1. 11 Development of Retention Treatment Basin for the Treatment of CSOs in Windsor, Ontario, Canada Canada-Mexico Water Workshop March 30, 2010

2. 2 Background:

3. 3 The Detroit River is about 51.5 km in length. It drains 181,300 hectares in Michigan and Ontario; as well as sewer-shed areas. Detroit River Basin:

4. 4 Detroit, Michigan (www.geology.com)

5. 5 Windsor, Ontario

6. 6 CSO in Windsor The Riverfront Interceptor Sewer intercepts flows from combined sewers and conveys to the Lou Romano Water Reclamation Plant (LRWRP) for treatment. LRWRP Windsor CSO Study Area Riverfront Interceptor Sewer

7. 7 September 7/8, 2009 September 12, 2009 ( Pelee Island, Westshore) Summer 2002

8. 8 Pollution from CSOs

9. 9 Steps and MOE Guideline A Remedial Action Plan (RAP) has been developed to address water quality concerns in the Detroit River Basin. One of the main priorities of RAP is to control and reduce pollution from CSOs. The Ontario Ministry of the Environment (MOE) promulgated Procedure F-5-5 as a means of documenting its objectives for CSO control.( ~ Primary Treatment)

10. 10 MOE – Procedure F-5-5 Procedure F-5-5 specifies that:  90% of wet-weather flow is to be treated to primary treatment equivalency, which is defined as a seasonal average of at least » 50% removal of TSS and » 30% removal of BOD 5.

11. 11 A Conventional Retention Treatment basin (CRTB) or a Storage Chamber for controlling CSOs was suggested. For the storage option (i.e., capture and store - no allowance for treatment), the Storage Chamber volume was calculated to be approximately 106 million gallons (400,000 m 3 ). Originally Proposed Solution

12. 12 Issues that Require Solutions Not enough space for CRTB or Storage Chamber on the Windsor riverfront. CSOs contained high proportion of solids with poor settleability. CRTB or Vortex Separators were unable to meet MOE Procedure F-5-5. Therefore, an effective treatment technology that requires a small foot-print is required for CSO control.

13. 13 MOE – Procedure F-5-5  Furthermore, the seasonal average TSS concentration in the effluent of a treatment system should not exceed 90 mg/L for more than 50% of the time for an average year during the seven-month period commencing within 15 days of April 1.

14. 14 Approach A high-rate Retention Treatment Basin (RTB) with chemical coagulation was identified as the preferred approach for CSO treatment. However, additional information were needed to determine if a high-rate RTB combined with chemical coagulation could be designed for the site that would:  Have a small enough footprint, and  Meet the requirements of the MOE Procedure F-5-5.

15. 15 Establish the feasibility of using a high-rate RTB in treating Windsor CSO employing coagulation ( with coagulants, such as polymers). Establish the characteristics of CSOs Run batch and pilot plant studies Establish removal efficiencies for pollutants from the CSOs at various surface overflow rates (SORs) Establish operating conditions and sludge management Approach (contd..)

16. 16 Scope Settling Column Tests  Evaluate settling characteristics of solids with and without chemical addition  Determine appropriate type of polymer and its required dosage based on Jar Test results Design and construct a Pilot-plant to be used as High Rate RTB Verify performance characteristics Develop design parameters for the full scale RTB Carry out CFD Study to:  Determine the size and geometry of the RTB  Finalize Inlet and Outlet arrangements

17. 17 S CHEMATIC D IAGRAM OF THE S ETTLING C OLUMNS S ET - UP Settling Column Tests J AR T EST

18. 18 The pilot plant of the RTB was constructed at the LRWRP. CSO was pumped from the influent channel of the grit chamber at the LRWRP. Pilot-Scale Setup

19. 19 Pilot-Scale - Overview

20. 20 0.30 0.65 0.30.2 0.8 0.40 0.20 0.40 0.65 0.45 0.1 0.40 1.40 0.4 Perforated baffle Movable baffle Influent channel Outlet baffle Influent Adjustable weir plate (V-notches and launder) Adjustable weir plate (V-notches) Outlet zone Outlet pipe Effluent box (width 0.24 ) Outlet pipe (200 mm) Launder B x H = 0.08 x 0.50 Settling zoneInlet zone 3.0 0.3 0.6 Flushing Box Drain Retention Treatment Basin (RTB) The pilot plant including the RTB was designed to operate at high surface overflow rate, up to 1440 m 3 /m 2.d (60 m/h).

21. 21 The RTB and the Flushing Box arrangement

22. 22 Operating conditions Two types of cationic polymers were tested (ZETAG) The RTB were tested for surface overflow rates (SOR) ranged from 6 m/h to 57 m/h. The performance of the RTB were evaluated by analysing multiple samples for each run The samples were analyzed for:  TSS  BOD  TKN  TP

23. 23 Polymer Dosage vs TSS removal

24. 24 Polymer Dosage vs BOD removal

25. 25 Optimum Polymer Dose – Percentage of Time Effluent TSS < 90 mg/L

26. 26 Predicted Flow and solids deposition patterns in model of pilot high-rate RTB with a steep bottom slope

27. 27 Comparison of Pilot RTB with CFD Model in TSS removal

28. 28 Full-Scale Design of the High Rate RTB Based on the pilot-scale RTB tests and CFD simulation results, it is suggested to design the full-scale RTB facility using a design SOR of 12,000gpd/ft 2 (20 m 3 /m 2 hr). (Conventional RTB basin is typically sized with typical design SORs of 1,200-3,000gpd/ft 2 (2-5 m 3 /m 2 hr). Therefore, the high-rate RTB will only need to be approximately 10-25% of the size of a conventional RTB.

29. 29 Schematic Flow Diagram

30. 30 High Rate RTB – General set up

31. 31 Top View of the High Rate RTB

32. 32 Proposed High Rate RTB Site Proposed RTB Facilities Integrated with the Existing Riverfront Facilities

33. 33 Acknowledgement Dr. Jian Li, Stantec Dr. Ahmed El-Gendy, Assoc. Prof. Ain-Sham University, Egypt Dr. Alex McCorquodale, Professor, UNO Mr. Harold Hornec, Stantec Mr. Ken Ferguson, Ontario Ministry of the Environment Mr. Paul Drca. City of Windsor Mr. Kit Woods, City of Windsor Dr. Jerry Marsalek, Environment Canada Mr. David Avril of Questor Veritas Inc Many other graduate and undergraduate students

34. 34 THANK YOU

35. 35 The TSS concentration in the influent CSO ranged from 180 mg/L to 300 mg/L, compared to a mean value of 150 mg/L for raw sewage. The average BOD concentration in the influent CSO was found to be around 100 mg/L. This is compared to a mean value ranged from 140 mg/L to 195 mg/L for raw sewage. Influent Characteristics

36. 36 Inlet Zone Settling Zone Outlet Zone Sludge Zone RECTANGULAR SETTLING BASIN

37. 37 L L H B Raw waste water Q Q L = length B = width H = depth 1)inlet zone 2)settling zone 3)outlet zone 4)sludge zone sludge Top View Type 1 Settling V f = L V o H V f = Q. V o B H V o Q = L B H V o H V o = Q. B L Surface loading rate = Q / A = Q / (B x L) = V o 2 1 34 VfVf VoVo Clarified water Sectional View