Illicit Discharge Detection and Elimination

Transcription

1 Illicit Discharge Detection and Elimination

2 Outline IDDE Program Administration Outfall Prioritization Dry Weather Sampling Catchment Investigations Wet Weather Sampling Illicit Discharge Elimination Reporting

3 Illicit Discharge Any discharge that is not composed entirely of stormwater Allowable Non- Stormwater Discharges Water line flushing Landscape irrigation Diverted stream flows Rising ground water Uncontaminated ground water infiltration Uncontaminated pumped groundwater Discharges from potable water sources Foundation drains Air conditioning condensation Irrigation water, springs Water from crawl space pumps Footing drains Lawn watering Individual residential car washing Flows from wetlands De-chlorinated swimming pool discharges Street wash waters Residential building wash waters without detergents

4 IDDE Schedule

5 IDDE Program Administration Written IDDE Program Plan Developed within 1 st year Includes: Statement of Responsibility Dry Weather Screening and Sampling Procedure Catchment Investigation Procedure (data sources, inspection methodology, methods to isolate and confirm illicit discharges) Legal authority Existing permittees: should be complete New permittees: developed by 3 rd year

6 IDDE Schedule

7 System Mapping Identifying Outfalls Due within 1 st year Sanitary Sewer Overflows (SSOs) Due with Phase I Mapping (2 nd year) Outfalls to receiving waters Discharges from channelized flow (swales and ditches) Discharges to another system Discharges to your system from another system

8 System Mapping Phase I Due within 2 years All outfalls Municipally-owned BMPs Waterbodies & impairments Catchment delineations Source: MAPC

9 Outfall Catchment Delineations MAPC Method Create digital elevation model (DEM) of municipality Use hydrology toolset to create flow direction & accumulation rasters Create watersheds from flow direction raster and pour points (catch basins) Use catch basin watersheds to create outfall catchments Source: MAPC

10 System Mapping Priority Ranking Problem Outfalls Existing/known issues High Priority Outfalls Discharges to sensitive area Discharge to bacteria TMDL Low Priority Outfalls Excluded Outfalls No potential for illicit discharges Roadway drainage in undeveloped areas Drainage from green spaces & parking Cross country drainage away from sanitary sewer

11 System Mapping Additional Ranking High Priority Outfalls Poor water quality (bacteria and surfactants) TMDLs Old sewer infrastructure Recent sewer conversion Septic systems Define all criteria in IDDE Plan

12 System Mapping Problem Outfalls Set up protocol to collect public complaints or reports of suspected illicit discharges Dry weather screening and sampling not required Begin catchment investigations within first 2 years

13 Dry Weather Sampling Planning Start collecting information Existing record plans/maps Notes on access Traffic management needs Time of year considerations No more than 0.1 inches of rainfall in past 24 hours Spatial planning/schedule with other planned work Educate the public Good PR Private property access

14 Dry Weather Sampling Outfall Access Access Equipment Boots Boats What to do if outfall is inaccessible or not found?

15 Weather Data Weather Underground wunderground.com

16 On-site Rain Gauge

17 Dry Weather Sampling Equipment Needs Water Quality Sampling Field Tests Ammonia Chloride Surfactants Conductivity Salinity Temperature Lab Tests Pollutant of concern E. coli or Enterococcus

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19 Sampling Labs Contest Analytical Eurofins Spectrum Analytical Alpha Analytical ESS Laboratory RI Analytical

20 Dry Weather Sampling Electronic Data Collection

21 Dry Weather Sampling Electronic Data Collection

22 Dry Weather Sampling Things to Look For

23 Dry Weather Sampling All outfalls and interconnections need dry weather inspection within three years of permit effective date Reprioritize outfalls based on dry weather sample results Submit reprioritization with year 3 Annual Report

24 IDDE Schedule

25 Catchment Investigations Develop a written catchment investigation procedure Problem outfall catchment investigations Begin no later than year 2 Complete by year 7 All other catchments investigated based on priority ranking All catchments shall be completed by year 10 Investigate all catchments to determine presence or absence of System Vulnerability Factors

26 System Vulnerability Factors (SVFs) History of SSOs Common twin-invert manholes Common trench construction Sanitary sewer systems crossing over drainage system Sanitary sewer system defects (leaks or cracks) Sanitary sewers with underdrains Inadequate sanitary sewer level of service Former combined sewer areas Widespread septic system failures

27 Catchment Investigations Work from outfall upstream Note condition of all system elements as you go Sample flow found at any junction manhole Develop method for tracking interconnections

28 System Mapping Phase II Developed during & Dry Weather Screening Catchment Investigations Includes Pipes Manholes Catch basins Catchments Municipal sanitary sewer Municipal combined sewer

29 Prioritization & System Vulnerability Factors Prioritization of catchment investigations based on potential for illicit connections System Vulnerability Factors: History of SSOs Common or twin-invert manholes, common trench construction serving storm and sewer alignments Sanitary sewer system crossing over storm drain system Sanitary sewer defects or aging system Areas formerly served by combined sewer systems Catchments where one or more SVF is identified require wet weather investigations at associated outfalls

30 Wet Weather Screenings Required for catchments with a minimum of 1 SVF Follow same procedures as dry weather sampling Sample during storm event with intensity enough to produce stormwater discharge Avoid sampling during first flush of storm event

31 IDDE Schedule

32 What to do if you find an illicit connection Locate, Identify, Eliminate ASAP Narrow down source location between two manholes Identify and confirm source Notify all responsible parties of any illicit discharge Require immediate cessation of improper disposal practices If discharge can t be eliminated within 60 days Develop expeditious schedule for elimination Time between identification and elimination is not a grace period The illicit discharge is unlawful until eliminated!

33 Detection Tools Sandbags in manhole Dye testing TV of pipes Smoke testing If groundwater sources are suspected: Seal pipe connections Investigate groundwater sources & surrounding land uses Continue investigation until all tests are clear Photo source: Stacey DePasquale Engineering

34 Manuals and Tools

35 Standard Operating Procedures SOP 1 Dry Weather Outfall Inspection & Form SOP 2 Wet Weather Outfall Inspection SOP 10 Locating Illicit Discharges SOP 13 Water Quality Screening with Field Kits SOP 15 Private Drainage Connections

36 Reporting Illicit Discharges All sampling results Annual reports should include: Identification date Schedule for removal of discharge Elimination date Complete confirmatory outfall/interconnection screening within one year of removal of all illicit discharges

37 IDDE Program Overview Develop a written IDDE program Regulatory framework (develop or update) Inventory and rank outfalls/interconnections Catchment delineation and investigation Dry and wet weather screenings Develop a complete system map & data management system Identify, track, and remove all illicit discharges

38 Questions?