Large Decentralized Systems a Sustainable Wastewater Solution

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1 Large Decentralized Systems a Sustainable Wastewater Solution Agenda The Good Fight Centralized Exposed in the Real World Decentralized Model System Examples Dennis F. Hallahan, P.E. Technical Director Infiltrator Water Technologies

2 The Good Fight

3 Save the Bay

4 require less polluting sewers

5 Decentralized Obstacles to Overcome How is Decentralized to compete? Know our weaknesses: 1. Lack of knowledge and public misperception 2. Legislative and regulatory constraints 3. Lack of management programs 4. Financial barriers 5. Land Intensive

6 Some Questions for you: A comparison of Centralized and Decentralized wastewater treatment models: 1. Which model pollutes more? 2. Which model costs more? - construction - operations and maintenance 3. Which model is sustainable? 4. Which model transfers water from one watershed to another? 5. Which model depletes groundwater? 6. Which model uses more energy? What are other variables to measure?

7 The Solution, More Big Pipe

Some Questions for you: How many inches of rain cause sewers to overflow? 1. Over 3 2. 1.5 3. 1.0 4.

9 Some Questions for you: How many inches of rain cause sewers to overflow? 1. Over ¼ EPA Consent Decree Resulted in collection tunnels, when completed there will still be an estimated 600 million gallons of CSO s To fund this rates will go from $15/month to $100/month

10 St. Louis

11 What is a CSO?

It is among hundreds locally that release untreated waste after heavy

12 What do CSO s look like? This CSO points directly at Lake Erie at the beach at a State Park. It is among hundreds locally that release untreated waste after heavy rains This CSO in Cleveland discharged so much untreated waste after heavy rains it took on the appearance of a brown water fall.

16 Boston CSO s

19 Note Ohio: when completed they will still have 292 million gallons of overflows.

20 From U.S. News: municipal sewers, with little public recognition, are overflowing or breaking down with disturbing regularity, releasing mega amounts of pollutants. San Diego had a raw sewage spill of 34 million gallons and small-town Fort Pierce, Fla., was hit with 8 million gallons. A downpour prompted the Milwaukee sewer authority to discharge more than a billion gallons of raw sewage into area waterways and Lake Michigan. All told, the EPA projects that combined sewer overflows (or CSOs) discharge 1.2 trillion gallons of sewage and storm water a year enough to keep Niagara Falls roaring for 18 days.

21 Comparison of Failures Let s do the math: EPA Estimated reported overflows: 1.2 TRILLION gallons per year How many onsite systems does this equate to? - Census: 2.7 people per home - 60 gpd/person = 162 gpd/system Trillion gal/yr = 3.9 Billion gal/d BGD/(162 gpd/system) = 20M homes So this equates to over 20 million homes failing continuously every day. Which is better for the environment?

22 Sustainability?... InSanitation

23 More Questions for you: A comparison of Centralized and Decentralized wastewater treatment models: 1. Which system gets more public funding? 2. What is the cost breakdown ratio? a. equal to the percentage of users? (25-30%) b. 10:1 (10% of funding goes to onsite) c. 100:1 (1%) d. 500:1 (0.2%)

24 Decentralized Wastewater Treatment The collection, treatment, and dispersal of wastewater at or near its point of origin An alternative to conventional gravity sewers and WWTP s On-site systems have all components on a single property Decentralized systems have the components on or near the site of generation

25 The EPA Supports Decentralized Systems In 1997, the EPA submitted a Response to Congress on Use of Decentralized Wastewater Treatment Systems EPA s Executive Summary: Adequately managed decentralized wastewater systems are a cost-effective and long-term option for meeting public health and water quality goals...

