Lombardo Associates, Inc. Representative Project Descriptions

Transcription

1 Lombardo Associates, Inc. Representative Project Descriptions Municipal & Private Wastewater Applications Mayo, MD Town of Woodstock, NY Town of Mashpee, MA Los Osos, San Luis Obispo, CA Little Neck- Ipswich, MA

2 PROJECT DESCRIPTION MAYO PENINSULA, MD Integrated Decentralized Wastewater Management System Project: Client: Mayo Peninsula Wastewater Management System - 900,000 gpd 8,000 people Anne Arundel County Department of Public Works 2662 Riva Road Annapolis, MD Wastewater Engineer: Pio Lombardo, P.E. Lombardo Associates, Inc. Boston, MA & Malibu, CA Pio@LombardoAssociates.com Lombardo Associates, Inc. (LAI) was the Engineer of Record for the Mayo Peninsula Wastewater Collection System which serves 3,000 connections within a 9 square mile area adjacent to Annapolis, MD, with a population of approximately 8,000, where integration of growth management and use of wetlands for wastewater treatment were key attributes. Construction completion occurred in 1992 for the $60 million project. LAI designed & implemented an innovative decentralized wastewater management project using: 1. On-site systems 2. Cluster wastewater system 3. Large communal system using: 40 miles of septic tank effluent collection system (50% gravity & 50% pressure) 900,000 gallons per day (gpd) Treatment Process of: recirculating sand filters, constructed bulrush wetlands for nitrogen removal, constructed peat wetland for phosphorus removal UV disinfection Ultimate disposal through an off-shore, submerged aquatic vegetation wetland ` Figure A: Process Flow Diagram

3 Integrated Phase Implementation: The Mayo Peninsula Wastewater Collection System was completed in stages, with the Collection System and 20% of the construction occurring in year 1. Thereafter, an additional 20% of construction occurred each year until completion. Modular development allowed gradual investment and improved operational efficiency. Table 1: Historical Performance Average Data from 01/93 to 08/05 Table 1 (right) presents the treatment performance. Figures 1-5 (below) illustrate the process demonstrated in the process flow diagram of Figure A. Septic Treatment Reduction Tank Plant % of Influent Effluent Influent BOD % (mg/l) TSS % (mg/l) TN % (mg/l) Figure 1A: Typical House Septic Tank Effluent Collection Figure 1B: Typical Small Pump Station Septic Tank Cover Porous Pavement

4 Figure 1C: Typical Large Pump Station Figure 2: Aerial View of Communal Wastewater Treatment System Peat Wetlands Bulrush Wetlands Recirculating Sand Filter (RSF) Figure 3: Bulrush Wetland

5 Figure 4: Peat Wetland During Operation Figure 5: Aerial View of Constructed Offshore submerged aquatic vegetation wetlands

6 PROJECT DESCRIPTION TOWN OF WOODSTOCK, NY Innovative Integrated Decentralized Wastewater Treatment System Project: Integrated Decentralized Wastewater System Town of Woodstock, NY Client: Town of Woodstock, New York Wastewater Engineer: Pio Lombardo, P.E. Lombardo Associates, Inc. Boston, MA & Malibu, CA Lombardo Associates, Inc. engineered an extensive, integrated master plan for the innovative wastewater treatment facility in the Town of Woodstock, New York. Severe site limitations such as shallow bedrock, high groundwater, slowly permeable soils and steep slopes called for innovative system designs in order to overcome the aesthetic impact of the required solution on individual properties. The project punctuated a creative planning and design effort highlighted by: o active homeowner participation o enactment of strong water conservation practices o development of alternative system designs. The Plan proposed the establishment of: The Hamlet Wastewater Management District with a centralized wastewater system for the 460 connections. Septic tank effluent collection and aquaculture treatment using UV disinfection system with river discharge. Three On-site Wastewater Management Districts.

7 The implemented systems, at a capital cost of approximately $14 million, were: o Low-cost, low energy use sludge management system for small communities o Capacity development for small communities to effectively operate & maintain wastewater treatment facilities. o Innovative water efficiency programs or technique to reduce wastewater infrastructure costs. o Innovative 432 connection septic tank effluent collection system using a 2-mile single-barrel siphon to avoid pump station, discharging to a 0.23 MGD innovative draft tube oxidation ditch with vacuum drying beds, UV disinfection and discharge to the Saw Kill River. o Repair of 200+ residential and commercial on-site wastewater systems using a combination of conventional and innovative systems (predominately sand filters, leachfields and mounds) in individual and cluster formats. The Hamlet Plan was overwhelmingly accepted by referendum (7-1 vote). 2 of the 3 proposed districts became established as the first On-site Wastewater Management Districts in New York State and first large scale septic system rehabilitation program in the US.

