Moss Control & Water Protection: Best Practices for Roofs Near Watercourses
Protect our creeks, ponds, and shorelines by choosing watercourse‑safe ways to control moss on your roof.
Many moss control products contain bleach, ammonia, or other toxic chemicals that harm fish, amphibians, and water quality when washed into storm drains or directly into streams.
What goes on your roof can end up in the water.
Why Be Careful?
✔️ Common moss killers (e.g., bleach‑based sprays like “30 Seconds”) are toxic to aquatic life even at low levels.
✔️ Runoff from roofs enters storm drains or soaks into nearby creeks and ponds.
✔️ Small changes at home help keep our watershed healthy.
✅ Recommended Best Practices
🧹 Remove moss manually
- On a dry day, sweep moss gently off shingles with a stiff broom or plastic roof rake.
- Collect moss and dispose of it in yard waste — don’t rinse into drains or the creek.
🧴 Choose water‑safe products
- Look for moss control products made from potassium salts of fatty acids, such as:
- Safer Moss & Algae Killer and Surface Cleaner
- Scotts EcoSense Moss Control
- Other options:
- Horticultural vinegar (10–20% acetic acid, use sparingly)
- Baking soda sprinkled directly on moss
- Follow label directions and avoid over‑application.
🪙 Prevent moss from returning
- Install zinc or copper strips along your roof ridge. Rainwater carries trace amounts down the roof and inhibits moss regrowth.
- Keep trees trimmed back to reduce shade and moisture on your roof.
🚫 Avoid These
- Products containing:
- Bleach (sodium hypochlorite)
- Quaternary ammonium compounds
- “Quick‑kill” moss sprays labeled as corrosive or harmful to aquatic life.
- Rinsing moss or chemicals into storm drains, ditches, or creeks.
📅 Maintenance Tips
- Inspect your roof every 6–12 months and treat early before moss gets thick.
- Work on a dry stretch of weather (48–72 hours of dry forecast).
- Plug downspouts temporarily to collect and properly dispose of runoff.
Every little bit helps.
By choosing watercourse‑safe methods, you help protect our local creeks, ponds, and the wildlife that depends on them.
For more tips on protecting water quality at home, visit: