Statement of Purpose Problem: Lake Tahoe over the last few years has gained popularity, but not for its beautiful beaches and stunning water, but because of its increase in the algae population, pollution, and eutrophication (the overabundance of nutrients). It has not only affected the quality of the water, but the color as well. It has started to become less and less blue because over the unnecessary abundance of algae taking over the water and the sediments from human activity. Phytoplankton are also affected. They live in oceans, seas, and lakes. Phytoplankton live at the top of the water column, as far down as the sun can penetrate. The algae in these areas are affecting the Phytoplankton greatly. Without sufficient sunlight the Phytoplankton are dying and being reduced in numbers immensely. Previous Attempted Solutions: The primary anthropogenic (human cause) sources are accelerated erosion, fertilizer use, car exhaust and urban runoff. Excessive automobile use degrades air quality in the Basin and contributes to the decline in Tahoe’s clarity. Ride your bike, walk, carpool, take the trolley, ski shuttles or use public transportation. Stay on trails when you hike or bike. Straying from the trail causes erosion, one of the key problems causing Lake Tahoe’s declining clarity. Use native plants when landscaping. Native or adapted plants are easier to maintain, require little irrigation, and little or no fertilizer. Excess fertilizer from landscaping practices can flow into Lake Tahoe and feed algae. Most of the solutions they are doing aren’t helping the algae problem but trying to keep the people from polluting the lake. We want to do something more biotech related to make a permanent solution. Current Limitations: Lake Tahoe is currently losing its clarity. The lake is becoming increasingly green opposed to blue. This can be attributed to the levels of algae. The levels of phosphorus in lakes contributes to the amount of algae. When the phosphorus increases, so does the algae. If a plan was put in motion to reduce the amount of algae in Lake Tahoe, there would also have to be a plan to rid the lake of phosphorus. Sources such as fertilizer, pet waste, stormwater runoff, and agriculture can impact the amount of algae in the lake. These sources would have to be decreased in order to reduce the amount of algae. Proposed Solution: Our idea is to remove the increasing amount of algae blooms that are affecting the water quality/color of Lake Tahoe by creating a bacteria that would break down the algae and be large enough to be filtered out after the job has been finished. This operation should only be needed occasionally because the phytoplankton in Lake Tahoe will thrive with the algae gone and prevent it from coming back for a long while. We formulated this solution from a study by UC davis, it said that the increase in growth in algae is believed to be due to a reduction in the size of the phytoplankton in the lake, overabundance of nutrients, and human activity sources.The primary human activity sources are accelerated erosion, fertilizer use, car exhaust and urban runoff. Citations: http://terc.ucdavis.edu/ed-outreach/documents/docent-training/4science-research.pdf https://keeptahoeblue.org/beblue/ http://www.waterboards.ca.gov/lahontan/press_room/press_releases/docs/pr090210.pdf http://www.ecy.wa.gov/programs/wq/plants/algae/lakes/LakeRestoration.html https://www.ucdavis.edu/news/keep-tahoe-blue-less-algae-not-clarity-key-factor-blueness
Virtual Mentor and Credentials: Our chosen mentor is Dr. Darcie Goodman Collins. She is a PhD and is the executive director of the official Keep Tahoe Blue league. Collins earned her doctorate at the University of California, Santa Barbara and has previously served as Habitat Restoration Director for Save the Bay. Mentor Feedback Our mentor emailed us back and had amazing feedback. He gave us ideas to work off of.
Dear San Marin students, Thank you for your email and for your interest in helping to protect Lake Tahoe. Your proposed project is indeed interesting, but may I suggest an alternative approach to reducing algal blooms in Lake Tahoe. Algae, as you know, are prominent in any water body, and are a vital part of the ecosystem; thus it is not the algae that is the problem, but the blooms of algae. Which is to say that removing algae will not solve the problem of algal blooms. In order to reduce the extent of algal blooms we need to address the root causes of these blooms, which are increased nutrients (namely phosphorus) and warmer nearshore waters. The latter is more difficult to address as it is due to low water levels in recent drought years and climate change. The former, however, can be addressed, as increased nutrients are almost entirely from human activities – as you noted below: “sources are accelerated erosion, fertilizer use, car exhaust and urban runoff”. Of these, urban stormwater runoff is the largest source of phosphorus entering Lake Tahoe. Considering that urban stormwater runoff is the greatest cause of increased algal blooms in the Lake, may I suggest a solution at the source, either by controlling individual sources of phosphorus (e.g., fertilizers) or removing phosphorus from stormwater outfalls. I could imagine, for example, filters at each stormwater outfall containing a microorgamism that consumes all phosphorus from stormwater before it enters the Lake. That said, I would be the first to admit I am not an engineer, so when it comes to the actually design of such a filter or related infrastructure I would not be the best to advise. But with regards to nutrient cycling and addressing the root causes of perceived increases in algal blooms in the Lake I would be happy to answer any more questions you may have. Best of luck with your project and thank you for helping to Keep Tahoe Blue. Regards, Zack
Reflection My group consisted of me, Annabel, Ely, and Mariana. We were given a project in our biology/biotech class where we had to find a biotech solution for a problem we want to solve or help. This project was really fun and gave us a lot of room to think creatively, while including research. We all worked really well together. Two things we did really well was communicate, and split up the work while researching and putting together our project. Two things we could improve on were managing our time better and having more of an opinion when it came to the decision of our topic. I really enjoyed this project and thought it went really well.