North System Renewal Water Treatment Plant Project (NSRWTP)

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1 North System Renewal Water Treatment Plant Project (NSRWTP) Presented by: Zack Alabbasi and Andrea Song JTAC Luncheon May 15, 2014

2 History of Moffat WTP

3 History of Moffat WTP David Moffat (July 22, 1839 March 18, 1911) Born in Washingtonville, New York. Moved to Denver in Formed a railroad company in 1867 to link Denver to the national rail network. Denver relied on rivers, ditches and wells until about 1872, when a private water company was franchised. Kassler Plant (first plant) was built in Soon, several water companies were operating in the city. In 1894 they were consolidated as the Denver Union Water Co., headed by Walter Cheesman and David Moffat. The citizens of Denver purchased the company in 1918 for $14 million dollars (bond issue).

4 History of Moffat WTP A vision of David Moffat, the Moffat Tunnel (linking Denver to Salt Lake City and the west coast) was a railroad and water tunnel. Cost $24 million and 28 lives to build. The first train passed through the tunnel in February The 6.2 mile tunnel shortened the distance between Denver and the west coast by 176 miles. Benefits of the Moffat Tunnel as outlined in Nov 1922 issue of Popular Science magazine

5 History of Moffat WTP Moffat Water Treatment Plant 1930s 10 filters 50 MGD capacity

6 History of Moffat WTP Mayor Stapleton commissioning the Moffat Water Treatment Plant in 1937

7 History of Moffat WTP Filter plant 1 (1937): 10 rapid sand filters. Total capacity = 50 MGD Filter plant 2 (1955): 10 rapid sand filters. Total capacity = 75 MGD Filter plant 3 (1974): 8 rapid sand filters. Total capacity = 60 MGD Total capacity = 185 MGD

8 Water Source (Denver Water)

9 Water Source (Moffat WTP) The Upper Williams Fork and Fraser River basin supply Gross reservoir (through the Moffat tunnel) Gross Reservoir Ralston Reservoir Gross reservoir supplies Ralston Reservoir (through South Boulder Creek) Ralston Reservoir supplies Moffat WTP via conduits 16 and 22 Outlet at Gross Reservoir

10 Storage Capacity (Moffat WTP) Gross: 41,811 acre-foot or 13.6 billion gallons Ralston: 10,776 acre-foot or 3.5 billion gallons. Ralston reservoir is 6046 ft. (full) Ralston valve is 5950 ft. Van Bibber is 5840 ft. Moffat is 5623 ft 110 ft 217 ft 96 ft 423 ft = 183 psi

11 Ralston Reservoir Ralston Reservoir Upper Long Lake lower Long Lake

12 Raw Water Transmission Pipes Conduit 16 is 42-inch concrete pipeline constructed in Conduit 22 is 54-inch concrete pipeline constructed in 1950.

13 Treatment Chemicals Aluminum Sulfate (Alum) Potassium Permanganate Calcium Hydroxide (Lime) Carbon Dioxide DADMAC (Cationic polymer) Polyacrlyamide (Nonionic polymer) Sodium Silicofluoride (Fluoride) Sodium Hydroxide (Caustic Soda) Chlorine Ammonium Hydroxide (Ammonia) Coagulation Oxidation ph adjustment Alkalinity, and ph adjustment Coagulation-aid Flocculation-aid, filter-aid and sludge dewatering Fluoridation ph Adjustment Disinfectant Disinfection aid

14 Treatment Process Alum, Lime, Carbon Dioxide, Potassium Permanganate, Polymer Polymer Aeration South Boulder Canal Supernatant/overflow (occasional) Ralston Reservoir Gravity Thickener Supernatant Spent Backwash Gravity Thickener Rapid Mix Backwash Equalization Basin Polymer Spent Backwash Floc/Sed Drain Filter to waste Filter Drain Pump Station Flocculation / Sedimentation Drain Pump Station Polymer, Chlorine Filtrati on Filtration Chlorine, Fluoride, Ammonia, Caustic Soda Disinfection Contact Basin Drying Lagoons (Ralston) Waste Residual Solids Plant drainage, Storm water Dechlor Drain Finished Water Storage Landfill Off-site Disposal Clear Creek Drying Lagoons (41 st & Independence) Distribution System

15 Treatment Process

16 North System Renewal Program

18 Future of Moffat WTP North System Renewal Program: Raw Water Collection System (Gross Reservoir Expansion) Ralston Reservoir Multi-Level Outlet Conduit 16 Replacement North System Renewal Water Treatment Plant Project (NSRWTP)

