Rain Gardens Landscaping for water quality Presented by the Soil and Water Conservation District of Lake County

What is a rain garden? A rain garden is a shallow depression in your yard that is planted with native flowers and grasses A rain garden is a shallow depression in your yard that is planted with native flowers and grasses It is positioned in the yard to receive runoff from your roof, sidewalks, driveway and lawns allowing water to slowly soak into the ground It is positioned in the yard to receive runoff from your roof, sidewalks, driveway and lawns allowing water to slowly soak into the ground

Rain gardens – a short history Rain gardens are a relatively new concept Rain gardens are a relatively new concept They emerged in 1993 in Maryland out of the need for low cost stormwater infiltration methods that would improve water quality They emerged in 1993 in Maryland out of the need for low cost stormwater infiltration methods that would improve water quality The idea of bioretention or holding and filtering stormwater in plant systems came about The idea of bioretention or holding and filtering stormwater in plant systems came about The term was later refined as rain gardens as it was more attractive The term was later refined as rain gardens as it was more attractive Since then, the concept of rain gardens has been developed by other states especially Minnesota, Michigan and Wisconsin Since then, the concept of rain gardens has been developed by other states especially Minnesota, Michigan and Wisconsin A more widespread use of such gardens could dramatically improve water quality everywhere A more widespread use of such gardens could dramatically improve water quality everywhere

Why are they important? The conversion of land from forests, grassland and agricultural land to urban and suburban lots has reduced the natural ability rain water to infiltrate into the ground because of increased impervious surfaces The conversion of land from forests, grassland and agricultural land to urban and suburban lots has reduced the natural ability rain water to infiltrate into the ground because of increased impervious surfaces This results in stormwater runoff that carries pollutants from streets, parking lots and lawns into our local lakes and streams, degrading their water quality This results in stormwater runoff that carries pollutants from streets, parking lots and lawns into our local lakes and streams, degrading their water quality

Why are they important?  Chicago ( )…  288,000 acres converted 35% increase in developed land 35% increase in developed land 4 % increase in population 4 % increase in population Urban areas are spreading rapidly... Green Infrastructure: A Strategic Approach to Natural Resource Planning and Conservation

Why are they important? One way we can improve water quality right on our own properties, is by planting rain gardens, that can filter and re-direct rain water One way we can improve water quality right on our own properties, is by planting rain gardens, that can filter and re-direct rain water Even though they are small in size, collectively they can make a big difference Even though they are small in size, collectively they can make a big difference

Rain Garden Basics Location Location Your rain garden should be at least 10 feet away from your house Your rain garden should be at least 10 feet away from your house It can be placed close to your downspout so it only receives water from the roof It can be placed close to your downspout so it only receives water from the roof Or further away so it catches water from your roof and your lawn Or further away so it catches water from your roof and your lawn Don’t put it where water already ponds – the idea is to encourage infiltration Don’t put it where water already ponds – the idea is to encourage infiltration Plants will grow easier in full sun than in shade or under a tree Plants will grow easier in full sun than in shade or under a tree A flat area of the yard will be easier to dig than on a slope A flat area of the yard will be easier to dig than on a slope

Location Picture courtesy of Wisconsin DNR

Location

Rain Garden Basics Size Size You should choose a garden size that you can manage; typical sizes are between 100 and 300 sq.ft. You should choose a garden size that you can manage; typical sizes are between 100 and 300 sq.ft. The depth can vary between 4 and 8 inches The depth can vary between 4 and 8 inches A garden that is too small and too shallow will not have enough plant variety and will not provide appropriate infiltration A garden that is too small and too shallow will not have enough plant variety and will not provide appropriate infiltration Similarly a garden that is too large and too deep will be hard to maintain, expensive and will resemble a hole in the ground filled with water Similarly a garden that is too large and too deep will be hard to maintain, expensive and will resemble a hole in the ground filled with water

Rain Garden Basics Size Size To find the perfect size for your garden take into considerations a few things: To find the perfect size for your garden take into considerations a few things: Soil types Soil types Drainage area that will feed into the garden Drainage area that will feed into the garden Depth of garden Depth of garden Clayey soils drain slower that sandy and silty Clayey soils drain slower that sandy and silty The bigger the drain area, the bigger the garden should be The bigger the drain area, the bigger the garden should be Depth of garden should be determined by the slope of the lawn Depth of garden should be determined by the slope of the lawn

Rain Garden Basics Determine soil type Determine soil type The soaking test The soaking test The ribbon test The ribbon test Determine the drainage area of your property Determine the drainage area of your property For gardens less than 30 feet from downspout For gardens less than 30 feet from downspout For gardens more than 30 feet from downspout For gardens more than 30 feet from downspout Determine the depth of the rain garden by determining the slope of the lawn Determine the depth of the rain garden by determining the slope of the lawn

Determining slope Picture courtesy of Wisconsin DNR

Rain Garden Size Having determined soil types, drainage area and depth, you can now calculate the surface area of your garden Having determined soil types, drainage area and depth, you can now calculate the surface area of your garden Use the table below to do that Use the table below to do that 1.Find the size factor for the soil type and rain garden depth. 2.Multiply the size factor by the drainage area. This number is the recommended rain garden area. 3.If the recommended rain garden area is much more than 300 square feet, divide it into smaller rain gardens.

