camp Timberlake
34,000
Onteora Schools
27,000
Mountainside Rest
3,076
Pine Hill WWTP
500,000
Rotron, Inc.
12,750
Parameter
Input from WWTPs Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
2.0
1.3
1.4
Giardia Cysts (106/day)
113.4
113.4
120.2
Fecal Coliforms (106/day)
1070.3
1070.3
1134.5
Viruses (106/day)
3.5
3.5
3.7
Total Suspended Solids (lbs/day)
5.3
5.3
5.6
Cryptosporidium Oocysts (106/day)
11.2
11.2
11.9
Known Number of OSTDS
5,360
Estimated Wastewater flow from OSTDS (gallons/day)
670,000
Estimated Percent of Population served by OSTDS
94
Estimated Population served by OSTDS (@2.5 persons/home)
13,400
OCR for page 532
Watershed Management for Potable Water Supply: Assessing the New York City Strategy
Parameter
Input from OSTDS Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
110.0
18.3
19.4
Giardia Cysts (106/day)
386
0
0
Fecal Coliforms (106/day)
3,437,100
0
0
Viruses (106/day)
2.8
0
0
Total Suspended Solids (lbs/day)
0
0
0
Cryptosporidium Oocysts (106/day)
1.4
0
0
RESERVOIR: Schoharie
Known Permanent Watershed Population
17,662
Permitted Number of Wastewater Treatment Plants
19
Permitted Wastewater flow from WWTPs (gallons/day)
1,751,113
Discharger
Daily Flow
Camp Loyaltown, Inc.
21,000
Colonel Chair Estates
30,000
Crystal Pond Townhouse
36,000
Elka Park
10,000
Forester Motor Lodge
3,900
Frog House Restaurant
1,788
Golden Acre Farms
9,200
Grand George WWTP
500,000
Harriman Lodge
20,000
Hunter Highlands
80,000
Latvian Church Camp
7,000
Liftside at Hunter Mountain
81,000
Mountain View Estates
13,000
Ron-De-Voo Restaurant
1,000
Snowtime
120,000
Tannersville WWTP
800,000
Thompson House Inc.
4,775
Whistle Tree Development
12,450
Parameter
Input from WWTPs Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
12.7
4.5
4.8
Giardia Cysts (106/day)
536.9
299.3
317.3
Fecal Coliforms (106/day)
3,718.4
2,567.8
2,721.9
Viruses (106/day)
16.5
9.3
9.9
Total Suspended Solids (lbs/day)
29.7
10.7
11.3
Cryptosporidium Oocysts (106/day)
53.0
30.8
32.6
OCR for page 532
Watershed Management for Potable Water Supply: Assessing the New York City Strategy
Known Number of OSTDS
7,869
Estimated Wastewater flow from OSTDS (gallons/day)
98,363
Estimated Percent of Population served by OSTDS
111
Estimated Population served by OSTDS (@2.5 persons/home)
19,673
Parameter
Input from OSTDS Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
161.7
26.9
28.5
Giardia Cysts (106/day)
567
0
0
Fecal Coliforms (106/day)
504,602
0
0
Viruses (106/day)
0.4
0
0
Total Suspended Solids (lbs/day)
0
0
0
Cryptosporidium Oocysts (106/day)
2.1
0
0
RESERVOIR: Cannonsville
Known Permanent Watershed Population
17,000
Permitted Number of Wastewater Treatment Plants
7
Permitted Wastewater flow from WWTPs (gallons/day)
2,000,000
Discharger
Daily Flow
Delaware-BOCES
2,500
Delhi
515,000
SEVA Institute
7,800
Allen Center
20,000
Stamford WTP
500,000
Village of Hobart
160,000
Walton WTP
1,170,000
Parameter
Input from WWTPs Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
86.6
4.3
4.6
Giardia Cysts (106/day)
69,658.6
22,847.3
24,217.8
Fecal Coliforms (106/day)
1,471.9
1,324.0
1,403.4
Viruses (106/day)
253.3
82.2
87.1
Total Suspended Solids (lbs/day)
287.3
6.3
6.7
Cryptosporidium Oocysts (106/day)
6,473.3
308.5
327
OCR for page 532
Watershed Management for Potable Water Supply: Assessing the New York City Strategy
Known Number of OSTDS
8,388
Estimated Wastewater flow from OSTDS (gallons/day)
1,048,500
Estimated Percent of Population served by OSTDS
123
Estimated Population served by OSTDS (@2.5 persons/home)
20,970
Parameter
Input from OSTDS Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
172.3
28.70
30.4
Giardia Cysts (106/day)
604
0
0
Fecal Coliforms (106/day)
5,378,805
0
0
Viruses (106/day)
4.4
0
0
Total Suspended Solids (lbs/day)
0
0
0
Cryptosporidium Oocysts (106/day)
2.2
0
0
RESERVOIR: Pepacton
Known Permanent Watershed Population
15,622
Permitted Number of Wastewater Treatment Plants
6
Permitted Wastewater flow from WWTPs (gallons/day)
579,400
Discharger
Daily Flow
Camp NuBar
12,500
Camp Tai Chi
7,500
Margaretville WWTP
400,000
Mountainside Farms, Inc.
