The appropriate plants should be placed throughout the bioswale to remediate introduced stormwater , prevent erosion , attenuate volumetric flow of stormwater , and provide aesthetic appeal . Additional compost can be added to planting sites to help retain moisture and provide a gradual source of nutrients as plantings become established . Native plants are highly recommended to be placed in bioswales due to their suitability in the local environment . Natives also produce deeper root systems , which hold onto the soil to prevent erosion and increase the uptake of water from soils in bioswales . The section on rain gardens provides a general list of plants to consider for bioswales .
Maintenance and Monitoring
ENHANCED BIOSWALES
During the first year , irrigation should be installed in order to allow the transplanted vegetation to establish . The first few years while the plants are being established , the bioswale will need to be weeded occasionally . After plants establish and begin to fill in the area , the frequency of weeding is expected to be reduced in subsequent years . Irrigation should be gradually reduced over the establishment year and eventually turned off , only to be used in the future during periods of drought .
Over the growing season , overgrowth should be removed as necessary to maintain the aesthetic appearance of the bioswale . Additionally , periodic vegetative maintenance , clearing of debris and sediment removal will be required . If the area incorporates the use of St . Augustine grasses , it is recommended that the grass not be cut shorter than the design flow depth in the bioswale . At the end of the growing season , dead plant material can be removed to promote healthy plant growth in the following season . Overall , maintenance varies by site and vegetative composition . Installed pipes should be checked every four to five years to note any issues with clogging or poor drainage .
In addition to maintenance , monitoring of the bioretention area ’ s efficacy is encouraged . Routine inspections for signs of erosion , blockages , or evidence of ponding water are encouraged by Charleston County .
FALL 2022
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