8 TOWN OF MASHPEE, POPPONESSET BAY, & WAQUOIT BAY EAST WATERSHEDS Nitrex TM Technology Scenarios Plan Conventional Sewer Systems = $ $600+ million Nitrex TM Approach = $279 million Project: Wastewater Engineer: Town of Mashpee, Popponesset Bay & Waquoit Bay East Watersheds Nitrex TM Technology Scenario Plan Pio Lombardo, P.E. Lombardo Associates, Inc. Boston, MA & Malibu, CA Pio@LombardoAssociates.com Lombardo Associates, Inc. (LAI) was retained by the Mashpee Sewer Commission to prepare a Nitrex TM Technology based wastewater management plan for the Town of Mashpee for the Project Planning Area (PPA) of the East Waquoit and Popponesset Watersheds. The Nitrex TM Technology based plan was to achieve the TMDL requirements as specified by the Massachusetts Department of Environmental Protection, and thereby can be compared on an equal basis with the conventional sewering option. The Nitrex TM Technology Scenario Plan includes: 1. Cluster Systems 2. Individual Onsite Nitrex TM Treatment Systems for application as: a. Retrofit to properties b. New systems 3. Nitrex TM Groundwater Treatment System a. Pump and Treat b. Permeable Reactive Barrier (PRB) 4. Hybrid of the above A summary of the capital and annual O&M costs of the Nitrex TM Technology based Scenarios are presented on Tables 1 and 2.

9 Table 1. Nitrex TM Scenario Costs Compared to Complete WW System Nitrex TM Technology Scenarios Capital Cost Capital Cost / EDU (house) Nitrex TM Technology Capital Cost as % of Complete WW System w/ Sewers Nitrex TM Technology Capital Cost as % of Sewers Connected to Existing WWTP & Expansion 1. Cluster Systems $280,546,000 $40,000 61% 52% 2. Individual Systems $251,970,000 $30,000 (1) 55% 47% 3. Groundwater Treatment $143,636,703 $20,316 31% 27% 4. Stearns & W heler Scenario 4 Proposed Estimates - low end (2,3) $460,000,000 $66, % 85% 5. Stearns & W heler Scenario 1 Proposed Cost Estimates - high end (2,3) $540,000,000 $66, % 100% (1) MA State Tax Credit of $6,000 may be available to property owners with septic system repair. (2) The Stearns & Wheler proposed cost estimates in the March 2008 Draft Alternative Scenarios Analysis Report do not include allowances for land acquisition, acquisition of needed WWTPs, and treatment costs at the Falmouth and Barnstable WWTPs. (3) Ratio of Captial Cost are higher than the per EDU ratio due to the fact that the Stearns & Wheler proposal is to sewer more properties than proposed by LAI. Table 2. Nitrex TM Scenarios Annual O&M Speed of Implementation & Water Quality Improvement. Nitrex TM Technology Scenarios Annual O&M Costs / EDU 1. Cluster Systems $ Individual Systems $ Groundwater Treatment - Pump & Treat $223 The Nitrex TM Technology options can achieve the desired water quality improvements more quickly than treating wastewater because treating wastewater will require the groundwater to cleanse itself after excess nitrogen loadings are reduced. According to the USGS, this will take years after the treatment systems are functioning. Conventional sewering may take years to complete. The Nitrex TM PRB and pump and treat systems can address groundwater just prior to its reaching surface water bodies. 4. Groundwater Treatment - PRB $ Conventional Sewerage System $700 - $1,000 In addition to the speed of implementation, these two Nitrex TM options have the benefit of treating land use nitrogen loads as well as nitrogen loads from upstream sources. The Nitrex TM Scenarios explicitly delineate the specific parcels that need to have their wastewater treated to achieve the water quality goals for the project planning area. The Onsite Scenario is similar to the Cluster System Scenario, in that the same basic parcels are treated, with minimal adjustments made to account for watersheds that require 100% removal of wastewater nitrogen. The pump and treat and PRB scenarios are presented as alternatives that offer benefits such as significant capital and operational cost savings as well as the speed of implementation and water quality improvement. The common factor for all scenarios is the required nitrogen removal. The groundwater pump and treat and PRB options require more groundwater flow and quality data than is currently available, as well as specific solute transport data to accurately locate, therefore these scenarios are strictly conceptual and for comparison purposes only. The Nitrex TM Scenarios minimize the undesired growth stimulation that typically occurs with conventional sewers. The costs for Conventional Sewering with complete wastewater system and conventional sewering with connection to existing WWTP are based upon Cape Cod comparables. A detailed PPA conventional sewer plan and costs is being developed by others.

