Alviso Outing


On a fine, sunny Saturday in early spring Wayne and I decided we should hike out to check on the Alviso weep site. We have been tracking this site for about a year now and it continues to impress with entertaing diversity over time and space. On this occasion we found the weep site in its driest state yet — somewhat odd since it is our rainy season. In any event, Wayne busied himself gathering samples and data on PH and salinity for several previously sampled locations.

Wayne collecting samples

Wayne wields the pipettor while balanced on an extant plank.

One of the more interesting questions these days addresses the source of water feeding the weep. The weep clearly involves water seeping from underneath the elevated railroad bed.

Weep relationships

View of the weep and the stream on the opposite side of the railroad grade.

On this visit water salinity in the weep measured above 60 PPT. Similar readings on the opposite side of the railroad grade yielded much lower salinities — on the order of 12 PPT. Why is the weep more saline? And why does is seem to have contracted during the wet portion of the year? From where does the east side “stream” get its water? Questions abound.

Wayne checking salinity

Wayne checking the salinity of the “stream”.

For my part, I set about taking a series of plan view shots of the weep using the carp pole and then launched a kite for the larger view. It was a refreshingly brisk breeze — I’ve suffered from lackluster winds for weeks — so I had the relatively rare occasion of pullling the diminuitive Sutton 8 out of the bag. This small kite flew well in a >20 mph breeze.

Alviso Ponds

The levee separating Salt Ponds A15 and A13. Here the colors were similar to those found in a visit last August.

Later in the day, as the winds fell off, I traded it for a Sutton 16. After shooting the weep, I took a hike out between Salt Ponds A15 and A13 to take a series and later walked the kite back to Alviso as the sun was setting.


Sea gulls gathering in a pond close to Alviso.

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