On this after-school lesson at Bay View Elementary School, students have been exploring the phenomenon of how and why there can still be water flowing in the San Lorenzo River even though it has hardly rained in five months. Using sponges, buckets of water and native plants in 1-gallon containers, students discover that less water drips out from the bottom of the container than they poured in, and that water is still dripping out very slowly from the plant’s container after ten minutes. Naturally, the students ask if they can use the sponges to “test” how well some of their friends absorb water. A few volunteers, including Sofia, line up to experience how much water the soil and healthy roots of native plants (sponges) can hold as it slowly seeps into the river (onto a giggling Sofia’s hair) over time. As the giggles simmer down, we share our conclusions together – healthy soils and native plants can store water and release it slowly all the way through the summer. That’s one reason why the river has water even when it hasn’t rained.
In closing, students are asked where the water we used in this lesson came from. “The sink.”
And where does sink water come from? “The pipes.”
And where do the pipes get water from? “The river?”
And where does the river get its water in the summer? “The soil and the plants!”
And where do the plants and soil get the water? “The rain!”
So, where does the sink water really come from? “It’s the winter rain!”
As we prepare for the upcoming rainy season, CWC’s Watershed Rangers are happy to tell you about the pathways rain take after it falls from the clouds over the San Lorenzo River Watershed. We are excited for rain to make our soil loose and workable for youth to plant native species along CWC’s San Lorenzo River habitat enhancement site during Youth River Health Day field trips. We look forward to a wide-open river mouth and high river flows so we can continue to learn about the migration of steelhead trout. With the rains, our mountain forests, city parks, and cracks on campus blacktops become verdant ecosystems that beg to be observed and monitored. This is going to be the best winter ever!