Amy Bouska Urban Conservationist IDALS-Division of Soil Conservation

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1 Amy Bouska Urban Conservationist IDALS-Division of Soil Conservation

2 Wayne Petersen Wallace Building, Des Moines Derek Namanny Spirit Lake FO x 3 Derek.namanny@ia.nacdnet.net Jennifer Welch Ankeny FO x 3 Jennifer.welch@ia.nacdnet.net Amy Bouska, Iowa City FO x 3 Amy.bouska@ia.nacdnet.net

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4 Controlling erosion and sediment on construction sites Urban stream corridor stabilization Utilizing better site design principles Reduce amount of stormwater runoff and improve the quality of water in urban areas

5 Utilize many small scale practices throughout a drainage area lot level management of runoff, rather than end of pipe/end of drainage area management. Mitigate impacts of adding impervious surfaces reduce higher volumes of runoff, reduce degradation of water quality, reduce flashiness of stream flows. Restore ground water recharge. Utilize a watershed approach

6 Appanoose Black Hawk Buchanan Cedar Clinton Des Moines Jackson Jefferson Johnson Jones Linn Poweshiek Scott Washington

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10 Water Quality Volume (WQv) (1.25 inch/24 hrs) Channel Protection Volume(CPv) (2.4 in/24 hrs) Overbank Flood Protection (Q p ) (4 inch/24 hrs) Extreme Flood Protection (Q f ) (6 inch/24 hrs)

11 The first flush of rainfall moves pollutant loads to surface waters Use practices that retain water from the small storms water on-site Strategies include: soil quality enhancement reducing soil compaction vegetation selection 75% of storms <0.5 inch 90% of storms < 1 inch

12 Q p after development Q Result: Big peaks reduced for flood control, creating extended duration of elevated flow over a longer period of time damage Time Q with conventional detention

13 Properties threatened by stream erosion in Des Moines

14 Retain rain on site. 10% 50% Mimic the hydrology of the native ecosystems. Infiltrate more. Shed less.

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18 Sedums growing at Roof Top Sedums in Davenport, IA

19 (60%-70% of imperviousness)

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21 De-compaction Apply compost to increase OM content Strive for Five (5% OM content minimum)

22 Prairie soils had 8-10% organic matter content and 45% pore space Now soils have < 4% OM Even less organic matter on construction sites Bulk density has increased less pore space Soils have lost 60-80% of their ability to absorb and infiltrate rainfall events

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24 0.6 of rain is absorbed per % of OM (6 absorbed on the prairie without shedding runoff) 19,000 gallons of runoff per % of OM Most upland soils will store 0.15 to 0.2 inches of water per inch of soil profile A healthy 3-foot soil profile has the potential capacity to store 5.4 to 7.2 inches of rain (110 year storm) At 2% OM runoff can begin after 1.25 inches of rain

25 Deep tillage reduces concretelike compaction in urban settings

26 Existing turf areas Turf grass after application of compost Aerate soils prior to compost application

27 Engineers for a Sustainable World University of Iowa

28 Rain garden at Forever Green Landscape and Nursery in Coralville

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30 WATER VOLUME WATER DEPTH

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33 Most watersheds include both agricultural and urban lands.

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35 IDALS funds Urban Conservationist REAP cost-share-~$7,000 3 local municipalities offer own funding to homeowners, businesses, and nonprofits Stormwater loan-srf Sponsored projects-srf County Funded position

36 The Department has years of experience working with farmers and believes this is just the beginning of efforts to assist urban areas. Urban Conservationists will help communities install new systems and retrofit existing infrastructure in a way that will move the water off our streets while keeping soil and pollutants out of our waterways. Our goal is to have urban and rural areas working together to protect our soil and improve water quality in the state. Secretary of Agriculture Bill Northey

37 Agriculture County Urban District

38 Provide technical assistance to private landowners to implement conservation systems on their property Conservation Planning Watershed Planning Survey & Design Financial Assistance Partner or work closely with other government agencies

39 Provide technical assistance to consultants, engineers, developers on subdivision and commercial site plans Review & Approve Sensitive Area Plans Wetlands, threatened & endangered species, savanna s, prairie remnants, cultural resources, unstable landforms, etc Review & Approve Sediment & Erosion Control Plans Certified Inspector of Sediment & Erosion Control (CISEC) Review & Approve Stormwater Site Plans GIS Sensitive Area Database County Property Stormwater Assessment

40 District Urban Education & Outreach Booths Presentations Field Days Website/Facebook Grant Writing & Administration Volunteer Coordinator Earth Team Volunteer Provide education & technical assistance to landowners, consultants, engineers, developers and public agencies Promote Rainscaping Iowa Practices

41 Kate Giannini Soil & Water Conservation Specialist Johnson County Planning & Zoning & Johnson Co. SWCD ext.3 Find us on Facebook!