Littleton, MA Smart Sewering Strategy: Smart Sewering Strategy: - - PowerPoint PPT Presentation

Littleton, MA Littleton, MA – – Smart Sewering Strategy: Smart Sewering Strategy: Affordable Green Sewering, Fit Affordable Green Sewering, Fit-

• For

For-

• Purpose

Purpose Paul Knowles Paul Knowles

Green First: December 8, 2011 Falmouth MA

Introduction

• Intro to Littleton challenge and principles of

smart sewering

• The six steps of smart sewering analysis
• Opportunities for green decentralized

solutions for the cape, provided by a Responsible Management Entity

Motivation for sewer in Littleton

• Affordable at

small-scale

• Concentrate

growth in the commercial center

• Consider social

and ecological benefits

Anticipated Wastewater Flows – 20 year build-out

Use Flow (gpd)

• Yr. 0
• Yr. 5
• Yr. 10
• Yr. 15
• Yr. 20

Park & Co. Retail 10,000

• 7,000

3,000

• Restaurant

28,000

• 19,600

8,400

• Hotel

11,000

• 7,700

3,300

• Medical

Office 4,800

• 3,360

1,440

• VCB

Retail 7,500 1,000

• 3,275
• 3,225

Restaurant 20,000 500

• 10,900
• 8,600

Residential 38,500 11,000

• 10,945
• 16,555

Office 20,000 11,000

• 400
• 8,600

VOD Industrial 14,400

• 7,200

3,312 3,888 Office Commercial 7,500

• 3,750

1,725 2,025 Wells/IBM Office Commercial 47,000 25,000 12,500 4,500

• 5,000

KIMBALL* Commercial 15,000 15,000

• TOTAL

63,500 50,160 57,110 5,037 47,893 CUMULATIVE 63,500 113,660 170,770 175,807 223,700

Smart Sewering Case Study: Littleton, MA

Q) How do we keep a 185,000 gpd system affordable without requiring a larger sewer disctrict? A) Perform a Smart Sewering Study which considers:

• 1. Community values
• 2. Environmental issues
• 3. Minimizing risk to tax base
• 4. Appropriate technology
• 5. Improving affordability for users
• 6. Economic Feasibility Analysis

Community Values

20 Parameters: Environmental, Economic and Social

Community Values

232 responses: top 4 parameters by score

Environmental Issues

3 town wells in Merrimack River Watershed

CONCORD RIVER WATERSHED MERRIMACK RIVER WATERSHED I-495 STUDY AREA

Environmental Issues

• Water

distribution in Littleton

• Recharges are
• n-lot septic

system

• Net transfer of

water from Merrimack to Concord

The Massachusetts Executive Office of Environmental Affairs (EOEA) and the Charles River Watershed Association/ESS Group (2007), Community Water Budget Report, Town of Littleton

CONCORD RIVER WATERSHE D MERRIMACK RIVER WATERSHED

Environmental Issues

APRIL (HIGH FLOW) SEPTEMBER (LOW FLOW) Sub-basin Name Area (Mi²) Natural Stream Flow (MGD) Human Total Vol Impact (MGD) Human Relative Impact (%) Natural Stream Flow (MGD) Human Total Vol Impact (MGD) Human Relative Impact (%) Bennet's 7.1 14.67

• 2.32
• 15.83

2.25

• 1.5
• 66.57

Beaver 13.1 27.49

• 0.9
• 3.28

4.27

• 1.15
• 26.87

Gilson 3.4 6.73

• 0.19
• 2.77

0.11 2.33 Vine 9.9 19.62

• 0.37
• 1.9

2.95 0.09 2.93 Fort Pond 7.2 14.27

• 0.08
• 0.58

1.3 0.05 3.72 Nagog Pond 0.6 1.16 0.18 1.05 0.05 4.87

Resulting change in natural stream flow during high and low seasonal flow – green are Merrimack sub- basins, pink are Concord sub-basins

Environmental Issues

Considered when locating recharge facilities

MERRIMACK WATERSHED Alternative recharge area 1.5 miles away Suitable recharge area within study area 72 acres within Zone III. Mix of I-495 DOT and developer land

Minimizing Financial Risk - Phasing

Reducing carrying costs by using technologies that are affordable at small scale and then installing capacity in phases to match growth

Large carrying costs – higher risk of tax increase to subsidize user rate Small carrying costs – reduced risk to tax base and user

Minimizing Financial Risk - Phasing

Phase 1 2 3 4 5 TOTAL Year 5 10 15 20 Flow (gpd) 30,000 38,000 61,000 23,500 29,500 182,000 Anticipated Connections 100 127 203 78 98 607 Capital Cost ($) 4,182,400 3,610,302 6,718,555 3,000,544 4,366,569 21,878,371 Sewer Length Required (LF) 18,200 6,333 10,167 3,917 4,917 43,550 Area Required (acres) 1.67 2.11 3.39 1.31 1.64 10.12 TOTAL Year Flow (gpd) 182,000 Anticipated Connections 607 Capital Cost ($) 17,024,590 Sewer Length Required (LF) 43,550 Area Required (acres) 9

Smart Phasing Conventional Phasing

Assumptions:

• Includes cost of: onsite appurtenance, collection,

secondary treatment and groundwater dispersal

• Does not include cost of land
• In both scenarios the majority of land is required

for dispersal

• Treatment costs based on the ability to achieve

secondary treatment at $20/gpd installed between scale of 23,500 and 182,000 gpd by using available technologies

Minimizing Risk – Private ownership

Design-Bid-Build Conventional Approach (implementation through public ownership) Design-Build-Operate- Finance (implementation through private ownership) Design Build Design Build Cost Town Private Entity Schedule Completion Town Private Entity Construction Warranty Town Private Entity Asset Management Compliance Guarantee Town Private Entity Capital Replacement Town Private Entity O&M Cost Town Private Entity Residual Disposal Cost Town Private Entity Life Cycle Cost Town Private Entity Finance Long-Term Financing Town Private Entity Interest Rate Risk Town Private Entity

Risk Allocation Table: Private vs. Public Ownership Cost of private debt will result in higher user rates but will remove the risk to the tax base

Minimizing Risk – Private Ownership

Conventional WW Ownership Options in MA:

• Governmental - Municipal/County
• Quasi-Governmental Authority, Special District,

Public Nonprofit

• Private Nonprofit Cooperative or Association

Alternative WW Ownership Options in MA:

• Private For-Profit Utility
• Public Private Partnerships – P3

Minimizing Risk – Private ownership

Private For-Profit Utility:

In MA Private wastewater entities are not regulated by the Department of Public Utilities. MassDEP regulates Privately Owned Wastewater Treatment Facilities (PWTF) under 314 CMR 5.15 based on conditions which are aimed towards Homeowners Associations etc.

Public Private Partnerships (P3):

The town retains ownership and transfers operation and financial

• bligations to a private entity under a long term contract,

generally 20 years or longer. It appears that special state legislation would be required for a municipality to procure a design-build-operate type contract.

Responsible Management of Infrastructure

17

• !!""#!$ %&!'

( )* +(),

• &
• %

.& &

/%

• (0(
• (

() $ Water/Energy/Nutrient Services

RME – Decentralized water reuse in MA

MA Case Study: Gillette Stadium

• MBR technology with design flow of 1.3 MGD. Capital cost in

2005 was $5.2M

• Recycles flush water from 69,000 football fans on game day.
• Sewer enabled economic expansion around the stadium –

multi-user private for-profit utility operation

• 20 year DBO contract with performance risk – reduces

recharge by reuse

Appropriate Technology

Subsurface Flow Treatment Wetlands Packaged Activated Sludge Process systems

Relationship between capacity in gallons per day (gpd) and unit capital cost ($/gpd capacity) for five small- scale wastewater treatment technologies: Activated Sludge Plant (ASP), Sequencing Batch Reactor (SBR), Oxidation Dith (Oxi-Ditch), Membrane Bioreactor (MBR) and Subsurface Flow Treatment Wetland (SSF TW).

