Students say construction destroying pond
OAKLEY: Debris from new neighborhoods in surrounding area flows into basin, killing ecosystem
By Paula King
CONTRA COSTA TIMES
Sunday, July 30, 2006
A few months ago, the pond at Freedom High School was teeming with life as a thriving habitat for egrets, turtles, fish, worms and burrowing owls.Today, portions of the pond no longer support life and the overall wetland environment has deteriorated. The school's environmental science students and teachers believe they know why. Their research findings, included in an urban runoff study funded by the city, conclude that the rapid growth in Oakley and Brentwood has led to the decline of the pond and the overall Marsh Creek watershed in far East County.
"If you look at the creek, it looks like chocolate milk," Freedom science teacher Tom Lindemuth said. "I think a lot of it has to do with construction."
Once surrounded by vineyards and orchards, the land around the campus at O'Hara Avenue and Neroly Road is now dominated by several large housing tracts. The creek and pond are laden with silt, algae, sediment and pollutants, according to the study.
The students sampled water and invertebrates and conducted experiments. They also discovered visual evidence of sand, paint and plant matter entering the storm drains of newly constructed neighborhoods surrounding Freedom High.
"All I really knew was that it was not supposed to look like that," said Freedom junior Rhiannon Merrill. "I was very excited when we got our pond and it is just deteriorating so quickly." The students act as guardians of the pond, which has been their outdoor classroom for the last few semesters.
Friends of Marsh Creek Watershed coordinator Anne Littlejohn said the students' findings could be a snapshot of what is happening to the Delta as a whole. The creek flows through Brentwood and Oakley before draining into Big Break on the Delta.
"It is so critical that we understand the changing conditions in that pond as well as Marsh Creek and the students are doing an awesome job," Littlejohn said. "We feel that it is very important to educate the public on ways to protect and restore our local watershed habitat."
As a partnership between the city and Liberty Union High School District, the pond was built as a detention basin to capture rain water and surface water from nearby neighborhoods. Oakley is partnering with the county's flood control and water conservation district to use and maintain the basin.
Tim Jensen, an associate civil engineer for the county, said he is not surprised by the amount of pollutants in the basin because some of the subdivisions were built before new, stricter state regulations on new development.
"I don't think the city intended for this pond to become a sediment and contaminated material trap. They intended for it to be a nice pond for students to do experiments in," Jensen said.
Oakley Parks and Recreation Director Nancy Kaiser said the city is taking steps to evaluate the pond and working with consultants to improve it.
Mayor Brad Nix said, "The test is how the pond is going to perform after the building is completed. Maybe we will find that this is not a good place for a pond. I think it is not realistic to think it is going to be solved during construction."
Meanwhile, the students have been monitoring and tracking water quality, fish populations and habitat growth in the pond and creek. They also complete periodic cleanups of the pond and have watched as its appearance changed from lively to 80 percent silt.
The class took measurements of the pond in May and found different results from an inlet pipe that comes from fully developed urban properties and another that leads to new housing under construction. They stated that the construction runoff was at least 10 times more turbid as the runoff from the developed site.
One section of the report reads: "based upon our observations, it seems likely that the primary amount of impact to the pond and the downstream watershed is due to operations that disturb the soil such as irrigated agriculture and housing development as opposed to runoff from vegetated cover."
Pulte Homes is a major developer in the area along the Brentwood-Oakley boundary with 511 freshly built homes in the Rose Garden subdivision and another 396 homes in the upcoming Magnolia Park development. Pulte representatives said they follow state and local regulations carefully and try to have as little environmental impact as possible.
"Even after the developers are done and the homeowners move in, there is always residual dust and we try to minimize that," said Pulte's vice president of land development Bill Sadler.
Neighboring Brentwood Park resident Bill Saleme said he is concerned about the pond's health and safety risks because of its "severe deteriorating state." With a background in construction, Saleme has offered the city potential solutions to fix the pond.
"I consider the pond a serious environmental breach not to be overlooked or disregarded," he said.
Neighboring Brentwood Park resident Bill Saleme said he is concerned about the pond's health and safety risks because of its "severe deteriorating state." With a background in construction, Saleme has offered the city potential solutions to fix the pond.
"I consider the pond a serious environmental breach not to be overlooked or disregarded," he said.
Saleme said he believes the problem lies in the pond's design. Saleme said the city should have constructed it as a detention pond with the ability for water to flow in and out.
"The (county) engineers originally designed the pond as a dry pond. The city changed and built the pond, however, as a wet pond," he said. "This difference means the inlet is lower than the outlet, the pond is deeper than a dry pond should be, the water circulation is poor and toxic waste settles as sludge."
Jensen said the basin was dry for 10 years, and the city changed it to become a community soccer field and wetlands area despite the county's reservations. He said most of the county's basins are dry this time of year and that is why the county asked the city to take responsibility for it.
"The design of a facility that holds water and keeps the water clean when it gets overwhelmed with sediment is tough to do," Jensen said.
The students and teachers involved with the study plan to launch a broader project this academic year that will investigate other areas of change such as air quality, land use, traffic and noise impacts.
"It expands on what we have done that was focused on runoff and look at the tremendous rapidization in our area," Lindemuth said. "We will tend to keep the strongest focus on the watershed where the impacts have been the most dramatic."
Paula King covers Oakley. Reach her at 925-779-7189 or pking@cctimes.com.
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