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Espsom salts #749538
Asked May 12, 2021, 4:20 PM EDT
Benton County Oregon
Expert Response
Greetings,
Reusing bathwater for plants would seem like a sensible water conserving solution. However there are a few issues:
According to OSU's well water program, "In Oregon, it is currently illegal to use untreated gray water.... Currently, in Oregon, gray water is classified as sewage and is regulated under OAR 340-071 (Oregon's onsite wastewater treatment system regulations). Treatment and reuse of gray water requires appropriate DEQ permits.
To treat and use gray water requires a permit which, in most cases, is prohibitively expensive. The Oregon Department of Environmental Quality is in the preliminary stages of considering changes to gray water regulations.
DEQ's graywater fact sheet covers background, basic graywater information, and permitting questions....Future changes may result in greater flexibility for homeowners to reuse gray water while protecting the health of the community. Keep checking to see if DEQ makes any further changes to graywater use regulations."
Under circumstances where greywater use in home gardens is legal, you would most likely not want to use water with large amounts of Epsom salts unless your soil is low in magnesium. According to University of Minnesota Extension,
- "Adding Epsom salts to soil that already has sufficient magnesium can actually harm your soil and plants, such as by inhibiting calcium uptake.
- Spraying Epsom salt solutions on plant leaves can cause leaf scorch.
- Excess magnesium can increase mineral contamination in water that percolates through soil."
Here's a thought for simple water conservation that bypasses these issues: when running water to warm it up for a bath or shower, catch it in a bucket and use that bucket to water some plants. You could keep a bunch of houseplants watered this way and save several gallons that would otherwise be wasted every time you bathe.
On May 12, 2021, at 1:53 PM, Ask Extension <<personal data hidden>> wrote: