As evidenced by this picture, taken August 7th, water is back in the upstream section of the Creek alongside Bol Park, but the surface is dry by the time the Creek passes under the Tippawingo bridge.
Matadero Creek near Bol Park, August 7, 2012
The flow of water in Matadero Creek normally falls off during the summer months as runoff from rains up in the hills vanishes and natural springs dry up. Yet, in recent years, as Matadero Creek winds its way through the Barron Park neighborhood, water flow has been visible even during the summer months.
This year the water level has been particularly low. On top of this, several residents reported a sudden, overnight drop in the water level at the end of June. So, the questions are: Â in these dry months, why is there any flow at all in Matadero Creek: and why was there a sudden drop in the water level?
The answer to the first question is that water is continually discharged into the Creek from five separate treatment systems in the Research Park. These pumping stations have been operating for over a decade, as part of the program to clean up the underground contamination caused by years of leaks into the subsurface from underground tanks that held chemical solvents. The tanks were removed long ago, but the contamination they caused remains.
The treatment systems process the water that has been pumped out of the ground at about a dozen properties in the Research Park and several places in the VA property where the plume of underground contamination had spread. These locations still have unacceptably high levels contamination in the groundwater. Water from underground wells at these locations is pumped to the treatment systems, which extract the volatile organic contaminants and then discharge the cleansed water (under permits from the State) into Matadero Creek. The pumps in wells in the Barron Park neighborhood were shut down several years ago when the contamination level in the subsurface groundwater here dropped to levels below EPA drinking water standards.
The sudden drop off in the water level in the Creek at the end of June appears to be because one of the treatment sites, at 3400 Hillview, was shut down for two days, just when the drop in Matadero Creek was observed. The 3400 Hillview location is undergoing significant construction by its new owner, VMWare (previously Roche) and the senior engineer in charge of the 3400 Hillview remediation project said that electrical power to the treatment system was shut down during that two day period. The engineers in charge of the other treatment systems reported that they were operating normally. The 3400 Hillview system treats and discharges more water than any of the other treatment systems – – on average almost 900,000 gallons/month, or about 1/3 of the total discharged into the Creek. To give you an feeling for this amount, an olympic size swimming pool holds about 600,000 gallons. A more detailed story on the sudden drop in water level will appear in the upcoming issue of the Barron Park Newsletter.
Art Liberman