Hudson Basin Wastewater Inventory Analysis

Brian G Rahm & Sri Vedachalam New York State Water Resources Institute

Cornell University Presented at the NYWEA Annual Conference, New York, NY

February 6, 2012

• $36.2 Billion to repair, replace and update over 20 years “Adequate water infrastructure funding is a critical component of urban revitalization, smart economic growth and property tax relief. It is essential for the protection of public health and environment.” – Wastewater Infrastructure Needs of New York State, NYSDEC

• 24% of declines in 30 year stream water quality due to organic waste and/or municipal & industrial inputs

“Many of these declines (in water quality) are considered to be caused by aging infrastructure, specifically wastewater treatment plants that were built or upgraded in the 1970’s and 1980’s, and are now functioning beyond capacity or at reduced levels of efficiency.” – 30 Year Trends in Water Quality of Rivers & Streams in NY State, NYSDEC

Hudson Basin Wastewater Inventory Analysis – Why Now?

NCDC

Hudson Valley Wastewater Inventory

• Publicly Owned Treatment Works (POTWs)

• Descriptive

• NYSPDES database

• Facility

• EPA ECHO compliance database

• Community

• Census

• Receiving Water

• NYSDEC Waterbody Inventory and

Priority Waterbodies List; TMDL status

• Financial needs identified on NYSDEC Intended Use

Plan: Clean Water State Revolving Fund for Water

Pollution Control

Discharge Sub-basin NY SPDES

Design Flow

(MGD)

Actual Flow

(MGD) Combined

Sewer Year Built

Population Served Receiving Water Name

Effluent Exceed (3

Years)

Hudson-Hoosic NY0020397 0.6 0.44 N 1973 3700 HUDSON RIVER 4

Hudson-Hoosic NY0024821 1.5 0.83 N 1971 3800 HOOSIC RIVER 0

Hudson-Hoosic NY0028240 21.3 12.8 Y 1977 80000 HUDSON RIVER 18

Hudson-Hoosic NY0029050 9.5 5.1 Y 1938 15000 HUDSON RIVER-CHAMPLAIN CA 9

Hudson-Hoosic NY0031941 0.26 0.25 N 1939 2000 FISH CREEK 0

Hudson-Hoosic NY0093637 0.12 0.29 N 1939 1800 HUDSON RIVER 3

Hudson-Hoosic NY0131555 0.05 0.03 N 1986 900 BATTEN KILL RIVER 0

Hudson-Hoosic NY0183695 2.5 2.1 Y 1988 15000 HUDSON RIVER 22

Hudson-Hoosic NY0261360 0.06 0.02 N 491 HOOSIC RIVER 9

Descriptive

Facility Receiving Water

Community

Hudson Valley Wastewater Inventory

Issues a regional inventory can help address

1. Capacity: room for/limitations on growth?

2. Source-water quality: protection vs. remediation strategy?

3. Decentralized alternatives to POTWs: when are they appropriate?

4. Opportunity for municipal cooperation: consolidation of services?

Capacity: Wastewater treatment infrastructure

• Additional wastewater treatment capacity exists primarily in the Lower Hudson, especially in Rockland County (concentrated in four major urbanized areas)

• The Wappinger and Middle Hudson have relatively numerous POTWs, but these are generally smaller facilities

- 50,000 100,000 150,000 200,000

Lower Hudson

Hudson-Wappinger

Middle Hudson

Rondout

Hudson-Hoosic

Sum of Excess Capacity (pp equiv) – Sanitary Sewer Only

Nu

mb

er o

f P

OTW

s

20

37

37

27

6

Lower Hudson

Hudson-Wappinger

Middle Hudson

Rondout

Hudson-Hoosic

Capacity: Wastewater treatment infrastructure

• POTWs with sanitary sewers generally have smaller design flows than combined plants

• % Excess capacity at POTWs with sanitary sewer not significantly different than combined sewer plants

• Are we overloading our combined sewer POTWs?

Issues a regional inventory can help address

1. Capacity: room for/limitations on growth?

– Some, but depends on area

– Wastewater infrastructure only one consideration

Source-water Quality: The relationship between POTWs and stream water quality

POTW #1 POTW #2

Stream Flow

Hudson River

“Headwaters” POTW

“Captive Reach”

• Middle Hudson & Wappinger contain more "captive reach length" than all others combined

• Depending on other (admittedly complex) variables, it may be possible to target “headwater” facilities for upgrades and maintenance so as to protect source water quality

• An effectively operating POTW at Poughkeepsie will not guarantee high water quality in the Hudson.

• An effectively operating POTW at Shandaken might help ensure high water quality in the Upper Esopus

• The Wappinger has the most violations and headwater plants

• By itself this is not informative, but one possible strategy for water quality protection in the region would be to bring facilities located on headwaters into compliance (as long as the violations were relevant to water quality issues of concern in that watershed)

Sanitary Sewer Only Number Sum of Actual Flow (MGD)

Sum of Effluent Exceed (3 Years)

Count of Headwaters

Sum of Captive Reach Length (Miles)

Middle Hudson 37 13 324 15 154

Wappinger 37 18 469 17 96

Rondout 27 15 384 12 82

Lower Hudson 20 47 153 10 26

Hudson-Hoosic 6 2 16 2 26

Grand Total 127 94 1346 56 383

Source-water Quality: The relationship between POTWs and stream water quality

• POTWs are bigger on the Hudson • Flow rate of receiving water is orders of magnitude lower for headwater POTWs • Effluent from headwater POTWs tends to have lower [NO3] • The effect on stream NO3 concentration is potentially much higher in headwater

streams

POTW Actual Flow (MGD)

