Innovative Improvements to a 53-Year Old Water Plant for HABs, Crypto, and Whatever Else the Maumee River Brings

Transcription

1 Innovative Improvements to a 53-Year Old Water Plant for HABs, Crypto, and Whatever Else the Maumee River Brings Robert T. Shoaf, P.E., BCEE AECOM (Columbus, Ohio) Scott Hoover, Plant Superintendent Napoleon, Ohio

2 Presentation Summary Introduction Napoleon s Current Water Plant Water Quality (Maumee River and Wauseon Reservoir) Initially Proposed Process vs. Final Proposed Processes / Jar Testing Proposed Strategy for Treating Source Architectural Concepts Schedule / Funding

3 Napoleon, Ohio Population: Approximately 9,000 Provides Water to Several Satellites Including: Florida Liberty Center Malinta (and McClure) Henry County Regional Water District Some other areas Water Treatment Plant: 4.5 MGD Lime Softening with Miex pretreatment Average Demand: 1.36 MGD Ohio EPA Orders for Additional Treatment for Cryptosporidium Water Met All Water Quality Standards at Plant Satellite Systems Had THM Concerns

4 - Existing Plant

5 Raw Water Source Maumee River Napoleon, Ohio Tributaries Include: Auglaize River, Blanchard River, St Marys, Tiffin River

6 Water Quality Varies Tremendously Maumee River Water Quality Water Quality Data from USGS upstream of Napoleon ( ) plus Other Estimated Values Constituent Units Min Average Max Iron mg/l Manganese mg/l Alkalinity mg/l as CaCO Conductivity us/cm Hardness mg/l as CaCO Nitrate mg/l Turbidity NTU TOC mg/l City has Bin 2 Designation due to Raw Water Crypto Sampling Occasional Microcystin Detects in Raw Water Wauseon Reservoir Helps in Many Ways, Hurts with HABs (but still rel. low)

7 Original RFP Was Issued To Design the Following Processes: 1. Pretreatment Solids Contact Upflow Clarifiers 2. Upgrade Lime Softening Process 3. Upgrade Chemical Feed 4. Upgrade Gravity Filters 5. Filter to Waste 6. UV Disinfection 7. Granular Activated Carbon (GAC) Contactors 8. Second Clearwell

8 Existing Chemical Feed Systems Existing Chemical Feed Equipment is Original and Parts No Longer Available City Wanted to Remove Chlorine Gas Due to Safety Concerns

9 Original GAC UV Option

10 Alternative Options: Lime and GAC vs. Reverse Osmosis Membranes TABLE 13 COMPARISON OF CAPITAL AND OPERATIONAL COSTS OF ALTERNATIVES Alternative 1 - Lime Softening - Conv. Filtration - GAC Alternative 2 - Conv. Sedimentation - Conv. Filtration - RO (NF) Softening Alternative 3 - Conv. Sedimentation - UF Membranes - RO (NF) Softening Lime-Soda Softening Capital $165,000 $0 $0 Costs Conventional Gravity Filter $648,150 $648,150 $0 Upgrade Costs GAC Equipment Capital Cost $3,463,000 $0 $0 NF Membrane Softening $0 $3,295,000 $3,295,000 Capital Cost Ultrafiltration Membrane $0 $0 $2,965,000 Add'l Capital Cost Total Capital Cost $4,276,150 $3,943,150 $6,260,000 Lime-Soda Softening Annual $108,836 $0 $0 Costs (including sludge and CO 2 ) GAC Annual Cost $336,800 $0 $0 Membrane Softening Annual $0 $331,000 $331,000 Cost UF Membrane Additional $0 $0 $225,000 Annual Cost Total Annual Cost $445,636 $331,000 $556,000 Total Present Worth $10,300,000 $8,400,000 $13,800,000 Relative Cost (Capital and Middle Lowest Highest Annual Operating)

11 Alternative Process (RO) UV

12 (Red Indicates Additional / Revised) 1. Upgrade Raw Water Intake (VFDs, Control Valves) 2. Pretreatment Basins 3. Modify Existing Miex Process as Pretreatment 4. Add Significant PAC Improvements (Algal Toxin Concerns) 5. Upgrade Gravity Filters New Underdrains / Deeper Media / Filter to Waste 6. New Filter Influent / Effluent Valves / Actuators 7. Lime Softening Improvements 8. New RO Membrane Process (Softening and TOC Removal Process plus removes contaminants from river) 9. Granular Activated Carbon Contactors 10. Convert to Sodium Hypochlorite (eliminates chlorine gas) 11. UV Disinfection (Added for Ohio EPA Orders) 12. New High Service Pumps

