How You Can Prepare for the Rainy Season

The rainy season is here and it is never too early to be prepared.

Because San Francisco has a combined sewer system that collects and treats stormwater in addition to what is flushed down the toilets and goes down the sinks, the SFPUC ramps up its storm preparation and response efforts in advance of and during the rainy season.

SFPUC crews respond to areas where storm drains are clogged.

SFPUC crews work every day to protect public health and the environment by maintaining and upgrading critical sewer system infrastructure, inspecting and cleaning sewer pipes and catch basins (over 4,000 cleaned over the last year) so that it is prepared for the rain. And while the SFPUC prepares its wet weather operations, it also encourages residents and businesses to do be prepared and take steps to protect their property from storms and the risk of flooding.

  • Protect your property: regularly inspect and maintain your sewer lateral (the connection from your building to the city sewer). Tree roots, “flushable” wipes, and grease poured down the drain can clog your sewer pipes and can cause backups.
  • Get free sandbags from San Francisco Public Works.
  • Report to 311 if you see clogged catch basins, street flooding, sewer backups or wastewater odors.
  • Elevate belongings in your garage and any low-lying areas on your property. Remember to store emergency items, such as first aid kits, flashlights and portable radios, in a safe and high place.
  • Purchase low-cost National Flood Insurance.
  • Apply for a Floodwater Grant to flood-proof your property. 
  • Learn what you can do if a backup or flooding does occur.
Sandbags near storm drains in preparation of the rain.

In a combined sewer system, managing stormwater across the City, it is an important priority for the SFPUC to minimize the burden on its combined sewer system’s capacity, increasing flood resilience, and greening neighborhoods. In addition to the work the City is doing to install rain gardens and other green infrastructure technologies where appropriate, the SFPUC encourages exploring ways that can help manage stormwater:  

  • Learn more about the Green Infrastructure Grant Program
  • Use rainwater to your advantage:
    • Increase green space and use permeable pavements for parking and patio areas to let more rainfall drain into the soil, leaving more room in sewers during storms.
    • Consider connecting your downspout to a rain barrel or cistern to capture and save rainwater for later uses, such as watering plants or washing walkways.
  • Adopt a Drain or become a Rain Guardian