26 US EPA Published four short papers Introduction to Decentralized Wastewater Treatment: A Sensible Solution Decentralized Wastewater Treatment can be Green and Sustainable Decentralized Wastewater Treatment can Protect the Environment, Public Health, and Water Quality

27 Decentralized System Benefits: Sustainable Land Development Reduced watershed impacts Cost Effective Flexible in Design Lower life-cycle cost Build on land not accessible to public sewer/infrastructure Phased building

28 Community/Cluster Systems Typical System Schematic

29 The lines are getting blurred Primary aspects of a centralized system: 1. Collection: Gravity, pressure, or vacuum sewers system must be watertight! 2. Treatment: Septic Tank, Sand filter, Full Scale WWTP 3. Disposal: many options (products and distribution type) 4. O&M: Public, Quasi-public, private

30 Large Decentralized Systems 1 Omemee, ON 320,000 gpd 2 Los Osos, CA 1.6 MGD 3 Gillette, MA 1.2 MGD 4 Hopkinton, MA 200,000 gpd 5 Plymouth MA 350,000 gpd 6 Kingston, MA 125,000 gpd 7 Port Perry, ON 200,000 gpd 8 Port Burwell, ON 280,000 gpd 9 Washington, IN 21 MGD 10 Gold Beach, OR 2.0 MGD

31 Large System Designs Project with a major civil engineering firm (ENR top 10) - Casino - 300,000 gpd - Clay Soils gpd/sf

32 Final System Design 200,000 Less than 1.0 gpd/sf

33 Los Osos, CA Design Flow: 1.6 MGD Install Date: Summer-Fall 2013 Collection System Type: Gravity sewers and lift stations Treatment Type: Membrane Bioreactor Dispersal System: Chamber field Issues Resolved: Small lots, outdated systems, code compliant systems could not fit, Long history of nitrogen issues. Coastal community, N- sensitive Ocean outfall prohibitive, needed to address saltwater intrusion

34 Los Osos Recharge Area

35 Gold Beach, OR The Problem: Existing centralized system was experiencing I&I problems. This resulted in the plant overflowing, solids carry over and then the recharge system plugging and then overflowing. Community was also sensitive to saltwater intrusion. Other options investigated: Ocean Outfall, replace piping Solution: Selected I&I repair program Replace and expand the disposal fields

36 Gold Beach, OR Design Flow: 2 MGD Install Date: Summer 2013 Collection System: Existing gravity sewers and lift stations Treatment Type: Sequencing Batch Reactor Dispersal System: from 9 beds to 21 3 separate zones of 7 beds each each fed by its own pump, this allows for O&M flexibility

37 Gold Beach Pumps

38 Omemee, Ontario Canada: The Problem: Existing system was over capacity. Ban on new development and growth in the village. Tourism dependent upon water activities. Other options investigated: Gravity sewer with several lift stations with grinder pumps to the adjoining town Proved too expensive, $14M Decentralized Solution: Approx. cost of project: $2+ million dollars.

39 Omemee, Ontario Canada Design Flow: 300,000 gpd Install Date: Spring-Summer 2013 Collection System: Existing gravity sewers and lift stations Treatment Type: Lagoons Dispersal System: Chamber field (and spray fields)

40 Omemee Layout:

42 Omemee Site

43 Omemee Disposal Pressure distribution Isolated beds in zones

44 Hopkinton MA The Problem: Town was exceeding the discharge limits. Neighboring town wanted to charge extra fees. Other options investigated: Surface discharge Increased Plant Capacity Decentralized Solution: Intercept the excess flow, divert to a new smaller WWTP and with a dispersal field. Design Flow 200,000 gpd, Installed 2011

45 Hopkinton MA Recharge system to be located open space

46 Large Commercial Systems Concerns? Large Low Pressure Dosed Trench System

47 Storage a design consideration for large peak flow event facilities Gillette Stadium Foxboro, MA: 1 MGD

48 Storage Tank and Treatment Facility

49 Why fight the fight? $2.7M for 40 homes does that raise a red flag? Equates to $67,500 per home With today s onsite s technologies available can we do better? Become involved locally

50 In Conclusion: There is no longer one solution in wastewater treatment, Decentralized Systems can be effective solution Get involved locally You can make a difference Encourage rule development that will enable decentralized systems to compete

51 Thank You Questions? Dennis F. Hallahan, P.E., Technical Director

Milwaukee Metropolitan Sewerage District Conveyance and Treatment System. MACRO made available by

Milwaukee Metropolitan Sewerage District Conveyance and Treatment System MACRO made available by Eric Loucks,, CDM MMSD Collection System Operations MMSD operates an extensive system of sanitary sewers