City Launches New Stormwater Website for Regulatory Compliance, Public Access

The City of Pasadena Public Works Department has launched a website providing centralized access to information about stormwater and urban runoff programs, supporting compliance with federal Clean Water Act requirements.

The website, is available at: cityofpasadena.net/public-works/stormwater/

It consolidates information about Pasadena’s stormwater management system into a single platform. It serves the City’s compliance with its Municipal Separate Storm Sewer System (MS4) Permit, which regulates how municipalities manage stormwater discharges to protect water quality.

For residents, businesses, and developers, the site offers a one-stop location for permit requirements, pool discharge rules, construction best practices, and details about the City’s stormwater infrastructure. The system includes 140+ miles of pipes and channels, 1,351 catch basins, and approximately 1,700 manholes, with 725 miles of streets swept biweekly.

The website explains how urban runoff affects local waterways including the Arroyo Seco, Rio Hondo, Rubio Wash, and Alhambra Wash, which flow to the LA River and Pacific Ocean. When rainwater flows over streets, parking lots, and roofs, it picks up pollutants including litter, pet waste, pesticides, fertilizers, and motor oil before entering storm drains.

The City’s stormwater mission focuses on protecting the community and environment by managing stormwater and urban runoff to prevent pollution, reduce flood risk, and safeguard local waterways while promoting a sustainable future.

Key program areas highlighted on the website include Stormwater Regulations and Pollution Prevention Programs, Stormwater Capture and Treatment Projects, the Watershed Management Program and Stormwater Master Plan, and the Safe, Clean Water Program.

The Safe, Clean Water Program, known as Measure W, was approved by Los Angeles County voters in November 2018. It invests approximately $280 million annually into stormwater capture projects through a parcel tax of 2.5 cents per square foot of impermeable area.

The website includes monitoring data dashboards, project dashboards, and an events calendar for upcoming meetings and stormwater-related activities. Quick links provide access to Pasadena Municipal Code Chapter 8.70 governing Stormwater Management and Discharge Control, educational fact sheets, pool discharge requirements, and construction best management practices.

The MS4 Permit, issued under the National Pollutant Discharge Elimination System program, serves as the primary regulatory framework guiding stormwater management activities in Pasadena. The Los Angeles Regional MS4 Permit covers 99 municipal permittees across Los Angeles and Ventura Counties.

The website provides educational content about how stormwater flows through the City, the impacts of stormwater pollution, regulatory obligations, and the shared responsibility of protecting water quality. Sections address specific audiences including residents, students, construction professionals, and industrial and commercial businesses.

For additional information, residents can contact the City’s Stormwater Program Administrator at: SWAdministrator@cityofpasadena.net.