Capital costs for small-scale treatment technologies

Appropriate Technology

Relationship between capacity in gallons per day (gpd) and unit operating cost ($/1000 gallons treated) for five small-scale wastewater treatment technologies: Activated Sludge Plant (ASP), Sequencing Batch Reactor (SBR), Oxidation Dith (Oxi-Ditch), Membrane Bioreactor (MBR) and Subsurface Flow Treatment Wetland (SSF TW).

Subsurface Flow Treatment Wetlands Packaged Activated Sludge Process systems

Operating costs for small-scale treatment technologies

Appropriate Technology

“The system is not an unsightly eyesore, does not emit

• dors and emits no loud noise”

Subsurface technologies Open surface technologies

Appropriate Technology

Landscape architecture - Flower and the Butterfly Constructed Wetland at Ko Phi Phi, Thailand

http://mit.biology.au.dk

Appropriate Technology

Courtesy of Worrell Water

Indoor natural systems that achieve reuse

Advanced Treatment with Natural Systems

Living Machine by Worrell Water Technologies Port of Portland building, OR

Appropriate Technology

Cost and carbon metrics for different collection systems

COLLECTION SYSTEM SUMMARY (based on a full build out 182,000 gpd system) Type of Collection Capital Cost ($) Operating Cost ($/yr)

• Pot. Energy

Production ($/yr)

• Pot. Tipping

Revenue ($/yr) Net Operating Cost ($/yr) Net Carbon Footprint (T CO2Eq/yr) STEP $9.1M $87,360 $5,232 $19,700 $62,428 1,540 GRINDER $11.2 M $222,768 $20,614 $0 $202,154 469 GRAVITY $9.4 M $102,757 $20,156 $0 $82,601 379

STEP SEWER PREFERENCE - 56 points. “The cost to build the system has no impact on your current property tax rates or existing utility bills”. Lower net operating costs will reduce risk by improving ability to cover cost of debt GRAVITY SEWER PREFERENCE - 26 points. The system does not produce large amounts of solid, liquid or gaseous waste that requires disposal in landfills or subsequent treatment

• systems. Anaerobic digestion in septic tanks releases methane which has a high global

warming potential.

Centralized vs. decentralized?

Costs of decentralized and centralized can be

• comparable. Available

locations for discharge governs economic feasibility.

Flow (gpd) Users Total Cost ($ 2010) $/gpd inst $/User Fraction of cost in collection Typical user rate ($/gal)* MN Decentralized System 20,770 38 1,476,364 $ 72.83 $ 38,851 23% $ 60 Littleton Proposed 182,000 607 12,245,188 $ 67.28 $ 20,173 28% $ 70 Ph 1 and Ph 2 Proposed 1,800,000 8400 262,000,000 $ 169 $ 36,190 66% $ 63

Cape: Feasible locations for decentralized discharge

1 2*.#34% %%55% %6%7 51 5 *&%"")!

Improving Affordability

Integrate infrastructure to turn waste into resources which can provide a source of revenue to offset sewer costs

WATER POWER FOOD COLLECTION TREATMENT DISPOSAL RESOURCE SUPPLY WASTE PROCESSING FROM OUTSIDE TO OUTSIDE CARBON DOLLARS WATER NUTRIENTS

Improving Affordability

2.0 Dry Ton ANAEROBIC DIGESTER WETLAND TREATMENT STEP COLLECTION SYSTEM REUSE WATER DISCHARGE POWER 607 EDU COMMUNITY FERTILIZER 2.74 Tons food waste 4,100 gpd sludge 182,000 gpd 85,000 gpd 97,000 gpd

