Stormwater Retrofits Made Practical City of Eugene Oregon. Doug Singer, P.E., CSM Principal Civil Engineer City of Eugene Public Works

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1 Stormwater Retrofits Made Practical City of Eugene Oregon Doug Singer, P.E., CSM Principal Civil Engineer City of Eugene Public Works

2 Doug Singer Introduction BS Civil Engineering from Oregon State University Registered Professional Engineer in Oregon Principal Civil Engineer, Stormwater Capital Program Manager, City of Eugene Director, Oregon APWA Executive Board, APWA member since 2004 City of Eugene Oregon PW APWA Accredited Agency Population 156,000 Presentation topic: Water Quality Retrofits Why do WQ Retrofits Planters / Vegetated planters Neighborhood Swales Porous or Pervious Concrete Pavement Costs and Maintenance

3 Why do stormwater quality retrofits? Clean Water for streams and rivers Solve flooding problems /Add hydraulic capacity Reduce downstream hydromodification effects Regulation Clean Water Act NPDES Eugene MS4 Phase 1 Safe Drink Water Act Eugene has UIC s

4 Hardscape features Curbs and walls Spillways & Splash pads Planter Inlet Weirs Sidewalk grates Planter Design features Landscape features (not going to cover) Soil Mulch or no mulch Plants Trees or no trees

5 Flow into planter Trap Sediment Slow the flow Car safety Easy maintenance Spillways and splash pads

6 New spillway and splash pad Covered spillway with splash pad Open spillway with splash pad

7 Cool Spillway, Portland OR

8 Parking step out Notched curb along sidewalk Side curbs Walls and curbs

9 Nice

10 Planter Inlets pipe to storm system

11 Weir longer or multi-section planters

12 Hybrid planter / swale next to Park

13 Sidewalk grate acts as Weir

14 Cul-de-sac curved planter, no sidewalk

15 Bump out plant

16 Sidewalk bump out, triple planter

17 Benefits Neighborhood swales Single swale serves a neighborhood 30 Acres Drainage Area 1 facility to maintain Requires a large area for the swale 4,800 feet new pipe Eliminated 16 Drywells Overflow to Spring Creek and Lane County storm system Built in 2012

18 Ferndale Park Swale Image courtesy of Google Maps

19 Ferndale Park Swale Pre-Construction 2012

20 Ferndale Park Swale Big Dig September 2012

21 Ferndale Park Swale New plants November 2012

22 Ferndale Park Swale May 2015 year 3

23 Pervious Concrete Pavement Changing gutter grade and flow pattern flow into the pavement with reverse curb and gutter Drainage Area Soil infiltration rates Rock base reservoir Overflow to system Mix design Surface finish Maintenance

24 Mix design and finish are critical NO POPCORN PAVEMENT ¼ inch open gradation with sand Fiberglass fibers for strength Stabilizer adds finishing time FINISHING Roller tube finish & compaction Transverse roller compaction Weighted Fresno Mostly closed surface

25 Mix design Gradation for Pervious Concrete Aggregate ¼ inch Aggregate Void Content 40% (minimum) Sieve Size Percent Passing (By Weight) 3/ /4" 96 No No No No No No No Concrete sand 5% Portland Cement 611 lbs / cubic yard Fibermesh lbs / cubic yard Water Cement ratio 0.40 at mixing, 0.45 (maximum at placement) Target void at the surface 15 to 25% Target Flexural strength at 28 days 350 psi (minimum) Maximum 30% slag cement or 20% fly ash, Portland Cement replacement Hydration stabilizing admixture to allow two hour working time

26 Open graded aggregate 24 depth open graded aggregate base Storage reservoir

27 Placing and finishing (show video)

28 Rainy day

29 Costs Planter construction cost Typical planter $12,000 - $15,000, complicated up to $25,000 Ferndale Swale project $1-million Whole project: swale and 4,800 foot piped system Pervious Concrete Pavement: $62,000 for 2,600 square feet or $24 square foot 9 Concrete cost only $25,000 or $10 square foot Other costs in concrete area $12,000 Transition sections costs $25,000 Maintenance 13 rain gardens in in in 2017 FY 18 $470,000 maintenance budget FY 19 $570,000 maintenance budget Concrete pavement vacuum street sweeping at least twice a year more is better (no additional budget as of now)

30 Resources City of Eugene Stormwater Management Manual online City of Eugene Standard Specification and Drawings Drawings specific to planter components Thank you too: American Concrete Pavement Association (ACPA) concrete construction specification Portland Cement Associate (PCA) concrete mix design

31 Swale in Open Space / Park Vegetated Planter Thank you! Doug Singer, PE, CSM City of Eugene Public Works doug.k.singer@ci.eugene.or.us Pervious Concrete Pavement