Sediment

Sediment is a normal part of creek ecology

Gravel and cobble-sized sediment provide valuable habitat for aquatic life, including:

  • Fish eggs
  • Larvae of damselflies and dragonflies
  • Other benthic macroinvertebrates

But too much fine sediment like sand, silts and clays can degrade gravel and cobble habitats by:

  • smothering eggs and larvae
  • clogging fish gills
  • reducing visibility for animals looking for food.

As a rule of thumb, local creek water should be clear and cool except during storm events, when the water can become cloudy with sediment that runs off the landscape.

What are the major sources of sediment?

The hills above the main campus are a major source of sediment due to:

  • steep topography
  • the fire trail system, which is comprised of dirt roads

The most concentrated sediment releases come from construction activities:

  • During storm events, when rain and runoff flow over exposed soils
  • On clear days, when some misguided contractors dispose of muddy water incorrectly into storm drains.

What can I do?

Call EH&S at (510) 642-3073 if you see:

  • Cloudy water on a clear day
  • Muddy water flowing from a construction site during a storm event 

What UC Berkeley is doing?

All construction contractors must submit a Storm Water Pollution Prevention Plan (SWPPP) designed to minimize sediment releases.

EH&S is characterizing sediment releases from the upper watershed above the main campus and will develop a strategy to reduce sediment runoff from this area.