• $16/EDU month
• $14/EDU month
• $6/EDU month

2,600 kWh

Integrate infrastructure to turn waste into resources which can provide a source of revenue to offset sewer costs

Improving Affordability – water reuse

Can reduce potable water needs by 40% and save on utility costs

REUSE NETWORK NATURAL TREATMENT SYSTEM

Improving Affordability – Energy Integration

Dry COD (tons/day) Capital Cost ($) O+M cost ($/yr) kWh/yr Revenue Tipping Fees ($/yr) Revenue REC sales ($/yr) Revenue Power sales* ($/yr) Net Operating Profit ($/yr) 0.5 1,801,584 7,500 238,710 36,875 3,581 17,903 50,859 1 2,362,095 15,000 477,419 73,750 7,161 35,806 101,718 2 3,016,601 30,000 954,838 147,500 14,323 71,613 203,435 3 3,832,880 45,000 1,432,257 221,250 21,484 107,419 305,153 5 5,192,057 75,000 2,387,095 368,750 35,806 179,032 508,589

Survey priority number 3: “Reduce waste disposal”: Anaerobic digester to produce electricity from organic waste.

• Multiple revenue sources
• Economic feasibility depends on local availability of waste
• Littleton has Rate 71 to enable purchase from micro-generators

Assumes power is sold to Littleton Electric Light Department at 0.07 $/kWh and REC value is 0.015 $kWh

Source Type of Source Tons per year Chemical Oxygen Demand Smart sewer network Projected Wastewater Solids 112* Littleton Septage Residential Septic Systems 438 Littleton Food Waste Residential Food Waste 218 Nashoba Valley Life Care Center Institutional Health Facility 12 Tre Amici Restaurant 9 Yangtze River Restaurant Restaurant 8 Donelan’s Supermarket Grocery Store 27 TOTAL 711

Data for non-residential sources from Draper/Lennon, Inc., 2002, Identification, Characterization, and Mapping of Food Waste and Food Waste Generators in Massachusetts. Additional sources exist in town not accounted for in this table include schools and Veryfine Sunny Delight Food Processing. Veryfine produces 6,000 tons per year of Chemical Oxygen Demand but this is not readily available. There are 235 food waste generators within a 10 mile radius of the study area that produce 16,000 Tons per year of food waste

Survey performed to identify realistic local availability of organic material (approximately 2 dry tons COD per day).

Improving Affordability – Energy Integration

Economic Feasibility Analysis – Public Ownership

SCENARIO PHASING PRIVATE DEVELOPER CONT. SOURCE OF FINANCING COST OF LAND ($/SF) HOOK UP FEE ($) SUBSIDY FRACTION OF BUILD-OUT ACHIEVED PHASE 1 CAP REQ FROM FINANCING ($) TYPICAL USER RATE ($/MON) RISK OF TAX INCREASE Baseline Smart $2M Municipal 5,000 BG+TF+WR 100% 7,078,381 37 LOW Conv. Conv. $0 Municipal 2 13,000 None 100% 11,578,240 101 HIGH 1 Conv. $2M Municipal 5,000 BG+TF+WR 100% 14,239,768 78 HIGH 2 Smart $0 Municipal 5,000 BG+TF+WR 100% 9,078,381 43 LOW 3 Smart $2M Municipal 2 5,000 BG+TF+WR 100% 7,193,581 38 LOW 4 Smart $2M Municipal 1,000 BG+TF+WR 100% 7,078,381 43 LOW 5 Smart $2M Municipal 10,000 BG+TF+WR 100% 7,078,381 29 LOW 6 Smart $2M Municipal 5,000 None 100% 2,182,400 70 LOW 7 Smart $2M Municipal 5,000 WR 100% 3,869,438 56 LOW 8 Smart $2M Municipal 5,000 BG + TF 100% 5,391,344 51 LOW 9 Smart $2M Municipal 5,000 BG+TF+WR 50% 7,078,381 61 LOW 10 Conv. $2M Municipal 5,000 BG+TF+WR 50% 13,883,221 127 V HIGH

