Pesticide Users

Adopting preventative practices and measures on your property is a critical first step in mitigating contaminant release.

The following list provides several positive actions you can take when using pesticides to avoid potential groundwater contamination.

Identify pests, determine pest population size and affected areas. Then, make pesticide applications only as necessary, using the lowest rate necessary for adequate pest control. DO NOT OVER APPLY! Carefully calculate, according to the label rate, the quantity of pesticide concentrate required to treat the specific area. Using more product than the recommended dose is a waste of product, money, and can lead to unnecessary pollution. It does not kill more pests! Pesticides, when applied infrequently and in low concentrations, are less likely to leach into groundwater. In addition, careful calculations of required quantities will eliminate disposal problems associated with excess pesticide solution.

Carefully time applications to reduce the need for frequent applications and to prevent unnecessary pollution. For example, delay the application of pesticides if heavy or sustained rainfall is anticipated. Heavy rainfall or irrigation on freshly applied pesticide can cause the pesticide to wash off and find its way into the groundwater system by percolating down through the soil or by flowing with surface runoff into streams and rivers, which recharge the aquifer. 

Select pesticides that are less likely to leach into groundwater and surface waters. Highly soluble pesticides that do not adsorb to soil particles are most likely to leach into the ground and impact groundwater quality. Prior to selecting pesticides, inspect product labels for restrictions related to application rate and timing or advisories and water protection guidelines. Pesticide dealers or the Pesticide Regulatory Agency may be able to assist you further in selecting an appropriate pesticide.

Consider the location of pesticide application in relation to groundwater and surface waters. If the proposed treatment area lies within the boundaries of the highly vulnerable groundwater area (as indicated by the red areas of the map), then abandon pesticide use or seek an alternative treatment that does not involve a hazardous pesticide. Recall that in the red areas of the map, the groundwater table lies only a shallow two to five meters below the highly permeable soil at the surface and is therefore very susceptible to surface contaminants such as pesticides. Avoid applying pesticides near other groundwater-sensitive areas such as springs, streams, ponds, wetlands, wells, drains, and sinkholes. 

Calibrate pesticide distribution equipment carefully prior to use, to ensure that the appropriate quantity of pesticide is applied. Check equipment for leaks and malfunctions to prevent spills that may lead to contamination. 

Handle pesticides carefully to avoid spills. Whenever possible, mix and load pesticides on a concrete surface. This will avoid saturating the soil with spilled pesticide and allows any spills or overflows to be captured for cleaned up. In addition,

  • Fill the spray tank as far from wells or water sources as possible (minimum 30 metres). Use a long hose or an alternate water source, such as a nurse tank, while in the field.
  • Keep the end of the fill hose above the water level in the spray tank. This will prevent back siphoning of the pesticide into your water supply. Anti-back flow devices, such as check-valves, are an option.
  • Fill spray tank to no more than 90 to 95 percent of its capacity. This will help avoid splashing of the pesticide solution out of the container while it is transported.
  • Never leave the spray unit unattended when filling.

Minimize your pesticide inventory by purchasing only the type and quantity of pesticide required for the season or a specific application. The storage area should be away from all water sources. A concrete floor sealed with an impervious material facilitates clean up in the event of a spill or leak. Inspect containers regularly for leaks and corrosion. Bulk pesticide storage tanks should be inspected frequently and placed on concrete pads with dikes built around them to prevent the movement of pesticide should a spill or leak occur. 

Best Management Practices for Insecticide Use

Rather than resorting to another chemical product, why not try an alternative to insecticides, nature’s own beneficial bugs?  Insects that consume other insects (the ones often responsible for damaging plants within your garden) are called “beneficial bugs”. Examples of beneficial bugs include flies, dragonflies, beetles, ladybugs, lacewings, and spiders. Some suggestions on how you can incorporate beneficial bugs into your gardening or lawn care practices are given below.

Avoid using broad-spectrum insecticides or residual chemicals, as these kill beneficial bugs as well as pests

Plant pollen and nectar plants to attract beneficial bugs. Examples of attracting plant species include daisies, coneflowers, yarrow, alyssum, candytuft, marigolds, phacelia, salvias and schizanthus. Several plants typically deemed as weeds are actually excellent for attracting beneficial bugs. Beneficial “weeds” include dandelions, goldenrod, wild carrot, lamb’s quarters, nettles, and wild mustard. 

Create a water source containing large rocks, which will serve as a perch, to attract beneficial bugs such as dragonflies. 

If you must use an insecticide, choose a product that breaks down easily in the environment, such as insecticides containing pyrethrins as the active ingredient or insecticidal soaps. For further information contact the Pest Management Regulatory Agency. 

Facts from BC Environment, 1992, Beneficial Insects, Safe and Sensible Pest Control.

For Further Information

Drinking Water in the City of Chilliwack
        Engineering Department
        City of Chilliwack
        8550 Young Road
        Chilliwack, BC
        (604) 793-2907

Recycling Hazardous Materials
        Recycling Hotline

        Chilliwack Bottle Depot
        45934 Trethewey Avenue
        (604) 792-9572

Groundwater Protection
      BC Ministry of Environment 
       2nd floor, 10470 - 152nd street
        Surrey, BC
        (604) 582-5200

Pest Management Regulatory Agency
       Suite 400 -  4595 Canada Way, Burnaby, BC
        (604) 666-0741