Building Your Garden Anytime before digging in your garden you should call JULIE (Joint Utility Locating Information for Excavators) at Anytime before digging in your garden you should call JULIE (Joint Utility Locating Information for Excavators) at Recruit some friends to help you out so the work will take less time Recruit some friends to help you out so the work will take less time Do some advanced prep work to lighten up the physical load Do some advanced prep work to lighten up the physical load

Building Your Garden Start out by defining the shape of the garden with a string or a flexible hose Start out by defining the shape of the garden with a string or a flexible hose While you dig put the soil outside of the string; you will use the displaced soil to build a berm or a low wall While you dig put the soil outside of the string; you will use the displaced soil to build a berm or a low wall If you are on an incline start out at the high end and work your way towards the low end; make sure you know how deep your garden has to be If you are on an incline start out at the high end and work your way towards the low end; make sure you know how deep your garden has to be When you are done digging check to see that the bottom of your garden is flat; you can “eyeball it” or use a 2x4 and a carpenter’s level When you are done digging check to see that the bottom of your garden is flat; you can “eyeball it” or use a 2x4 and a carpenter’s level

Picture courtesy of Wisconsin DNR Building Your Garden

Picture courtesy of Wisconsin DNR

Building Your Garden If your lawn has a slope greater then 8% you will need to use some of the soil you dig to level the garden If your lawn has a slope greater then 8% you will need to use some of the soil you dig to level the garden The rest of the soil will be used to build the berm The rest of the soil will be used to build the berm When you are done digging, rake the soil smooth and prepare for planting When you are done digging, rake the soil smooth and prepare for planting For better plant establishment compost can be used; you can mix it with your soil For better plant establishment compost can be used; you can mix it with your soil

Building Your Garden Picture courtesy of Wisconsin DNR

Choosing plants You should choose plants based on the sun/shade pattern and soil type to ensure proper growth You should choose plants based on the sun/shade pattern and soil type to ensure proper growth Native plants is they way to go due to their resilience and low maintenance needs Native plants is they way to go due to their resilience and low maintenance needs They come in different varieties and colors, they are drought resistant and they don’t require fertilizer and pesticides They come in different varieties and colors, they are drought resistant and they don’t require fertilizer and pesticides

Picture Courtesy of Chicago Wilderness Root system of the prairie grasses

Plants for full sun

Plants for partial shade

Plants for shady areas

Planting You should come up with a pleasing design keeping in mind the height of the plants and color variation You should come up with a pleasing design keeping in mind the height of the plants and color variation Clump plants together for a visually enjoying display Clump plants together for a visually enjoying display Do not exclude the rest of your property – plan the rain garden as part of a whole Do not exclude the rest of your property – plan the rain garden as part of a whole Native plants should be planted about 1 foot apart to allow roots to grow well Native plants should be planted about 1 foot apart to allow roots to grow well As soon as you finish mulch and water As soon as you finish mulch and water

Maintenance The first year after planting your rain garden is very important in terms of maintenance The first year after planting your rain garden is very important in terms of maintenance It will determine how well your garden will do in the future It will determine how well your garden will do in the future Two key components are watering and weeding Two key components are watering and weeding Second component cannot be emphasized enough since the plants and weeds are in powerful competition for resources Second component cannot be emphasized enough since the plants and weeds are in powerful competition for resources Once the garden is established (typically it takes 2-3 years for complete establishment) the amount of maintenance will reduce considerably Once the garden is established (typically it takes 2-3 years for complete establishment) the amount of maintenance will reduce considerably

Alternative to Rain Gardens If you feel that installing a rain garden is too much work, you can take advantage of rain barrels If you feel that installing a rain garden is too much work, you can take advantage of rain barrels They collect rain water from your roofs, which can be used for irrigation later They collect rain water from your roofs, which can be used for irrigation later It is a cheap, easy alternative and requires no maintenance It is a cheap, easy alternative and requires no maintenance

Rain Barrels Residential irrigation can account for 40% of domestic water consumption in a given municipality Residential irrigation can account for 40% of domestic water consumption in a given municipality Rain barrels not only store water, they help decrease demand during the times when precipitation is scarce Rain barrels not only store water, they help decrease demand during the times when precipitation is scarce Only 1/4 inch of rainfall runoff from the average roof will completely fill the typical barrel Only 1/4 inch of rainfall runoff from the average roof will completely fill the typical barrel

Rain Barrels Rain water is ideal for watering your gardens because it tends to have fewer sediments and dissolved salts than municipal water Rain water is ideal for watering your gardens because it tends to have fewer sediments and dissolved salts than municipal water Saving water in this manner will reduce your demand for treated tap water, and save money by lowering your monthly bill Saving water in this manner will reduce your demand for treated tap water, and save money by lowering your monthly bill

Rain Barrels Picture Courtesy of

Resources One of the best resources is the booklet I used for this presentation “Rain Gardens – A How To Manual For Homeowners One of the best resources is the booklet I used for this presentation “Rain Gardens – A How To Manual For Homeowners The Soil and Water Conservation District of Lake County can help answering any questions about native plants The Soil and Water Conservation District of Lake County can help answering any questions about native plants Also Applied Ecological Services can help with designs and planting ideas Also Applied Ecological Services can help with designs and planting ideas

Rain gardens

Questions ???