19 North System Renewal Water Treatment Plant Project (NSRWTP) Rebuild of the Moffat WTP

20 Why Moffat TP? Why Now? Parts of Moffat reaching end of its useful life MOFFAT FILTER GALLERY

21 Why Moffat TP? Why Now? Outdated Technology Mono Media Filtration Current Technology Dual Media Filtration MOFFAT WTP MONO MEDIA MARSTON WTP DUAL MEDIA

22 Moffat WTP Through the Years

23 Road Map for NSRWTP

24 Program Schedule for NSRWTP

25 Plant Site Selection

26 Moffat Site - Property Owned by DW Moffat TP Site ~ 40 Acres YMCA Site ~ 8 Acres

27 Ralston Reservoir Site - Property Owned by DW Ralston Site ~ 1,033 Acres

28 Plant Site Selection Determine the best course of action: MOFFAT SITE? RALSTON SITE? OR

29 Moffat Preliminary Evaluation

30 Moffat Site - Dual Media Filtration Parts of the plant reaching end of its useful life. Outdated filtration technology (mono media filtration). Replace Moffat TP in a planned manner To plan and adjust long range capital budget Consider needs of all stakeholders Evaluation Process: Two locations (Moffat and Ralston) and two treatment technologies are considered in the evaluation (dual-media, membrane, hybrid). Condition Assessment (existing plant), Cost Comparisons (both sites and both technologies), Non-Monetary Criteria (both sites) 250 MGD capacity

31 Moffat Site - Dual Media Filtration Reservoir 3 Reservoir 2 KEY: PHASE 1 PHASE 2 PHASE 3 FUTURE

32 Moffat Site - Dual Media Filtration

33 Ralston Preliminary Evaluation

34 Proposed Construction Site

35 Ralston Site - Dual Media Filtration

36 Ralston Site - Dual Media Filtration

37 The Numbers - Comparison

38 The Numbers - Comparison Moffat 250 MGD Dual Media Ralston 250 MGD Dual Media $370,000,000 Construction Cost 6 Years of Construction ~15,000 Truckloads of material & equipment 108,600 CY Concrete poured 91,500 CY Backfill 85,600 CY Excavation 47,280 CY Concrete demo and crushing $444,000,000 Construction Cost 3.5 Years of Construction ~22,000 Truckloads of material & equipment 178,200 CY Concrete poured 614,000 CY Backfill >1,000,000 CY Excavation 0 CY Concrete demo and crushing

39 Monte-Carlo Analysis

40 Treatment Process Selection

41 North System Renewal Water Treatment Plant Project (NSRWTP) Developing WQ goals for treatment process selection

43 Developing WQ & Treatment Goals for NSRWTP Technical Panel CU, CSU, Mines WRF Wildfire Study Future Uncertainty Gross Reservoir Expansion Extreme weather events Debris in Strontia Springs Reservoir after Hayman Fire 2002 Gross Reservoir at height of drought 2002 Adopted Partnership for Safe Water Goals

45 Storm Event of September 2013 Lessons learned will be incorporated in future plant design standards Ralston Reservoir Flood 2013 Slide Area Auxiliary Spilllway

46 Storm Event of September 2013 Think beyond the WTP Expanding reservoir monitoring program GROSS RESERVOIR Source Water/Distribution System Evaluation

47 Treatment Process Selection for NSRWTP Completing desk-top evaluations and then fast and economical bench-scale tests To help narrow down treatment alternatives for pilot testing

48 Treatment Process Selection for NSRWTP Current Treatment Process Train Watershed Control Strategy Raw Water Intake Coagulant Polymer ph Alkalinity Rapid- Mix & Flocculation Sedimentation Granular Media Filter Fluoride Cl-NH 3 ph Disinfection Corrosion Inhibitor? Finished Water

49 Treatment Process Selection for NSRWTP Future Treatment Process Train Enhanced Coagulation Biological Filtration Fluoride ph Corrosion Inhibitor? Watershed Control Strategy AOP (Peroxide) Coagulant Polymer ph Alkalinity AOP (Peroxide) AOP (Peroxide) Cl-NH 3 Riverbank Filtration Watershed Master Plan Raw Water Intake Precoagulant Ozone Rapid- Mix & Flocculation Sedimentation Settled Water Ozone Granular Media Filter Or UV or Ozone Disinfection Finished Water MF/UF Membrane GAC

Water Water Treatment Plant Tour

Water Water Treatment Plant Tour Don Rankin, Superintendent Topeka, KS 66606 785-368-3111 Tel 785-368-3825 FAX For a complete list of contacts with phone numbers, FAX numbers and email addresses, click