13 Jar Testing Results for Turbidity ACH shows promise

14 Jar Testing Results for TOC Reduction ACH shows promise

15 Partial Strategy for Treating Variable Source 1. Convert Existing Miex Process to Pretreatment (but not expecting to get toolbox credits). 2. Switch Coagulant from Alum to ACH. a) Pretreatment Feed (for turbidity and TOC reduction) b) Secondary Feed Prior to Sed. Basins (for turbidity and TOC reduction) c) In-line Rapid Mixing 3. Add Sodium Permanganate Feed System (to satisfy demand) 4. Significantly Upgrade PAC Feed (for HABs) 5. Monitor and Pace Permanganate Feed off of downstream ORP AND Hach Cl17 (which can also measure permanganate residual) 6. Install City-Owned Streaming Current Monitor (for monitoring only now) 7. Convert Horizontal Flocculators to 4-Stage Vertical Flocculators 8. Add Plate Settlers 9. Upgrade Filters

16 Existing MIEX Process to be Modified

17 Existing Floc / Sed Processes to be Modified

18 Sedimentation Improvements with Plate Settlers

19 Existing Filters to be Upgraded Replace Filter Pipe Gallery Valves Provide New Filter Media (Anthracite Sand) Replace Wheeler Bottoms with New Underdrains Existing Media: 30-inch Monomedia 36-inches of Media 21 inches anthracite 15 inches sand L/D 10 > 1,250

20 Cryptosporidium Removal / Inactivation Options Conventional Treatment IF Rapid Mix Flocculation Sedimentation Sand Filtration <0.15 NTU GAC Filter UV Disinfection Clearwell To Distribution + 3-log log log log log Cumulative Log Credit for Crypto Removal Inactivation Bin 1 Bin 2 Bin 3 Bin 4

21 UV Disinfection Project (Completed Dec 2016): - Included New High Service Pumps / UV Reactors Requested / granted 3-log credit for both Crypto and Giardia Allows bypass of main clearwell (for maintenance, etc.) with virus inactivation acheived in much smaller wet well (new). Uncommon arrangement being downstream of clearwells. Existing High Service Pump Station was Constructed BEFORE the Plant and Requires a Priming System to Operate at Low Clearwell Levels

22 RO to Replace Lime And MIEX Membranes to Eliminate Lime Softening Membranes also Eliminate Miex (TOC) Membranes also Can Remove Nitrates, Atrazine, and Other Constituents of Concern in Maumee River

23 - Proposed Process

24 Architectural Concept Previous Plant (Demolished in 1960 s and 1990 s) Current Plant (Brick) with Metal Building (Houses Miex Pretreatment)

25 Initial Concept (Draft) Design Option

26 Current Concept New Building

27 Final Rendering

28 Progress Photo July 13, 2017

29 Progress Photo September 14, 2017

30 Progress Photo September 14, 2017 U V New Clearwell (virus inactivation only)

31 April 2018 Projected Start-Up Membrane Design includes: 2 Skids 18:9, 7M (2 Stage) Loose NF Membranes [TOC, Hardness] 2 Skids 18:9, 7M (2 Stage) Tight NF/RO Membranes [Nitrates, Atrazine, etc]

32 Construction Schedule UV Improvements Project Completed 2016 WTP Project Bid: March 1, 2017 Notice to Proceed: May 3, 2017 Construction Start: June 1, 2017 Projected Membrane Start-up: April 2018 All Equipment Start-up: October 2018 Construction Completion: December 2018

33 Project Summary Two (2) Phase Project: - Phase 1: UV Disinfection Improvements, New High Service Pumps, SCADA (COMPLETE) $1.4 million - Phase 2: Water Plant Improvements (PROJECT UNDERWAY) $14 million

34 Funding Package While Construction Costs Have Gone Up slightly over Time, Actual Cost Impacts to Users Has Gone DOWN! City and AECOM Applied Aggressively and Creatively for Funds through Ohio EPA Drinking Water Assistance Fund Achieved: $2,900,000 Principal Forgiveness (GRANT)! Balance: Subsidized 30-year interest Loan (0% Interest)

35 Summary Napoleon s Water Treatment Plant is Getting a Facelift and Water Quality is Improving Reverse Osmosis will be Providing Softening AND Organics Removal Significant Additional Infrastructure Improvements Now Included: High Service Pumps (Replaced with New) Algal Toxin Treatment UV Disinfection More Valve Replacements More Efficient Heating / Cooling Systems Reverse Osmosis Membrane Process Protects Residents from Future Contaminants Found in River

36 Questions? Rob Shoaf (614) office (614) cell Robert T. Shoaf, P.E., BCEE Scott Hoover