10 PROJECT DESCRIPTION LOS OSOS, CA SAN LUIS OBISPO COUNTY, CA Cost Competitive Decentralized Wastewater Treatment, Dispersal & Reuse Plan Project: Client: Wastewater Engineer: Los Osos Community Wide Study Decentralized Wastewater Treatment System San Luis Obispo County Department of Public Works San Luis Obispo, CA Pio Lombardo, P.E. Lombardo Associates, Inc. Boston, MA & Malibu, CA LAI was retained to develop decentralized wastewater treatment and dispersal/reuse scenarios for the Los Osos Community in San Luis Obispo County, CA. The following two (2) scenarios were developed: 1. Multiple locations within Los Osos 2. Two locations within Los Osos Scenario 1 Multiple Locations Within Los Osos This scenario involves creating 7 sub-zones for the project area, each having its own treatment and dispersal sites. The potential treatment and dispersal sites consist of undeveloped land either on paper streets or on undeveloped lots. Dispersal and treatment sites are not confined to being located in the same zone or sub-area. Sites not utilized for treatment can be available for potential dispersal. For each zone, reuse/dispersal with Title 22 treated wastewater at the individual properties was considered as an alternate disposal method.

11 Scenario 2 Two Locations One in Mid-Town and one in Northeast Region of Los Osos This option will utilize two treatment locations in combination with multiple disposal and reuse locations. Collection system quantities are similar to those in Scenario 1, with the exception of longer distribution piping and pump station force mains. There will be fewer pump stations that will be larger in size and conveying wastewater over a greater distance compared to Scenario 1. For each zone, reuse/dispersal with Title 22 treated wastewater at the individual properties was considered as an alternate disposal method. The following Table summarizes the Capital Cost, Annual O&M and Present Worth estimates for Scenarios 1 and 2 and compares them to the August 2007 Carollo Engineers Fine Screening Analysis Report estimates, using a total of 5,353 Benefit Units (BU) from the Assessment Engineers Report. Summary of Capital Cost, Annual O&M and Present Worth Estimates Project Cost Per BU (in $ millions) Annual O&M Cost ($ Annual Power Use Present Worth 1 ($ millions) Project Cost ($ millions) Annual Scenario O&M / BU Power Use millions) (kwhr) Level 2 Level 3 Level 2 Level 3 (kw) Level 2 Level 3 Scenario Zones $101 $137 $0.019 $0.026 $1.5 $272 2,003, $137 $179 Scenario Zones $92 $135 $0.017 $0.025 $0.8 $149 1,681, $125 $ AFY STEP $ $0.030 $ Fine Screening Report AFY Gravity $ $0.033 $ Level 2 Mitigation 240 AFY STEP $ $0.031 $ AFY Gravity $ $0.033 $ AFY STEP $ $0.034 $ Fine Screening Report AFY Gravity $ $0.037 $ Level 3 Mitigation 600 AFY STEP $ $0.034 $ AFY Gravity $ $0.037 $ Using 5% interest and 40 year planning period. 2 Project cost savings of $15-25 million may be possible with shared septic tanks and lower 4" gravity pipe cost. The LAI decentralized alternative has capital and annual O&M costs approximately 30% - 40% lower than the other identified options. Level 3 project provides the needed mitigation to arrest saltwater intrusion of the Los Osos water supply aquifer. Level 2 project requires purveyors actions to arrest saltwater intrustion. Average Annual

12 Little Neck Ipswich, MA Project Description LAI was retained by the Feoffees of Grammar School to design a Wastewater System for the Little Neck Development in Ipswich, MA that complies with administrative consent order from Massachusetts Department of Environmental Protection (MADEP) to correct inadequate wastewater management in compliance with State Regulations. Project Application Data Location: Ipswich, MA Site Application: Residential with Community Center Installation Date: July 2006 Design Profile Design Wastewater Flow: 35,000 gpd 167 homes: 143 Seasonal and 24 Year Round Residences System Components. 1. Collection System The sewer system collects wastewater from 167 houses and the community center with a conventional gravity collection system with two pump stations. The wastewater flows to the 120,000-gallon Holding Tanks either by gravity or via force main from the two pump stations. 2. Holding Tanks and Transfer Facilities Wastewater collected by the sewer system is conveyed to holding tanks, where it is pumped out and transported to the Ipswich Wastewater Treatment Plant. 3. Management Information System (MIS) The MIS developed for the Little Neck Wastewater system enables real-time flow and operations monitoring via the world wide web. Long Term Solution Options 1. Connection to the Ipswich sewer system 2. Construction of an on Little Neck WWTP and clean water connection to the Ipswich sewer system discharge pipe. 3. Horizontal directional drilling (HDD) and connection to the Ipswich WWTP.