Economic Feasibility Analysis – Private Ownership

SCENARIO PHASING PRIVATE DEVELOPER CONT. SOURCE OF FINANCING COST OF LAND ($/SF) HOOK UP FEE ($) SUBSIDY FRACTION OF BUILD-OUT ACHIEVED PHASE 1 CAP REQ FROM FINANCING ($) TYPICAL USER RATE ($/MON) RISK OF TAX INCREASE Baseline Smart $2M Municipal 5,000 BG+TF+WR 100% 7,078,381 37 LOW Conv. Conv. $0 Municipal 2 13,000 None 100% 11,578,240 101 HIGH 1 Smart. $2M SRF 10,000 BG+TF+WR 100% 7,078,381 90 NONE 2 Smart $2 M Private 10,000 None 100% 7,078,381 148 NONE

• High-capital cost of biogas and water reuse and low hook-up make less

sense under private financing

• Rates are 4 times higher if risk is completely removed from tax-base

and only those that are served by the system have to pay for the system

• SRF provides an affordable way of removing risk from the town

Conclusions for Littleton

• System designed to remove risk to tax-base,

minimize waste, be affordable and non-offensive

• At small scale natural systems and STEP sewer were

most affordable.

• This enabled modular, low-risk expansion
• Subsidy via biogas and water reuse provides a very

affordable service if public financing is secured

• These subsidies are not affordable if private finance

is used to remove all risk to tax-base

• A P3 or SRF funded project will allow the best of

worlds but will require special legislation

Relevance to Cape Cod

Cape Cod Commission presentation in April, 2011

Feasibility of a green and decentralized treatment network for the Cape needs studying.

Relevance to Cape

• Green tech (and other tech) that performs

enhanced nutrient removal is affordable at scale of decentralized-utility

• Proper feasibility study of decentralized sewer costs

versus disposal options should be performed – need to get out of Zone II discharge

• Mechanism for RME to provide long-term
• perations, risk management, ownership and

financing exists in MA. An economic feasibility study would be required

• RME can configure utility to single goal of the
• region. DBO is key for the RME to undertake risk

Relevance to Cape

• Solution for Littleton was tailor-made to needs
• f the town
• Motivations in the Cape are different
• Natural systems are affordable at small-scale

and can be phased according to priorities

• Decentralized sewer costs should be based on

the right sewer technology and specific scenario

• Economic advantage of subsidy, alternative
• wnership and management should be

investigated

Littleton, MA Littleton, MA – – Smart Sewering Strategy: Smart Sewering Strategy: Affordable Green Sewering, Fit Affordable Green Sewering, Fit-

• For

For-

• Purpose

Purpose Thank you for your attention Thank you for your attention

Green First: December 8, 2011 Falmouth MA

Decentralized systems are not new

Salveson et al. report on about 240 small-scale systems. There are many more

Map adapted from information presented in: Salveson A., Zhou, Z., Finney B.A., Burke, M., Chan Ly, J., 2009, Low-Cost Treatment Technologies for Small-Scale Water Reclamation Plants, Water Reuse Foundation

Advanced Treatment with Natural Systems

SAGR with patented FBA technology, by Nelson Environmental Canada Steinbach Manitoba Aerated Lagoon nitrogen polishing

RME - Distributed utility in MN

Morrison Mille Lacs Pine Kanabec Benton Isanti Chisago Anoka Sherburne Washington Meeker Wright Mc Leod Carver Hennepin Ramsey Scott Dakota Sibley

• St. Paul

Minneapolis

RME Distributed utility in MN

Typical range of monthly user fees for 21 systems

RME - Waste to energy in NJ

Ridgewood, NJ – Retrofit existing plant to be carbon neutral

• DBOF P3 with Middlesex water with buyout option. Utility

assumes all performance risk

• Optimizing Renewable Energy via Solar + Internal and

External Carbon Sources. Goal = Net Zero Energy