Estimated Mean Annual Stream Flow

(cfs) Estimated POTW Effluent

[NO3] (mg/l) % [NO3] change during

mean flow

Hudson River

Mean 2.65 24,049 9.8 0.5%

Median 1.78 24,049 9.3 0.4%

"Headwaters"

Mean 0.10 11 2.2 18.5%

Median 0.06 5 1.9 2.7%

Source-water Quality: POTWs in the Wappinger

Receiving Water Name

Actual Flow

(MGD)

Drainage Area

(mi^2)

Mean Annual Stream Flow

(est)(cfs)

plant [NO3] estimated

(mg/l) % NO3 change

during min flow

% NO3 change during mean

flow

OTTER KILL TRIB 0.33 2.6 5 2.246 27.8% 56.4% WOODBURY CREEK TRIB 0.07 2.5 5 8.683 43.2% 58.2%

RHINEBECK KILL 0.14 8.1 16 0.500 -1.5% 0.8%

WAPPINGERS CREEK-E BRANCH 0.19 13.1 26 0.650 -0.8% 1.2%

• Impactful POTWs tend to be on streams with a small drainage area (high ratio of effluent flow to stream discharge)

• In some cases (highlighted in red) the receiving stream soon mixes with a larger stream, but not much larger

• Lack of N data in effluent make estimates tenuous • Certainly some cases where a plant is not performing optimally, and has been sited in

a small drainage area • In some cases, effluent may actually lower [NO3] in-stream

Source-water Quality: Headwater POTWs in the Wappinger

Issues a regional inventory can help address

2. Source-water quality: protection vs. remediation strategy?

– Some headwater plants should be a priority

– A parallel strategy?

Decentralized alternatives to POTWs

• Soil-based septic systems serve 20-25% HH in the U.S. – 1.5m HH or 4m people in NY

• Current paradigm (septic skeptic)

• Soil suitability – 10NYCRR 75 and 75-A

– NYSDOH

• USDA-NRCS provides a 3-point rating for each soil series, based on various physical/chemical properties:

– Not limiting (highly suitable)

– Somewhat limiting

– Very limiting (highly unsuitable)

County Area (sq. mi.)

Not limiting (%)

Somewhat limiting(%)

Very limiting (%)

Albany 531 0.8 23.4 75.8

Rensselaer 665 0 16.3 83.7

Greene 653 0 21.2 78.8

Columbia 643 4.1 22.2 73.7

Ulster 1143 0 12.2 87.8

Dutchess 824.5 0.2 22.5 77.3

Orange 829 0 33.3 66.7

Putnam 246.25 2.7 34.9 62.4

Rockland 178 4.0 42.6 53.4

Westchester 481.25 2.8 34.1 63.1

Average 0.96 23.26 75.78

Decentralized alternatives to POTWs: Soil suitability for septic

Decentralized alternatives to POTWs: Opportunities to replace POTWs with septic?

Decentralized alternatives to POTWs: Areas of Interest (AOI)

Facility City Facility County AOI size (sq. mi.)

Not limiting (%)

Somewhat limiting (%)

Very limiting (%)

1 Albany 5.18 15.8 36.6 47.5

2 Ulster 8.66 0 57.3 42.7

3 Dutchess 7.39 0 36.0 64.0

4 Albany 7.29 0 48.0 52.0

5 Rensselaer 5.5 0 38.7 61.3

6 Orange 5.76 2.6 64.3 33.2

7 Orange 4.74 0 64.3 35.7

8 Ulster 3.49 0 36.6 63.4

9 Greene 2.10 0 20.5 79.5

Average 1.93 47.11 50.96

Distribution of Soils in AOIs and Respective Counties

• More area under ‘Not limiting’ and ‘Somewhat limiting’ soils in the AOIs provide opportunities for decentralized systems

• Site-specific soil analyses may be needed to determine eligibility

0% 20% 40% 60% 80% 100%

1

2

3

4

5

6

7

8

9

Not limiting Somewhat Limiting Very limiting

0% 20% 40% 60% 80% 100%

ALBANY

ULSTER

DUTCHESS

ALBANY

RENSSELAER

ORANGE

ORANGE

ULSTER

GREENE

Not limiting Somewhat Limiting Very limiting

Decentralized alternatives to POTWs: Areas of Interest (AOI)

Issues a regional inventory can help address

3. Decentralized alternatives to POTWs: when are they appropriate?

– Site-specific analyses needed

– Creation of ‘RME’ can be a viable alternative model

Opportunity for Municipal Cooperation: Consolidation

of POTW Services

• POTWs within 1 mile of each other; what are the issues: • Technical • Historic • Governance • Financial

Opportunity for Municipal Cooperation: Consolidation of POTW Services

• Smaller utilities concerns – Affordability and debt service

– Foregoing maintenance increased risk

• Regional consolidation (AWWA-IWA study) – 3 entities save 17% ($41m annually)

– 1 entity saves 26% ($56m annually)

Region Local Governments (per 100K people)

Hudson Valley 9.8

New York State 8.3

U.S. 6

Issues a regional inventory can help address

1. Capacity: room for/limitations on growth? – Some, but depends on area – Wastewater infrastructure only one consideration

2. Source-water quality: protection vs. remediation strategy? – Some headwater plants should be a priority – A parallel strategy?

3. Decentralized alternatives to POTWs: when are they appropriate? – Site-specific analyses needed – Creation of ‘RME’ can be a viable alternative model

4. Opportunity for municipal cooperation: consolidation of services?

Suggestions & Questions