Mayo Sewer System. Chris Phipps, P.E., Director Jia Liu, Acting Utility Administrator, Central Maintenance Victor Kibec, Senior Engineer

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1 Mayo Sewer System Chris Phipps, P.E., Director Jia Liu, Acting Utility Administrator, Central Maintenance Victor Kibec, Senior Engineer Department of Public Works

2 History of Mayo Service Area Geographical Location Mayo Septic System Take Over Capital Improvements Projects

3 Geographical Location East of Glebe Bay and Bordered by the South and Rhode Rivers

4 Cause for Concern 1975 Survey by AA DOH reported 20% of homes surveyed had failing septic systems Population in 1975 was reported at 6,900 Population projected to increase to 17,000 by 2020 (w/o high density Beverly-Triton Beach) Population projected to increase to 27,000 by 2020 (with high density Beverly-Triton Beach) Population per 2017 Water and Sewer Master Plan, 2015 at 8,700 January 1974 Application for a sewer outfall permit submitted to EPA for approval

5 June 17, 1974 Letter of Support to DNR & EPA I speak in support of the application by the Anne Arundel County Department. In fact I, and the majority of the people living on the Mayo Peninsula, rejoice at the application, for it means that we re really close now to getting a public service we ve been asking for, praying for, and promised, for years now. John R. Auchubon President Beverly Beach Community Association Also representing Mayo Civic Association

6 Original Treatment Consideration Collection System: Septic Tank Effluent Pump (STEP) system Liquids convey to treatment plant for processing Solids retained in septic tank and pumped out periodically by the County Treatment Plant: Centralized Water Reclamation Facility Based on Innovative and Alternative design criteria EPA Grants Process Recirculating Sand Filters for organic matter removal Bullrush and Cattail Wetlands for nitrogen removal Peat Wetlands for phosphorus removal Ultra-violet light for final disinfection prior to discharge to Rhode River

7 Original Treatment Design Criteria MG/L LBS/Year TONS/Year Suspended Solids 15 24, Total Nitrogen , Total Phosphorus Original System Construction Cost: Over $63 million As I/A System EPA grants funded $45 million

8 - 30 Years Later - Original plant of capacity New Enhanced Nutrient Removal requirements required new modern treatment system Natural treatment process not reliable; unable to produce high quality effluent Annapolis WRF already had ENR improvements underway Most affordable and reliable alternative; pump to Annapolis WRF for treatment Avoided another outfall into Rhode River

9 Overall Project

10 Rhode River WRF discharge eliminated entirely from Rhode River Pollutant loads removed entirely Nitrogen - 12 tons annually Phosphorus 0.5 tons annually Suspended Solids 12 tons annually Equivalent Impervious acreage treated 500 to 3,000 acres Monitoring program underway with Anne Arundel Community College (AACC) to measure efforts (pre/post discharge)

11 Mayo Septic System Take Over Design Focus Address Environmental and Health Concerns Selection of the System (Factors Considered) Topography, Ground water levels Minimal construction impacts to residents and environment (shallower excavation and shorter construction duration) Construction Collection systems, Pumping Stations, Wastewater Treatment plants Convert individual septic systems Master Easement

12 Easements Original Master Easement New Mayo Tank Easement

13 What Have We Done Since the Takeover Infiltration and Inflow Study Smoke testing Physical tank inspections Flow meters installations at pumping stations and gravity manholes Major Pumping Stations and Force Main Replacement Projects Replacing pumps Installing back up generators Updating electrical and instrumentation controls

14 Traditional Septic System vs. Mayo Septic System Traditional Septic System: Waste flows to septic tank Sludge falls to the bottom Scum floats to the top (greases, fats, oils) Watery waste (effluent) flows to the drain field Solids pumped out of the septic tank Septic Tank Effluent Pump (STEP) System Abandoned drainage field Replaced septic tank with Mayo Tank Installed discharge line from Mayo Tank to sewer

15 How Does the Mayo Septic System Work? Septic Tank Effluent Pump (STEP) System Waste flows into Mayo Tank Mayo Tank functions the same as a traditional septic tank Solids settle to the bottom Based on elevation, liquids are conveyed to sewer mains by gravity or pump Difference No drain fields

16 Mayo Tanks (Gravity Vs. Pressure)

17 Mayo Septic Tank System Details Private and Public Mayo Tanks Publicly owned and maintained (3,381 tanks) Privately owned and maintained (55 tanks current inventory log) Publicly Owned Mayo Tanks Private Part Pipe from house to Mayo Tank Public Part Mayo Tank to right of way and control panel Why to determine if public/private Emergency / Mayo Tank Pump out Emergency Services

18 Above Ground What Is in My Yard? Tank Cover (Gravity and Pressure Tanks) Must be 6-8 above grade (not sealed) Clean Out (Gravity and Pressure Tanks) 6 tank access for cleaning 4 house drain line access Pressure Tank Only Junction Box wire connection point Control Panel/Alarm Box Red Button high water when light. Push to silence. Black alarm speaker On house w/ direct tank line of sight Disconnect box main breaker for power

19 Underground What Is in My Yard? Tank (Gravity and Pressure Tanks) High Density Polyethylene Prior Fiberglass or concrete Riser (Gravity and Pressure Tanks) Underground pipe (Gravity and Pressure Tanks) For Pressure Tanks (only) Pump basket Pump 3 Floats (on/off/high) Power and float cables Check valve Service valve (shut-off valve) Underground wires

20 Mayo Tank Maintenance Asset Management and Work Order System Records of each Mayo Tank Mayo Tank Pump Out Program All public tanks are in regular maintenance pump out program 24/7 Mechanical Technician Standby Emergency response Private Homeowner responsible Regular pump out and repair by licensed contractors

21 Owner s Role Maintain Open Access Don t place shrubs, fences, etc. in easement (keep open access) Prevent System Clogging Put only human waste and toilet paper into sinks, toilets, or drains If the Alarm Sounds May be due to power loss, tripped breaker, force main break, sensor, etc. Stop using water to prevent overflow. Press the red button to silent the alarm (light will remain on). Note: Using a lot a water at once can cause an alarm. If this is the case, the alarm will correct itself in about 15 minutes. If light is still on after 15 minutes, call Emergency Services at If the property owner observes non-emergency problems (cracked cover, etc), contact Emergency Dispatch at

22 Bureau of Utility Operations 24-Hour Emergency Water Services: (410) Billing Inquiries: (410) Bureau of Highways Northern District: (410) Central District: (410) Southern District: (410) Traffic Lights/Signs: (410) Bureau of Waste Management Services Bulk Trash Service/Curbside Collections: (410) Bureau of Engineering General Inquiries: (410)