July 26, 2018 ACWA Bend, Oregon. Jamie Hughes & Leila Barker Regulatory Affairs Department

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1 Multi-Objective Natural Treatment Systems How Clean Water Services Forest Grove NTS Solved Several Water Quality Challenges and Created Habitat and a Community Amenity July 26, 2018 ACWA Bend, Oregon Jamie Hughes & Leila Barker Regulatory Affairs Department

2 Outline Clean Water Services Why a Natural Treatment System at CWS? Overview of Fernhill NTS Pilot Study and Results Full Scale Design Triple Bottom Line What s Next

3 Clean Water Services Public utility district that specializes in water resources management. Serves nearly 600,000 residents inside the urban growth boundary of Washington County. Services include: Innovative wastewater and stormwater services Operates 4 WWTFs Municipal separate storm sewer program (MS4) River flow management Water quality and stream enhancement projects More

4 Why a Natural Treatment System at CWS? Previously, dry season flows at the Forest Grove and Hillsboro WWTFs had to be transferred to the Rock Creek facility for treatment Significant population growth anticipated FOREST GROVE FACILITY HILLSBORO FACILITY ROCK CREEK FACILITY DURHAM FACILITY

5 Water Quality Drivers in the Tualatin River Phosphorus (FG WWTF) Ammonia (Fernhill NTS) Temperature (Fernhill NTS)

6 Fernhill Natural Treatment System Forest Grove WWTF Vertical Flow Wetlands: Ammonia Reduction Lower Treatment Wetland: Demonstration South Wetlands: Temperature Reduction Tualatin River: Outfall Upper Wetlands: TBD

7 Why a Vertical Flow Wetland? Purpose: ammonia reduction Higher oxygen transfer efficiency Ability to operate in different operational flow modes Kadlec and Wallace, 2008

8 VFW Ammonia Sorption and Nitrification NH 4 + Physical Sorption Media NH 4 + NH 4 + NH 4 + NH 4+ adsorbs onto rock surface

9 VFW Ammonia Sorption and Nitrification O 2 NH 4 + Nitrification Biofilm Media O 2 NH 4 + NO 3 - NH 4+ is oxidized to NO 2- and then to NO 3 - NO 3 -

10 VFW Pilot Study Two types of rock media Nitrification efficiency Contaminant removal Biofouling Flow modes Hydraulic loading rates (1, 2, 4, 8, 16 m/d) Flood and Drain Mode Continuous Flow Mode Rapid drainage via airlift pump

11 VFW Pilot Study Results High rates of nitrification (< 1 mg/l in effluent) High percent removal of ammonia at HLRs 8 m/d (> 80% removal) Type of media and flow mode did not make a difference

12 Full Scale VFW Design 18 MGD build-out capacity 1.3 acres 12 cells 25,000 tons of media 6 feet deep Designed for both flow modes

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14 Full Scale VFW Design Media specifications Gradation Ammonia adsorption Cleanliness

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16 VFW in Operation

17 VFW Performance

18 VFW: Volunteer Vegetation

19 South Wetlands: Surface Flow Purpose: temperature reduction 90 acres; design HRT of 4-5 days at 5 MGD Designed for passive flow Open to public

20 South Wetlands Construction 250,000 CY of soil 180 vertical snags/sill logs 750,000 plants 3.2 billion seeds 15 water control structures Construction began in 2014

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27 Achieving Plant Species Diversity

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32 2017 Plant Survey Data

33 South Wetlands: Monitoring Vegetation: diversity, percent cover, etc. Macroinvertebrates Water quality: temperature, nutrients, DO, ph, CECs, metals Birds: Audubon, bat surveys Diversity of wildlife

34 Temperature and DO Monitoring Permit requirements for temperature and DO are to be met at the NTS outfall Conducting testing under an agreement with DEQ Beginning/end/middle of cells Study cooling effects of vegetation Identify areas of concern NTS outlet (online sensors) Temperature Determine compliance Inform operational decisions DO

35 Temperature Reduction

36 Competing Interests: Low Temperatures, High Dissolved Oxygen

37 Additional Water Quality Benefits Nutrients Heavy metals Copper: complexation, uptake, ph levels Algal seeding BABs, not HABs

38 Nutrient Reduction in the South Wetlands Ammonia

39 Nutrient Reduction in the South Wetlands Total Phosphorus

40 Fernhill NTS Addresses the Triple Bottom Line

41 Economic Benefits Rock Creek Full Liquids Treatment Train = $31M* Fernhill NTS Tertiary Treatment = $18M * 2010 Dollars

42 Environmental Benefits

43 Community Benefits Birdwatching and hiking 1,085 students studying water quality, native plants, wildlife & natural treatment systems Elementary STEM partnership with sitespecific teacher training for ~20 teachers 40+ volunteer stewards Bilingual guided walks

44 PARTNERS City of Forest Grove Fernhill Wetlands Council Pacific University Public/Private K-12 Forest Grove/Cornelius Chamber of Commerce/WCVA Local Businesses (McMenamins, Maggie s, BJ s) Kiwanis/Rotary Intertwine, Audubon, Metro. Etc. Citizen Participation Organization 15