49,800
Regis Hotel
9,600
Roxbury Run Village
100,000
Parameter
Input from WWTPs Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
8.6
1.5
1.6
Giardia Cysts (106/day)
227.2
82.1
87
Fecal Coliforms (106/day)
2,396.3
407.2
431.6
Viruses (106/day)
7.0
2.6
2.8
Total Suspended Solids (lbs/day)
21.9
3.3
3.5
Cryptosporidium Oocysts (106/day)
23.5
8.9
9.4
Known Number of OSTDS
6,417
Estimated Wastewater flow from OSTDS (gallons/day)
802,150
Estimated Percent of Population served by OSTDS
103
Estimated Population served by OSTDS (@2.5 persons/home)
16,043
OCR for page 532
Watershed Management for Potable Water Supply: Assessing the New York City Strategy
Parameter
Input from OSTDS Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
131.9
22.0
23.3
Giardia Cysts (106/day)
462
0
0
Fecal Coliforms (106/day)
4,115,029
0
0
Viruses (106/day)
3.4
0
0
Total Suspended Solids (lbs/day)
0
0
0
Cryptosporidium Oocysts (106/day)
1.7
0
0
RESERVOIR: Rondout
Known Permanent Watershed Population
4,170
Permitted Number of Wastewater Treatment Plants
1
Permitted Wastewater flow from WWTPs (gallons/day)
180,000
Discharger
Daily Flow
Grahamsville WWTP
180,000
Parameter
Input from WWTPs Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
0.3
0.3
0.3
Giardia Cysts (106/day)
12.7
12.7
13.5
Fecal Coliforms (106/day)
33.5
33.5
35.5
Viruses (106/day)
0.4
0.4
0.4
Total Suspended Solids (lbs/day)
0.1
0.1
0.1
Cryptosporidium Oocysts (106/day)
1.5
1.5
1.6
Known Number of OSTDS
1,414
Estimated Wastewater flow from OSTDS (gallons/day)
176,750
Estimated Percent of Population served by OSTDS
85
Estimated Population served by OSTDS (@2.5 persons/home)
3,535
Parameter
Input from OSTDS Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
29.1
4.8
5.1
Giardia Cysts (106/day)
102
0
0
Fecal Coliforms (106/day)
906,728
0
0
Viruses (106/day)
0.7
0
0
Total Suspended Solids (lbs/day)
0
0
0
Cryptosporidium Oocysts (106/day)
0.4
0
0
OCR for page 532
Watershed Management for Potable Water Supply: Assessing the New York City Strategy
RESERVOIR: Neversink
Known Permanent Watershed Population
1,557
Permitted Number of Wastewater Treatment Plants
0
Permitted Wastewater flow from WWTPs (gallons/day)
0
Known Number of OSTDS
822
Estimated Wastewater flow from OSTDS (gallons/day)
102,750
Estimated Percent of Population served by OSTDS
132
Estimated Population served by OSTDS (@2.5 persons/home)
2,055
Parameter
Input from WWTPs Now
Input w/ upgrades
Input 2010 w/ growth
Phosphorus (lbs/day)
16.9
2.8
3.0
Giardia Cysts (106/day)
59
0
0
Fecal Coliforms (106/day)
527,108
0
0
Viruses (106/day)
0.4
0
0
Total Suspended Solids (lbs/day)
0
0
0
Cryptosporidium Oocysts (106/day)
0.2
0
0
REFERENCES
Anderson, D. L., A. L. Lewis, and K. M. Sherman. 1991. Human enterovirus monitoring at on-site sewage disposal systems in Florida. Pp. 94-104 In On-Site Wastewater Treatment, Proceedings of the Sixth National Symposium on Individual and Small Community Sewage Systems. St. Joseph, MI: Amer. Soc. Ag. Engineers.
Ayres, A. 1993. Onsite Sewage Disposal Systems Research in Florida: An Evaluation of Current OSDS Practices in Florida . Tallahassee: Florida Department of Health and Rehabilitative Services.
Canter, L. W., and R. C. Knox. 1986. Septic Tank System Effects on Groundwater Quality. Chelsea, MI: Lewis Publishers Inc.
Chanlett, E. T. 1979. Environmental Protection. New York, NY: McGraw-Hill.
Goodgame, R. W., R. M. Genta, A. C. White, and C. L. Chappell. 1993. Intensity of infection in AIDS-associated cryptosporidiosis. Journal of Infectious Diseases 167:704–709.
Kappus, K. D., R. G. Lundgren, Jr., D. D. Juranek, J. M. Roberts, and H. C. Spencer. 1994. Intestinal parasitism in the United States: Update on a continuing problem. Am. J. Trop. Med. Hyg. 506:705–713.
Knight, R. 1980. Epidemiology and transmission of giardiasis. Transactions of the Royal Society of Tropical Medicine and Hygiene 74(4):433–435.
Marx, R., and E. Goldstein. 1993. A guide to New York City's reservoirs and their watersheds. New York, NY: Natural Resource Defense Council.
New York City Department of Environmental Protection (NYC DEP). 1993. Final Generic Environmental Impact Statement for the Proposed Watershed Regulations for the Protection from Contamination, Degradation, and Pollution of the New York City Water Supply and its Sources . November 1993. Corona, NY: NYC DEP.