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Wastewater smart!

Is your holding tank deodorizer eco-friendly?

Tip: Chemical-based tank deodorizers contain formaldehyde, metals and/or other harmful chemicals.

Unfortunately, not only do chemical-based deodorizers pollute soil and groundwater and produce toxic fumes, but they can corrode your camper's pipes and tanks. To protect Michigan's great outdoors and your health, please use (non-chemical-based) biodegradable tank deodorizers.

Be wastewater smart

Be wastewater smart!

What to do

  • Use biodegradable (enzyme- or bacterial-based) tank deodorizers only.
  • Follow deodorizer label directions and add only what is recommended.
  • Tell other campers and boaters about being wastewater smart!

Other tips

  • When traveling, use restroom facilities in parks and rest areas as often as possible.
  • Empty holding tanks only when they are full to decrease the negative chemical effects on septic systems.
  • Frequently clean and properly maintain your black and grey tanks to minimize odors.
  • Tell others about enzyme or bacterial-based tank deodorizers.

Additional resources


Formaldehyde is an EPA-recognized carcinogen.

Harsh chemicals found in chemical-based deodorizers destroy beneficial microorganisms that break down sewage waste, can cause soil and groundwater contamination and threaten nearby surface waters and water supply wells.

Restoration of contaminated soils and water is expensive and time consuming.

Chemical presence can cause septic system failures that can force the closures of sanitation stations until the problem can be corrected.