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System Characterization and Monitoring Activities. Adrienne Nemura, P.E. Limno-Tech, Inc. Three Components of System Characterization. Physical characterization: What are the components of the CSS? How does the CSS respond to rainfall? Characterization of combined sewage and CSO
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System Characterization and Monitoring Activities Adrienne Nemura, P.E. Limno-Tech, Inc.
Three Components of System Characterization • Physical characterization: • What are the components of the CSS? • How does the CSS respond to rainfall? • Characterization of combined sewage and CSO • What significant pollutants are present in CSO? • Characterization of receiving waters • Are CSOs likely to cause WQ standards violations? System Characterization and Monitoring Activities
Physical Characterization System Characterization and Monitoring Activities
Physical Characterization • Typically includes: • Delineation of CSS area and sewersheds • Locating CSO outfalls, regulator structures, the WWTP, and pump stations • Estimating land use and impervious cover, by sewershed • Showing layout of major interceptors • Identifying hydraulic capacities for the WWTP, CSO regulators, and pump stations • Identifying CSO receiving waters System Characterization and Monitoring Activities
Physical Characterization of Springfield, USA System Characterization and Monitoring Activities
Overview of Collection System • Layout of major interceptors • Location of: • WWTP • CSO regulators • Pump station WWTP System Characterization and Monitoring Activities
CSO Area CSO Area #2 (250 acres) Lazy River CSO Area #1 (300 acres) CSO #1 CSO #2 CSO Area #3 (150 acres) Babbling Brook CSO #4 Pump station relief CSO #3 Defining Sub-Sewershed Areas 7 System Characterization and Monitoring Activities
Characterizing Land Use • General land use and estimated impervious cover • Some data available from USGS http://edc.usgs.gov/products/landcover/lulc.html#description • Land use categories include: • Parkland or open space (<5% impervious) • Low density development (5-35% impervious) • Medium density development (35-70% impervious) • High density development (>70% impervious) System Characterization and Monitoring Activities
High Density Medium Density Low Density Open Space 9 System Characterization and Monitoring Activities
Tabulating Land Use System Characterization and Monitoring Activities
Impervious Cover Calculation Example:CSO Area #1includes: System Characterization and Monitoring Activities
Pipe, Capacity, & Flow Information • Hydraulic analysis should be sufficient to: • Establish capacities for WWTP, pump stations and CSO regulators • Quantify dry weather and wet weather flows, including flows to CSS from neighboring communities • Describe any existing flow metering • Permanent system meters and monitors such as SCADA (Supervisory Control And Data Acquisition) • Metering/flow monitoring from previous studies • Identify problem areas and bottlenecks System Characterization and Monitoring Activities
Springfield: Pump Station and WWTP Capacities (MGD) System Characterization and Monitoring Activities
SpringfieldCSS Capacities (MGD) System Characterization and Monitoring Activities
Springfield Hydrologic Flow BalanceQwet = CiA C = runoff coefficient (% imperviousness) i = rainfall intensity A = area System Characterization and Monitoring Activities
Springfield Hydrologic Flow BalanceQwet = CiA System Characterization and Monitoring Activities
Problem Areas and Bottlenecks • Compare capacity at key locations in the collection system with peak wet weather flow rates • Intersections of major interceptors • Regulators • Pump stations • Cross connections • Additional study may be required in areas that often flood during wet weather System Characterization and Monitoring Activities
Example—Bottleneck • Pump station capacity should equal or exceed capacity of interceptors delivering flow From CSO #2 Max. flow = 2 MGD P.S. capacity 6 MGD to WWTP From CSOs #1 and #3 Max. flow = 5.5 MGD System Characterization and Monitoring Activities
Example: System Characterization for Monticello, IN (Pop=5,723) • 32 miles of sewer (60% CSS) • 13 sub-sewersheds; 5 CSOs; 8 PS; 1 WWTP; 1 rain gage (at WWTP) • Developed XP-SWMM model • Calibrated to flow meter data from Apr 1 – May 30, 2001 • Scenarios evaluated using an average and peak year (0 overflows) System Characterization and Monitoring Activities
Characterization of Combined Sewage and CSO System Characterization and Monitoring Activities
Characterization of Combined Sewage and CSO • Sources of existing information: • General WWTP operating data • Discharge monitoring reports (DMRs) • Pretreatment program data (SIUs) • Facility planning studies • GIS databases • Other local CSO studies • Literature System Characterization and Monitoring Activities
Characterization of Combined Sewage and CSOs • LTCP should include estimates of central tendency (median, EMC) and ranges of concentration for potential pollutants of concern • Most often: Bacteria, TSS, BOD • Sometimes: Nutrients • Less often: Metals and toxics System Characterization and Monitoring Activities
Average Pollutant Concentrations in Municipal Discharges Source: Report to Congress on the Impacts and Control of CSOs and SSOs System Characterization and Monitoring Activities
