WATER ISSUES
By Julie Newman
Manage Runoff With
Vegetated buffers prevent pollutants from ending up
in surface and groundwater.
Vegetated Buffers
Growers must implement prac- tices to protect water resources and comply with increasing
regulations. Installation of vegetated
buffers is one method that can be used
to prevent pollutants, such as fertilizers,
pesticides and container media, from
ending up in surface and groundwater.
or swamp for treating wastewater, controlling flood waters and reducing erosion. Wetlands can be built to further
remove pollutants in the effluent from
a retention basin.
How vegetated buffers work
Although there are different types of
vegetated buffer systems, most work
in a similar manner. Runoff containing
soluble nutrients, pesticides and sedi-
ments with adsorbed pesticides, enters
the buffer. Vegetation in the buffer
slows surface flow and sediments drop
out. Some water infiltrates into the root
zone and subsoil, while the remainder
becomes lateral subsurface flow.
Buffer benefits
Vegetated buffers are areas or strips
of land maintained in permanent vegetation to prevent erosion and improve
water quality by trapping and treating
contaminants. Vegetated buffers can
also provide other benefits, including
enhancing wildlife habitat, increasing
beneficial insects for biological control
of crop pests and protecting stream
banks. The buffers can also be used for
green waste and secondary crop production.
Types of vegetated buffers
Vegetated bioswale. A vegetated bioswale is a stormwater conveyance system that channels stormwater. This
type of buffer system improves water
quality by reducing flow velocity and
increasing sedimentation, filtering pollutants and allowing infiltration into
underlying soils.
Filter strip. A filter strip is a band of
vegetation that can be used between a
greenhouse and a water body. The purpose of the filter strip is to slow runoff
from the production area and trap sediment, fertilizers and pesticides before
they reach surface water.
Constructed wetlands. A constructed wetland is an artificial marsh
Equisetum and other plants that tolerate poor drainage and wet conditions are placed in
drainage areas to take up water and soluble nutrients and pesticides in these vegetated
bioswales. The plants are periodically harvested as a crop.