45 SUPPORT Biohabitats Kennedy-Jenks CH2M Kurisu International PLACE Studios Cascade Environmental Group ABR Inc. Waterways Consulting Ash Creek Forest Management Cole Ecological CWS Field Ops

46 Challenges NTS doesn t fit current regulatory structure Current NPDES permitting structure doesn t make it easy to permit an NTS Need to look at how to accommodate these sorts of systems Significant benefits can be overlooked Focusing on peak temperatures misses a large portion of the story

47 Next Steps Continued testing and optimization Full compliance in 2019 Denitrification/copper removal unit

48 Photo by Gary Witt Photo by Gary Witt Photo by Dale Peterson

49 Why Should it Matter to You? Contact Information: Leila Good Barker question. Regulatory Affairs Department Clean Water Services (503) Questions? Jamie Hughes Regulatory Affairs Department Clean Water Services (503)

50 Why Should it Matter to You? Good question. Extra Slides

51 Tualatin River Watershed

52 What is a Treatment Wetland? Wetland: land that is wet part or all of the year Engineered or Constructed wetlands Uses natural wetland processes for the treatment of municipal, industrial and agricultural wastewater or stormwater Stand-alone systems or add-ons to conventional secondary plants or lagoons Benefits: Low energy requirements Easy to operate and maintain Aesthetically pleasing Limitations: Large area required Inherent variability in natural systems Regulatory requirements

53 Treatment Wetland Functions Water quality treatment Temperature reduction Nutrient removal BOD removal TSS removal Others (pathogens, metals, trace organics) Water storage Habitat for plants, fish, birds, wildlife Education Complex! Treatment depends on: Inputs: Loading rates Climate (temperature, wind) Soil and plant type Operational strategies Removal Mechanisms: Sedimentation Filtration Precipitation Volatilization Adsorption Plant uptake Microbial processes

54 Fernhill NTS Treatment Wetlands Goals of NTS: Temperature Reduction Ammonia Removal South Wetlands Upper Wetlands West Wetlands Kadlec and Wallace, 2008

55 Vertical Flow Wetlands Gravel or soil beds planted with wetland vegetation Continuous vs. intermittent (pulse) dosing Continuous vs. fill-and-drain (tidal flow) operation Provides higher levels of oxygen transfer Kadlec and Wallace, 2008

56 VFW Ammonia Sorption and Nitrification Bulk Liquid Liquid Layer Biofilm Wetland Filter Media (Rock) NH 4+ adsorbs to rocks during dosing NH 4+ is released from rocks during the rest phase O 2 O 2 NH 4 + NH 4 + Dosing Draining

57 VFW Pilot Study Media Selection Utelite Stalite Bend Cinder McMinnville Steel Slag Knife River Crushed Knife River Round Waldport Crushed Marine Basalt

58 VFW Pilot Study Tested two types of lightweight aggregate filter media Nitrification efficiency Contaminant removal Biofouling Hydraulic loading modes ( Flood and Drain and Continuous ) Hydraulic loading rates Knife River Round River Rock Waldport Angular Crushed Marine Basalt

59 1 Upper Constant Siphon Lower-level Mid-level Wetland Grow Columns Boxes Head Lights Plants Totes 3 Tank 13 &

60 Ammonium Exchange Capacity Test 43 g NH 4+ /m 3 62 g NH 4+ /m 3 Knife River Round River Rock Local Source Highest AEC Waldport Angular Crushed Marine Basalt

61 VFW Column Layout 1 2 Top Dressing - Superfines 3a 3b Top Dressing - Fines Knife River Round Treatment Media Waldport Crushed Basalt Treatment Media Drainage River Rock Drainage Cobble

62 VFW Pilot Study Results Knife River Waldport 8 m/d 1 m/d 4 m/d 2 m/d 16 m/d Target NH 3

63 Average Ammonia Removal Performance Flood-and-Drain Flow Vertical-Flow HLR (m/d) Media Type Influent Effluent % Removal Influent Effluent % Removal Waldport 16.9 ± ± ± ± Knife River 13.7 ± ± ± ± Waldport 23.7 ± ± ± ± Knife River 25.5 ± ± ± ± Waldport 23.1 ± ± ± ± Knife River 24.3 ± ± ± ± Waldport 20.2 ± ± ± ± Knife River 19.4 ± ± ± ± Waldport 19.4 ± ± ± ± Knife River 18.2 ± ± ± ± Target Effluent NH 3 -N Concentration was < 1mg NH 3 -N/L Average NH 3 -N Concentration (mg/l)

64 Vertical Flow Wetlands Design Guidelines 8 m/d HLR, 6 ft depth, ft 2 *Design Flowrate: 6 MGD

65 Full Scale VFW Design

66 Full Scale VFW Design

67 Other Examples of VFWs Tidal Vertical Flow Wetland, Israel Continuous Vertical Flow Wetland, China

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70 Fernhill Data Points Map

71 Effect of gate closure Automatic closure Trigger: 24 C Avoid discharging water warmer than 25 C

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73 5. Thermal stratification in the Pond

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76 Nutrient data

77 Species Dominance and Frequency

78 Areas of Sparser Vegetation