240 likes | 487 Views
District of Columbia Water and Sewer Authority George S. Hawkins, General Manager. Briefing On: Anacostia River Tunnel Briefing For: ANC 6B. October 26, 2011. Agenda. Welcome and Introductions DC Water Organization and DC Clean Rivers Project (DCCR) Overview
E N D
District of Columbia Water and Sewer Authority George S. Hawkins, General Manager Briefing On: Anacostia River Tunnel Briefing For: ANC 6B October 26, 2011
Agenda • Welcome and Introductions • DC Water Organization and DC Clean Rivers Project (DCCR) Overview • Importance of the Anacostia River • Anacostia River Tunnel (ART) Project Overview • Next Steps
Who We AreThe District of Columbia Water and Sewer Authority (DC Water) • Provides • Drinking water distribution for DC • Required wastewater collection and treatment • Stormwater collection and conveyance • Treats wastewater for a population of 2.1 million • District of Columbia • Montgomery & Prince George’s counties, MD • Fairfax & Loudoun counties, VA • Operates the world’s largest advanced wastewater treatment plant • Average daily capacity, 370 mgd • Peak daily capacity, 1 billion+ gallons • Serves a regional area of approx. 725 Sq Mi Blue Plains Advanced Wastewater Treatment Plant
What is a CSO? 100% of Suburbs 67% of DC 0% of suburbs 33% of DC
DC Clean Rivers Project OverviewWhat is our Purpose? • Control combined sewer overflows to the • Potomac River • Anacostia River • Rock Creek • Relieve flooding in the Northeast Boundary Area • Implemented under a Federal Consent Decree among • US Environmental Protection Agency (US EPA)/ US Department of Justice (US DOJ) • District of Columbia and • DC Water
DC Clean Rivers Project Schedule Consent Decree Requirements * Construction began in February 2010 with the Division W – Blue Plains Site Preparation Contract
DC Combined Sewer System • 1/3 of DC area is served by combined sewers (12,478 acres) • 53 CSO outfalls • 15 to Anacostia • 10 to Potomac • 28 to Rock Creek • Three receiving waters • Anacostia River • Potomac River • Rock Creek
Importance of the Anacostia River • Anacostia – Native American Word (Anaquash) meaning village trading center • Wetland loss, deforestation, and urbanization have significantly degraded the water quality of the Anacostia River • Tidal waters flow 8.4 miles • Joins Potomac at Hain’s Point for 108 miles • Empties into the Chesapeake Bay
Environmental Benefits of the DC Clean Rivers Project • CSO Reduction • 96% Reduction in CSO Volume: • Anacostia: 2,142 to 54 mil gal/yr • Potomac: 1,063 to 79 mil gal/yr • Rock Creek: 49 to 5 mil gal/yr • Number of Overflows Reduced: • Anacostia: 75 to 2/yr • Potomac: 74 to 4/yr • Rock Creek: 30 to 4/yr • Water Quality Improvement • Reduced nitrogen • Bacteria levels will be lower, dissolved oxygen will be higher • Trash/Floatables Reduction • Trash/floatables from CSOs will be practically eliminated • Flooding Relief in Northeast Boundary Area 98% Reduction in CSOs to Anacostia River
DC Clean Rivers Project Funding • Federal Funding • $153.6 million since September 30, 2011 • Working to get more funding • Revenue from ratepayers • Impervious Surface Charge • Fiscal Year 2012 anticipated $302 million • Wholesale Customers • Customers in Maryland & Virginia pay approx. 7.1 percent on most of the project
Anacostia River ProjectsProject Snapshot • 4 large storage/conveyance tunnels • Dewatering pumping station at Blue Plains • Pumping station replacement at Poplar Point • Schedule • LTCP = 20 years (2005-2025) • Nitrogen = 2007-2015 • Cost • LTCP = $2.6 billion • Nitrogen = $950 M • Total > $3.5 billion
Anacostia River TunnelOverview • 23-foot diameter TBM tunnel • Soft ground • 100 ± feet deep and 12,500 feet long • Mining from CSO-019 south to PP-JS • 6 shafts (12 to 75-foot I.D.) • 3 Adits (4.5 to 10-foot I.D.) • 2 Diversion Structures • 6 Odor Control and Venting Facilities • Monitoring & Data Collection System • System Start-up • Design-build contract value: $200 – $250 million CSO-019 CSO-018 M Street CSO-007 CSO-005 PP-JS
CSO-019Site Plan • NPS property • CSA: 3.75 Acres • Two 75-foot ID shafts; ±105 feet deep to top of invert • 100-foot long Inter-Shaft Connector Tunnel • Odor Control and Venting Facility: Eastside Pumping Station • Internal Hydraulic Structures in South Shaft • Contractor interfaces • CSO-019 Diversion and Overflow Facility
CSO-018Site Plan • DDOT property • CSA: 1.25 Acres • 32-foot ID shaft; ±95 feet deep to top of invert • 300-foot long, 10-foot ID adit • Diversion Structure • Odor Control and Venting Facility • Internal Hydraulic Structures within Shaft • Crossings: CSX Tracks and DDOT Retained Ramp
M StreetSite Plan • DMPED property • CSA: 1 Acre • 62.5-foot ID shaft; ±110 feet deep to top of invert • Odor Control and Venting Facility • Internal Hydraulic Structures within Shaft • Contractor interfaces • M Street Diversions • DMPED Development
CSO-007Site Plan • DDOT property • CSA: 2 Acres • 12-foot ID shaft; ±100 feet deep to top of invert • 30-foot long, 4.5-foot ID adit • Diversion Structure • Odor Control and Venting Facility • Internal Hydraulic Structures within Shaft • Contractor interfaces • 11th Street Bridge
CSO-005Site Plan • NPS property • CSA: 0.75 Acres • 12-foot ID shaft; ± 105 feet deep to top of invert • 20-foot long, 4.5-foot ID adit • Diversion Structure • Odor Control and Venting Facility • Internal Hydraulic Structures within Shaft
Poplar PointSite Plan • DDOT property • CSA: 0.80 Acres • Internal Hydraulic Structures within Shaft • Contractor interfaces • Blue Plains Tunnel • Poplar Point Pumping Station Replacement • DDOT South Capitol Street Project.
Contact Us • For more information about today’s presentation, email: • Emanuel Briggs; emanuel.briggs@dcwater.com • For periodic program updates, visit us online at: • www.dcwater.com/workzones/projects/cleanrivers.cfm District of Columbia Water and Sewer Authority 5000 Overlook Ave, SW Washington, DC 20032
Questions? • 011 – March 2012