Flow Monitoring in the Collection System September 11, 2014

Flow Monitoring in the Collection System September 11, 2014 FISHBECK, THOMPSON, CARR, & HUBER INC. Lori Lloyd, PE, LEED AP BD+C

Definitions Why Flow Monitor? Flow Monitoring Applications Site Selection Lessons Learned Agenda

Flow (gpm) DWF Typical daily flow from the system 140 City of Niles Meter 3 18-inch DWF 120 100 80 60 40 20 0 12:00 AM 6:00 AM 12:00 PM 6:00 PM 12:00 AM Weekday DWF Weekend DWF Dry Weather Flow

DWI groundwater entering the sanitary sewer system through indirect paths like at pipe joints and lateral connections Dry Weather Infiltration

Flow (gpm) Rainfall (inches) WWF sewer flows in addition to DWF that occur during a precipitation event 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 City of Ecorse Meter 10-7/27 Event 0 7/27/12 7/28/12 7/29/12 Wet Weather Flow Dry Weather Flow Rainfall 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 Wet Weather Flow

RDII stormwater entering the sanitary sewer system through direct and indirect connections like catch basins, down spouts, and pipe joints Rainfall Dependent Inflow/Infiltration

Measure discharge for billing purposes Establish dry weather flow patterns Quantify and isolate wet weather flow Reasons to Flow Monitor

Credit: Alan Cressler Why Flow Monitor?

Sewage overflows Basements back ups Capacity assurance/ MDEQ compliance Transport and treatment costs Why Flow Monitor?

5/2 5/9 5/16 5/23 5/30 6/6 6/13 6/20 6/27 Flow (MGD) Flow (Gallons per day) Average Monthly Flow (gpd) Rainfall (In) Rainfall (Inches) I/I problem? MORs/WWTP data and lift station data 100 6,000,000 2011 Meridian Lift Station Township Daily Flow City of Flint Monthly Flow WWTP Flows 0.0 1.0 0.00 80 60 5,000,000 4,000,000 2.0 3.0 4.0 0.50 1.00 1.50 2.00 3,000,000 5.0 40 2,000,000 6.0 20 7.0 1,000,000 8.0 0 0 7/1/11 12:00 AM 7/29/11 12:00 AM 8/26/11 12:00 AM 9/23/11 12:00 AM 10/21/11 12:00 AM 11/18/11 12:00 AM 12/16/11 12:00 AM 9.0 Feb Mar Apr May Jun Jul Aug Sep Oct Nov WWTP Raw Data Rainfall Main Flow 2009 Central 2010 Flow Total 2011 Flow 2012 Rainfall 2.50 3.00 3.50 4.00 4.50 5.00 Who Needs to Flow Monitor?

I/I study Flow monitoring Modeling Sewer System evaluation study (SSES) One Step in the Process

Flow monitoring a decision-making tool Collect data used to model collection system Establish DWF patterns Identifying areas with high WWF Flow Monitoring Applications

Flow (gpm) Establish diurnal or seasonal flow patterns 150 Meter 7 12-inch DWF 100 50 0 12:00 AM 6:00 AM 12:00 PM 6:00 PM 12:00 AM Weekday DWF Weekend DWF Dry Weather Flow Patterns Diurnal Curve

Flow (gpm) 400 Saginaw Chippewa Indian Tribe Meter 2 15-inch DWF 350 300 250 200 150 100 50 0 0 5 10 15 20 Weekday Weekend Dry Weather Flow Patterns Casino

Flow (gpm) 2500 City of Flint Meter 9 48-inch DWF 2000 1500 1000 500 0 12:00 AM 6:00 AM 12:00 PM 6:00 PM 12:00 AM Weekday Weekend Dry Weather Flow Patterns Industrial

DWF Patterns Seasonal Variations

Flow (gpm) Rainfall (inches) 4,000 140 City Village of Lincoln of Baldwin Park Meter 23 - - 8/14 5/9 Event 0.0 3,500 120 3,000 100 0.2 0.1 0.4 0.2 0.6 0.3 2,500 80 0.8 0.4 2,000 60 1,500 40 1,000 20 500 1.0 0.5 1.2 0.6 1.4 0.7 1.6 0.8 1.8 0.9 0 2.0 1.0 8/13/12 5/9/14 8/14/12 8/15/12 8/16/12 5/10/14 Wet Weather Wet Weather Flow Flow Dry Weather Dry Weather Flow Flow Rainfall Rainfall Wet Weather Flow Patterns

Flow monitoring process Installation Things to consider Ideal site Site Selection

Area Velocity Measurements Q = A x V V ISCO 2150 d Sigma 910 ISCO LaserFlow Marsh-McBirney Flo Dar Types of Flow Monitors

Monitoring program development Site selection and installation Data collection and handling Data analysis Flow Monitoring Process

Confined space certified personnel needed for installation Proper installation provides for accurate measurements and can prevent malfunctions and data loss Air Monitoring Installation

