Lafayette neighborhoods are enhanced by creeks of many sizes. Some flow year-round, while others flow only after rains. Creeks and their green riparian trees and plants provide enjoyment for us and crucial habitat for wildlife. They also capture stormwater runoff integral part of the City’s stormwater drainage system.

Most of the City of Lafayette lies within the Las Trampas Creek Watershed. Las Trampas Creek is part of the greater Walnut Creek Watershed, which empties into Suisun Bay. Rainwater and runoff flow into Las Trampas Creek via six tributaries: Old Jonas Creek, Grizzly Creek, Reliez Creek, and Lafayette Creek (which Hidden Valley Creek and Happy Valley Creek feed). Some areas along the City's Creeks lie within the FEMA 100 year flood zone. See a map of the creeks and flood zone areas within Lafayette.

The City's 13 miles of creeks are bordered by more than 1000 homes and businesses - roughly 12% of properties.

Property Owner Responsibilities

As in most cities, Lafayette property owners are responsible for maintaining the stormwater drainage system on their property to keep creeks healthy and unpolluted and to prevent flooding and erosion. The general responsibilities are listed below. A more detailed list is available on the letter that the City sends to creek-side property owners annually.

• Inspect and maintain your portion of the creek, to ensure it remains free of all debris such as grass clippings, tree limbs, leaves and waste vegetation, trash, and other objects that could obstruct the full flow of water.
  
  
• Inspect and clean culverts or pipes under your driveway and ditches along your property, especially before the rainy season begins in October and before major storms. Such actions ensure that stormwater will flow unimpeded and will not carry pollutants into the creeks.

• Maintain stable vegetated creek banks to minimize the rate of soil erosion and to prevent bank failures that may add large volumes of sediment to the creeks and can cause property damage.
  
  
• Never alter the creek without determining whether a permit is required from the State Department of Fish and Wildlife, the Regional Water Quality Control Board, and the Army Corps of Engineers, as well as the City of Lafayette.
  
  
• Ensure that all construction near the creek is approved by Lafayette’s Planning Department and complies with the City’s creek setback requirements.
  
  
• Maintain a sufficient riparian canopy of native bushes and trees to keep the creek water cool, thus avoiding growth of harmful algae and preserving animal habitats.

Those fortunate to have a creek flowing through their property are also its steward. Carefully managed and maintained creeks flow cleanly and freely between stable banks, protecting you and your neighbors’ property from damage and loss of property value.

Dealing with Erosion

Urban development has accelerated the rate of erosion within watersheds beyond nature's healing capabilities. The explosive development that Lafayette has experience since the 1950s has dramatically increased peak flows of our creeks, causing extensive property loss along Las Trampas Creek and two of its tributaries: Happy Valley Creek and Reliez Creek. High flow rates from even a single intense storm can cause significant changes in a creek bank. 

If you think you are having erosion issues along your creek bank, the Contra Costa County Private Creek Maintenance web page provides information and resources on how to properly control erosion and other creek maintenance issues. It is the property owners responsibility to maintain their creek bank and permits are required for most work along the creek banks and channel. 

The County also has a Streamside Management Program for Landowners that provides free advice to county landowners about creek care, restoration, and maintenance. Email: custreams@gmail.com

More Information

Get more detailed information about stormwater and creek-related ordinances in the Municipal Code.

Relevant codes include:

• Title 5, Chapter 5-4 discusses stormwater pollution prevention to protect the creeks.
  
  
• Title 6, Chapter 6-18 pertains to flood damage prevention and permitted construction in compliance with creek setback requirements.

Contact City of Lafayette Engineering Services Dept. (925) 284-1951 and City of Lafayette Planning Services Div. (925) 284-1976 for information on potential permits needed for project work along the City’s creeks.

Learn more about Living with Creek with this Contra Costa County brochure.