Can I Plant Over my Drain Field / Leach Field?
The answer is yes! Planting helps mitigate any erosion of the soil over the drain field. Plants can actually help the system to function more effectively by optimizing oxygen exchange and helps promote soil moisture removal through transpiration. You may also want to plant because your drain field in in the front yard and that's the only place available to plant. But please note, planting certain types of vegetation on or near your field system could be potentially dangerous. The root system of some plants are deep rooted and could penetrate the drain field causing major problems and could possibly cause your system to back up into your house because there is a reduction in flow caused by the roots.
Type of Flowers and Shrubs That Have Shallow Roots
Flowering annuals and perennials (including bulbs) are unlikely to clog and damage drain lines. Low shrubs like heathers and miniature roses do well in shallow soil. Shallow rooted shrubs and ornamental grasses are also good.
Important Precautions to Take Before Planting
Adding to much soil to the area along with heavy mulch can affect the normal evaporation process that removes the excess moisture. The same can happen when over-watering plants. It's also good to remember that field lines can be 6 inches in the ground and deeper. So please take precaution when digging and wear gloves to protect your skin and minimize the exposure from harmful organisms.
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