West Carter Avenue Road Closure

Begins the Week of August 24, 2026

Beginning the week of August 24, West Carter Avenue will be closed within the active construction area beginning at North Grove Street. The North Grove Street/West Carter Avenue intersection will be closed.

The intersections of West Carter Avenue with Oak Crest Drive and North Lima Street will remain open. North Lima Street will also remain open.

The initial closure is expected to last approximately four to five weeks for water main installation. Additional traffic restrictions may be required during subsequent storm drain work.

Please use alternate routes and allow additional travel time. Emergency services access will be

Stormwater

Sierra Madre's storm drain system carries rainwater and urban runoff from streets, gutters, and catch basins toward local waterways. Unlike wastewater from sinks and toilets, stormwater generally does not go to a wastewater treatment plant before entering the environment. Keeping trash, chemicals, oil, pet waste, landscape debris, and other pollutants out of streets and storm drains helps protect local and downstream water quality.

Report a Stormwater Problem

Report a Storm Drain or Runoff Issue Report a clogged storm drain, suspected illicit discharge, runoff concern, or other stormwater issue to Sierra Madre Public Works.
LA County Stormwater Resources Access regional stormwater pollution information, illicit-discharge reporting resources, and pollution-prevention guidance from LA County Public Works.

Help Protect Our Storm Drains

Trash & Debris Keep litter, leaves, yard waste, and other debris out of streets, gutters, and catch basins.
Oil & Chemicals Never allow motor oil, antifreeze, paint, cleaners, pesticides, or other chemicals to enter the storm drain system.
Landscaping Prevent irrigation runoff and avoid applying fertilizers or pesticides when rain is expected.
Pet Waste Pick up pet waste promptly and dispose of it properly so bacteria and nutrients are not carried into waterways.

Remember: Storm drains are designed to carry stormwater. Dumping wastewater, chemicals, trash, automotive fluids, or other pollutants into a street, gutter, catch basin, or storm drain can pollute downstream waterways. For stormwater questions, contact Sierra Madre Public Works at (626) 355-7135.

When it rains, water flows across rooftops, driveways, parking areas, sidewalks, and streets. Runoff enters gutters and catch basins and is conveyed through the storm drain system toward downstream waterways.

As runoff moves across developed areas, it can pick up pollutants such as litter, motor oil, metals, fertilizers, pesticides, pet waste, sediment, and other contaminants. These materials can then be transported through the storm drain system into rivers and other receiving waters.

Storm drains and sanitary sewers are different systems. Water entering the storm drain system generally does not receive the same treatment as wastewater carried through the sanitary sewer system.

Everyday activities can affect stormwater quality. Residents and businesses can help protect local waterways by preventing pollutants from reaching streets, gutters, and storm drains.

Around Your Property

  • Sweep driveways and sidewalks instead of washing debris into the street.
  • Keep leaves, landscaping waste, and trash out of gutters and catch basins.
  • Prevent irrigation water from running off your property.
  • Pick up and properly dispose of pet waste.
  • Store chemicals, fertilizers, pesticides, and other materials where spills cannot reach the storm drain system.

Vehicles and Automotive Work

  • Repair fluid leaks promptly.
  • Recycle used motor oil and automotive fluids at an appropriate collection location.
  • Never pour oil, antifreeze, cleaners, or other automotive fluids into a gutter or storm drain.
LA County Pollution Prevention Resources

Sierra Madre's municipal stormwater program is regulated under the National Pollutant Discharge Elimination System (NPDES). The current Regional Phase I Municipal Separate Storm Sewer System (MS4) Permit is Order No. R4-2021-0105, administered by the Los Angeles Regional Water Quality Control Board.

The permit establishes requirements for municipal stormwater and certain non-stormwater discharges and requires participating agencies to implement pollution-prevention, monitoring, development, inspection, reporting, and watershed-management programs.

Rio Hondo / San Gabriel River Watershed

Sierra Madre participates in the Rio Hondo/San Gabriel River Watershed Management Program with neighboring jurisdictions and regional agencies. The Los Angeles Regional Water Quality Control Board approved the current Rio Hondo/San Gabriel River Watershed Management Program on October 15, 2025.

Stormwater planning, watershed-management, monitoring, and regulatory documents are maintained by the City and the Los Angeles Regional Water Quality Control Board. Use the resources below to review current monitoring information and regional program documents.

Sierra Madre Stormwater Monitoring Data View the City's currently posted stormwater monitoring information.
Regional Stormwater Plans and Documents Access current Rio Hondo/San Gabriel River Watershed Management Program documents from the Los Angeles Regional Water Quality Control Board.

Contact Us

232 W. Sierra Madre Blvd.
Sierra Madre, CA 91024

(626) 355-7135

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