How to Maintain Your Rain Garden, Bioswale, & Micro-Bioretention Practices

WHAT ARE RAIN GARDENS, BIOSWALES, AND MICRO-BIORETENTION PRACTICES? Rain gardens, bioswales, and micro-bioretentions are best management practices (BMPs) for stormwater management that double as functional landscaping features. These stormwater practices filter stormwater runoff and improve water quality.

Micro-bioretention practices are typically planted with native plants and have three layers: mulch, a layer of soil, sand, and organic material mixture; and a stone layer. A perforated pipe is often installed within the stone layer to good to do... collect and direct the filtered rainwater from large storms to a storm drain system so the micro-bioretention drains Monthly within four days. Micro-bioretention practices are often R Regularly inspect the practice for signs of erosion, located in parking lot islands, cul-de-sac islands, residential obstructions, or unhealthy vegetation. lots, or along roads. R Remove weeds and invasive plants. R Remove any trash that has washed into the Rain gardens are very similar to micro-bioretention, except bioretention area or the inlet channels or pipes. they do not typically have a buried perforated pipe. These R Check the facility a few days after a rain storm to make practices retain water and encourage rainwater to infiltrate sure that there is no standing water after 4 days. instead of running off into storm drains. They often collect water from roof gutters, driveways, and sidewalks. Rain As Needed gardens are common around residential lots. R Cut back dead stems of herbaceous plants in March and remove from the facility. A bioswale is similar to a micro-bioretention practice in R Water new plants during initial establishment of the way it is designed with layers of vegetation, soil and a plant growth (first 18 months) and extreme droughts. perforated pipe within the bottom stone layer. Bioswales Watering should only be needed when it has not typically are located along a roadway. rained for more than 10 days. R Replenish and redistribute mulch to a total depth of 3 These stormwater BMPs need regular maintenance, similar inches at least every 3 years. to other landscaped areas, including: weeding, removing R If you observe severe erosion, reestablish grass and trash and debris, pruning, and mulching. vegetation. For guidance, contact your locality. R In all, remove fallen leaves from the area. Leaves may WHY ARE MICRO-BIORETENTION PRACTICES block the flow of rainwater. IMPORTANT? Micro-bioretention practices improve the health of local waterways by removing pollutants and sediment from Don't... stormwater runoff. Q Apply excess salt and sand around the property in winter. Why is it important to maintain these practices? Q Store snow and leaves on top of the bioretention area. Unmaintained rain gardens, bioswales, and micro- Q Use fertilizer or pesticide. bioretention practices may: • Stop filtering the rainwater and allow pollutants to enter our local waterways. • Be difficult or expensive to restore if left unmaintained. • Allow water to pool on the surface long enough to You can prolong the life of your rain garden, allow insects to breed (longer than three days). bioswale, and micro-bioretention facility and save on maintenance costs by keeping your site clean and By maintaining these practices, you are doing your part regularly inspecting and maintaining the facility to to help protect your local streams and the Chesapeake ensure it is functioning properly. Bay. Accordingly, maintaining them may be required by your municipality or your local VSMP (Virginia Stormwater Management Program) Authority. AREAS ING, REPAIRING ERODED WATERING, REPLANT MULCHING PRUNING WEEDING REMOVE TRASH & DEBRIS REMOVE SEDIMENT, LEAVES Content presented ofEnvironmental inthisfactsheet was Protection,County, originally developed Montgomery by the Department MD. making any changestomaking your rain garden, bioswale or or visitusonlineat assistance, pleaseemailusat [email protected], call(757)420-8300, you with the stormwater in connecting professionals in your locality. For No matter where you are inHampton Roads, askHRgreen.org canassist and provide additionalguidance aboutmaintaining your stormwater facility. Your orlocal municipality StormwaterVSMP (Virginia Program) Management cananswer Authority your questions WHAT IF I NEED HELP OR HAVE ADDITIONAL QUESTIONS? If yourIf stormwater BMPwas installedasacondition contact your tocontact discussoptionsbefore municipality

TROUBLESHOOTING of development, itcannotberemoved. isbestto It Erosion orbare soil Standing water SYMPTOM reduced mulch No mulchorvisibly facility Weeds taking over Dead ordyingplants CAN I REMOVE THE PRACTICE? micro-bioretention practice. - askHRgreen.org/WaterQuality RECOMMENDED TIMEFRAMES FOR TYPICAL MAINTENANCE Large storms can alsomove mulch. Mulch naturally decomposes over time. seeded may take multiple years to kill. Established weeds that have already they may besmothered by weeds. for your shadeandmoisture conditions, or Your plants may bethewrong plant type vegetation hasdied. The runoffismoving too fast and/or the rain may beblocked. the facility could ortheunderd beclogged If standing water occurs for over 4days, POSSIBLE CAUSE JAN R R FEB R R R MAR R R R . APR R R R MAY R R R AS NEEDED JUN R R - see them.Donotallow weeds to go to Manually remove weeds assoonyou Plant new vegetation. If needed,userocks to slow theflow. Stabilize thesoilby planting new vegetation. cleaned. replanted, orthepipemay needto be The facility may needto betilledand SOLUTION inches over theentire facility. Replenish mulchto a total depth ofthree mulch. seed. Usegood qualitydoubleshredded JUL R R AUG R R R SEP R R R OCT R R R NOV R R R R R DEC R