Measuring Pollutant Removal

Measuring Pollutant Removal Efficiency of the Ballona Creek Rain Garden, Culver City, California.

Project Description:

The Culver City Rain Garden is a 300 X 3 m biofiltration rain garden system capturing and infiltrating storm water runoff from 11.1 ac of adjacent industrial and commercial properties along Jefferson Blvd. in Culver City.  Runoff from these facilities is collected in the garden where harmful pollutants and metals are sequestered and water is infiltrated back into the ground.  When the garden fills during storms greater than ¾-in, runoff is discharged into Ballona Creek where it flows to Santa Monica Bay.  To assess the effectiveness of the garden, three to four storm events were sampled during the past two rainy seasons (2015-16, 2016-17). Compound 90° V-notch weirs (Grant & Dawson 1995) outfitted with Hobo water level sensors were inserted into five inlets channeling water into the garden and two outlets that discharged water into the Creek when the garden became full.  During each storm event, Hobo data loggers were used to record water flow in the inlets and outlets, and a suite of samples were collected two to three times during the events to test for concentrations of fecal indicator bacteria, metals, gas and hydrocarbon compounds, total suspended sediments, and turbidity.  All concentration and flow data from the two seasons of sampling are now ready for analysis. Pollutant removal efficiencies will be assessed for each storm event by comparing loads for each pollutant category entering and leaving the garden.  Mean loading of these pollutants will be calculated by integrating flow and concentration data using the summation of load method (Erickson et al. 2010). This has been a cooperative study with contributions of materials and supplies from The Bay Foundation and CURes, and has included LMU faculty from the Departments of Civil Engineering & Environmental Science, Biology, and Chemistry. In 2016, a $10,000 grant for testing materials was received by John Dorsey from the Metropolitan Water District of Southern California, World Water Forum.

Advisor: John Dorsey, jdorsey@lmu.edu
Project Duration: Summer 2017 - Spring 2018

Student Duties:

The student's duties will include (but will not be limited to):

  • Conducting data assessment and statistical analyses including developing hydrographs and calculating loading estimates.
  • Presenting results at the Graduate Research Conference for the Seaver College of Science & Engineering, and at other scientific conferences as appropriate.
  • Acting as one of the authors in preparing a manuscript for publication in a peer reviewed journal.
  • Assisting with planning for any further studies that develop from this study.
  • Producing his/her thesis.
  • Assisting with data management

Student Background Required:

This project would be ideal for students with a science background, environmental engineering, or both.