Program objectives Physical criteria Accessibility Security Budget Site Selection Considerations

Flow (gpm) Rainfall (inches) Meter 6 - Flow Chart 12,000 0 10,000 0.5 8,000 1 FM MH 6,000 1.5 4,000 Ideal 2 2,000 2.5 0 7/1/12 7/6/12 7/11/12 7/16/12 7/21/12 7/26/12 7/31/12 3 Raw Data Rainfall Ideal Site

Ideal Site

Flow (gpm) Rainfall (inches) 400 CSO #003 (24-inch) - Flow Chart 0.00 350 0.50 300 1.00 1.50 250 2.00 200 150 MH FM 2.50 3.00 3.50 100 4.00 50 4.50 Less Ideal 7/5/14 7/6/14 7/7/14 7/8/14 7/9/14 7/10/14 7/11/14 7/12/14 7/13/14 7/14/14 7/15/14 0 5.00 Raw Data Rainfall Less Ideal Site

Less Ideal Site

Where to install flow monitors? Monitor all areas contributing to the WWTP or pump station Monitor areas of suspected high I/I Site Selection

Straight through manhole No other incoming sewers or laterals Adequate depth and velocity Not within the influence of a lift station No surcharging Easily accessible Free of excess grease or debris Ideal Site

Site Selection Lessons Learned

Site hydraulics Lift station Site access Grease/debris Site Selection Lessons Learned

Flow (gpm) Rainfall (inches) 1,600 Meter 8 - Flow Chart 0 1,400 0.5 1,200 1,000 1 800 1.5 600 400 2 200 Sensor 0 7/8/12 7/10/12 7/12/12 7/14/12 7/16/12 7/18/12 7/20/12 2.5-200 3 Raw Data Rainfall Multiple Incoming pipes

Ideal Site?

Flow (gpm) Rainfall (inches) Meter 4 - Flow Chart 500 0.00 450 0.20 400 0.40 350 0.60 300 0.80 250 1.00 200 1.20 150 1.40 100 Sensor 1.60 50 1.80 0 2.00 4/11/14 4/12/14 4/13/14 4/14/14 4/15/14 4/16/14 4/17/14 4/18/14 4/19/14 4/20/14 4/21/14 Raw Data Rainfall Low Depth

Flow (gpm) Rainfall (inches) Meter 1 WWTP 2,500 0.00 2,000 0.50 1.00 1,500 1.50 1,000 2.00 500 Sensor 2.50 0 3.00 5/6/14 5/11/14 5/16/14 5/21/14 5/26/14 5/31/14 6/5/14 6/10/14 6/15/14 6/20/14 Raw Data 2 Rainfall Low Velocity

Flow (gpm) Rainfall (inches) 400 Meter 11 - Flow Chart 0 350 0.1 300 0.2 0.3 250 0.4 200 0.5 150 0.6 100 0.7 0.8 50 0.9 0 1 7/20/12 7/21/12 7/22/12 7/23/12 7/24/12 7/25/12 7/26/12 7/27/12 7/28/12 7/29/12 7/30/12 Raw Data Rainfall Lift Station Influence

Flow (gpm) Rainfall (inches) 5,000 Meter 4-4/15 Event 0.0 4,500 0.1 4,000 0.2 3,500 0.3 3,000 0.4 2,500 0.5 2,000 0.6 1,500 0.7 1,000 0.8 500 0.9 0 1.0 4/14/12 4/15/12 4/16/12 4/17/12 4/18/12 4/19/12 4/20/12 4/21/12 Wet Weather Flow Rainfall Lift Station Influence

Accessibility

Accessibility

Accessibility

Accessibility

Accessibility

Accessibility

Accessibility

Accessibility

Accessibility/Security

Flow (gpm) Rainfall (inches) Meter 11 - Flow Chart 2,500 0.00 0.20 2,000 0.40 0.60 1,500 0.80 1.00 1,000 1.20 1.40 500 1.60 1.80 0 12/7/12 12/12/12 12/17/12 12/22/12 12/27/12 1/1/13 1/6/13 2.00 Raw Data Rainfall Silt Covering Sensor

Silt and Seasonal Variation

Flow (gpm) Rainfall (inches) Meter 7 - Flow Chart 600 0 0.1 500 0.2 400 0.3 0.4 300 0.5 0.6 200 0.7 100 0.8 0.9 0 2/1/12 2/3/12 2/5/12 2/7/12 2/9/12 2/11/12 2/13/12 2/15/12 2/17/12 1 Grease on Sensor

Credit: Bill Lackey Ideal Site?

Know the objectives of your flow monitoring program Allow enough budget and time to collect necessary data Work closely with field staff when picking sites Flow vary greatly between systems and seasons Careful site selection can save time and money Conclusions

Thank You Questions? FISHBECK, THOMPSON, CARR, & HUBER INC.