FAQs

Is there a light at the end of your culvert?

  • Living on Bethel Island is different from living in Concord in more ways than one.  The island’s topography is quite flat.  People have described Delta islands as dirt bowls surrounded by water.  Bethel Island can be compared to a 3500-acre pizza surrounded by sloughs.  The crust around the edge is our levee.
  • The flat topography does not lend itself to rapid drainage.  Rain water and levee seepage water gather in the drainage ditches and slowly flow to the main canal and west across the island to the pump station at the end of Taylor Road.
  • The whole island is below sea level — anywhere from minus 5 feet to minus 20 feet.  The water in the sloughs is above sea level and exerts a constant pressure against the levee.  The water from the sloughs seeps through the levee all year round.
  • This levee seepage has to go somewhere.  That is why we have open ditches along the roads and along the levee on the North-West backside.

What are toe ditches?

  • The ditches you see along the roads are called toe ditches and are very important for levee stability.  Levee seepage has to get into the ditch and get carried away and pumped off the island.  If the seepage has no where to go, the levee foundation can become unstable.
  • Cities may have storm water drainage systems under their sidewalks and streets, but on Bethel Island, we need our open toe ditches for levee safety as well as collecting and conveying storm water when it rains.

What are culverts?

  • When development began on Bethel Island, residents were issued permits to build their driveway entrances over the existing toe ditches by installing 20-foot culvert pipes.  This allowed the water to continue to flow through the ditches and to the main canal.  Unfortunately, two things began to happen.
    • First, culverts were not kept clean and they plugged up or collapsed.
    • Second, homeowners started filling in the toe ditches to make more room for parking or to plant trees or shrubs.  These actions have stopped the water from flowing smoothly from one property to the next.
  • It is not the responsibility of BIMID to clean culverts.  The culverts are for the convenience of homeowners.  Every winter there are complaints about water backing up in neighbors’ yards and water flooding the roads.  If this is a problem in your neighborhood, it is time to clean your culvert or restore the toe ditch so it can perform its important function of collecting levee seepage.
  • BIMID’s Ordinance 4 deals with drainage and makes it illegal to block a drainage ditch or fill one in.  Culverts must be 18 inches by 20 feet.