Average Pollutant Concentrations in Municipal Discharges Source: Report to Congress on the Impacts and Control of CSOs and SSOs System Characterization and Monitoring Activities
Average Pollutant Concentrations in Municipal Discharges Source: Report to Congress on the Impacts and Control of CSOs and SSOs System Characterization and Monitoring Activities
Characterization ofReceiving Waters System Characterization and Monitoring Activities
Characterization of Receiving Waters • LTCP should document the following: • Flow conditions in the CSO receiving water(s) • Water quality standards (WQS), including designated uses, for each CSO-impacted water • Available water quality, sediment, and biological data • Known impairments • Location of sensitive areas • Planned or ongoing TMDL studies System Characterization and Monitoring Activities
Example Summary of Flow Conditions System Characterization and Monitoring Activities
Example Summary of Flow Conditions 31 System Characterization and Monitoring Activities
SpringfieldExample WQS: Designated Use • Lazy River • Boating and Canoeing – Activities in which limited contact with water is assumed • Protection of Aquatic Life – Conditions allowing maintenance of a wide variety of warm-water biota • Babbling Brook • Whole-Body-Contact Recreation – Activities in which there is direct human contact to the point of complete body submergence • Cool-water Fishery – Maintenance of a sensitive, high-quality sport fishery System Characterization and Monitoring Activities
SpringfieldExample WQS: Numeric Criteria • Lazy River • Fecal Coliform- For the recreational season (April 1 – Oct 1), shall not exceed 5,000 MPN/100mL in more than 10% of the samples • Dissolved Oxygen – daily minimum 4.0 mg/L year-round • Ammonia – acute and chronic criteria that are temperature and pH dependent • Babbling Brook • Fecal Coliform – For the recreational season (April 1 – Oct 1) geometric mean cannot exceed 200 MPN/100 mL • Dissolved Oxygen – minimum daily 5.0 mg/L • Ammonia – more stringent than for Lazy River System Characterization and Monitoring Activities
Fecal Coliform: Apr-Oct, 2003 System Characterization and Monitoring Activities
Monitoring 35 System Characterization and Monitoring Activities
Monitoring Program • Builds on the system characterization • Designed to obtain missing, but necessary, information about the CSS operating conditions and CSO impacts • Supports implementation of both the NMC and an LTCP System Characterization and Monitoring Activities
MonitoringGoals and Objectives • Typical objectives: • Define hydraulic response of the CSS to rainfall • Determine CSO impacts on receiving water(s) • Evaluate effectiveness of the NMC • Establish baseline conditions for comparison with anticipated improvements due to implementation of the LTCP System Characterization and Monitoring Activities
Monitoring – Data Needs • Data needs are very site specific • Link to short and long-term control objectives • Data needs are dependent on the amount of existing information available • Prioritize as data needs are typically greater than available budget • Monitoring should be conducted in a manner consistent with applicable state WQ standards System Characterization and Monitoring Activities
Monitoring – Sampling Program • Types of monitoring: • Rain gage • CSS flow • Dry weather • Wet weather • CSO volume, frequency and pollutant concentrations • Receiving water monitoring • Upstream • CSO impacted zone System Characterization and Monitoring Activities
Monitoring – Sampling Program • Sampling parameters: • Flow • CSO effluent and receiving water quality • Bacteria, TSS, BOD • Nutrients (if needed) • Metals and toxics (if needed) • Continuous vs. discrete event monitoring System Characterization and Monitoring Activities
Monitoring Location Considerations • Physical logistics and budget • Flow patterns and spatial variability between with storms • Pollutants of concern; location of sources • Location of sensitive areas System Characterization and Monitoring Activities
Example of Rainfall Variability 8/10 – 8/12/01 Radar Rainfall Estimates 42 System Characterization and Monitoring Activities
SpringfieldScreening Potential CSS Monitoring Locations 43 System Characterization and Monitoring Activities
Block test location Electronic meter location WWTP SpringfieldExample CSS Monitoring Locations Rain gage location Rain gage at local airport System Characterization and Monitoring Activities
Monitoring—Sampling Program • Information to be documented: • Duration of monitoring program • Monitoring locations • Frequency of sampling; number of events sampled • Pollutants or parameters analyzed • Sampling protocols, equipment used and analytical methods System Characterization and Monitoring Activities
Example Block Test Results System Characterization and Monitoring Activities
Electronic Meter Results: Data 47 System Characterization and Monitoring Activities
Electronic Meter Results: Plot 48 System Characterization and Monitoring Activities
Summary • System Characterization • Characterization of physical components of CSS • Characterization of combined sewage and CSOs • Characterization of receiving waters System Characterization and Monitoring Activities
Summary • Monitoring • Track frequency, duration, flow rate, volume and pollutant concentration of CSO discharges • Evaluate impacts of CSOs on the receiving water System Characterization and Monitoring Activities