Hayward
Regional Shoreline Hayward Area Recreation and Park District California King Tides Bay Trail Links: Bay Trail Home Bay Trail Map: East Bay Bay Trail South Bay Map My Bay Trail Pages Legacy Guided Photo Tours (Archived): Oyster Bay San Leandro Hayward Shoreline Alameda Creek Trail Coyote Hills Dumbarton Bridge Don Edwards SFBNWR Coyote Creek Lagoon Alviso New Bay Trail Pages: Eden Landing, Hayward Palo Alto Baylands 2009 Sunnyvale Baylands (2011) Moffett Bay Trail Stevens Creek Trail (2012) Stevens Creek to Cooley Landing Shoreline Park Mountain View (2009) Guadalupe River Trail 101 to Alviso Alviso Sunset San Tomas Aquino Creek Ravenswood Port of Redwood City Redwood Shores High-Tide Pages: Palo Alto Baylands High Tide 11/26/11 Alviso King Tide Pictures, 2/9/13 High Tide at the Palo Alto Baylands 1/30/14 Facebook Albums King Tides at Alameda Creek and Coyote Hills, 1/31/14 King Tide at Don Edwards SFBNWR, Fremont, 1/31/14 |
King Tide and Low
Tide at the Hayward Regional Shoreline, 1/25/14 and 1/29/14
I went to visit the Hayward
Shoreline twice recently. Once was on 1/25/14 to see the new art
exhibit on sea level rise at the Hayward Shoreline Interpretive Center.
At that time, it was relatively low tide. Low tide was at 2:13 pm at
0.56 feet (at the east end of the San Mateo Bridge). High tide was much
later at 8:45 pm at 5.72 feet. I biked down to the shoreline and rode
partway down the shore and came back at sunset. On 1/29/14, I went back
to see the King Tide, which are the highest tides of the year. They
occur when the sun and moon are aligned to have the greatest pull on
the oceans' tides. They also create very low tides. On that day, high
tide was at 8.8 feet at 10:27 am. Low tide was a very low -1.19 feet at
5:37 pm. Below are pictures from both days, comparing the high and low
tides in approximately the same locations. Note that 1/25/14 was a
mostly sunny day. 1/29/14 was overcast. In general, if it's a sunny
picture, it's low tide. If it's a cloudy picture, it's high tide.
Looking at the effects of the King Tide helps give an appreciation of the effects of sea level rise. The level of today's King Tide could end up being the average or even low tide level in the future. Much of the infrastructure around the Bay was built with certain assumptions about the maximum water levels. If those levels are exceeded, there could be widespread damage, unless expensive modifications are made to prevent it. In the pictures below, imagine if the high tide levels were more than 4 feet higher. This is the Hayward Shoreline Interpretive Center on 1/25/14 at 3:03 pm, almost an hour after the lowest point in the tide. The Interpretive Center sits on pier pilings above a tidal marsh, which is mostly drained at this time. This is at 10:09 am on 1/29/14, a little before the high tide, so water is still rising. The marsh under the Interpretive Center is almost completely underwater. Only the tops of the highest marsh vegetation are visible. 1/29/14: This is the channel next to the Interpretive Center at high tide. The water is about a foot below the trail. 1/29/14: At high tide, the water is just a couple feet below bottom of the Interpretive Center. 1/25/14: This is the reception in
the Interpretive Center for photographer Oliver Klink (left) and artist
Jennifer Koney (center). They are standing in front of some of
Jennifer's paintings, part of an exhibit called "55" - Images of
Sea Level Rise." The paintings depict the impact of the predicted
55" rise in the level of San Francisco Bay by 2099 due to global
warming. The line on the wall and on the paintings marks the 55" level.
They are intended to illustrate how high that level is. If the sea
level today were 55" higher, the audience would be standing in several
feet of water in the Interpretive Center.
The other part of the exhibit shows Oliver Klink's photographs of Iceland and Antartica. Melting of ice in these polar regions are predicted to be a major cause of sea level rise. The exhibit lasts until April 13, 2014. 1/25/14: This is a view of the marsh from the back deck of the Interpretive Center. The wooden structure is a model of a wind-powered archimedes screw, which was used to pump Bay water into salt ponds. A larger model is in a marsh near the Bay. 1/25/14: This is the Bay Trail, leading from the Interpretive Center to the Bay. The channel on the right is mostly drained. Ahead is a fence blocking a levee road. 1/29/14: This is the channel at high tide, full of water. That's the fence blocking the levee road, seen above. 1/24/14: To the right of the Bay Trail is a large marsh with natural channels. The fenced-off levee road is on the right. 1/25/14: This is the same spot as above. The marsh is almost totally underwater. 1/25/14: This is another channel in the marsh to the north of the Bay Trail. Notice the fence on top of the marsh. 1/29/14: This is the same fence as above. It is now in the water. 1/25/14: This is the marsh north of the Bay Trail. It is the H.A.R.D. (for Hayward Area Recreation and Park District) Marsh. There are deep channels cutting through the marsh. 1/29/14: This is the same marsh at high tide, entirely underwater, with no sign of the feeder channels. 1/25/14: This is a view looking north across the H.A.R.D. Marsh, with mostly mud and vegetation visible. 1/29/14: This is a view north across the H.A.R.D. Marsh at high tide. Only the tops of the vegetation are above water. 1/25/14: This is the Bay Trail nearing the Bay. Notice the trail signboard and the marsh on the right. 1/29/14: This is the same trail signboard as above. The marsh is full of water. 1/29/14: Near the Bay, the water nearly reaches the bottom of this metal bridge. 1/25/14: This is a view east from the bridge, looking across the H.A.R.D Marsh towards Hayward. 1/29/14: This is the same view from the bridge at high tide, with water flooding into the H.A.R.D. Marsh. 1/25/14: View from the bridge, looking towards the Bay at low tide. Mudflats line the channel and shoreline. The open waters of the Bay are far in the distance. Note the signboard on the right. 1/29/14: View from the bridge looking towards the Bay at high tide. The waters of the Bay are hitting the shoreline. This is at 10:37 am, just a few minutes past the peak of the King Tide. 1/25/14: Spit of land surrounded by mudflats. 1/29/14: The same spit of land is almost totally underwater. The mudflats are covered by water. 1/25/14: Small bay and beach. 1/29/14: Same small bay, but no beach. 1/25/14: This bench provides a nice rest spot on the bayshore. There are broad mudflats and spits of land covered with marsh vegetation. In the distance is Hwy 92 leading to the San Mateo Bridge. 1/29/14: This is the same bench. The mudflats and marsh-covered fingers of land are all underwater. 1/25/14: This pipeline drains into a small bay. 1/29/14: This is the same small bay as above. The pipeline is underwater. 1/25/14: This is the southwestern part of Cogswell Marsh, a former salt pond that was opened up to tidal flow, creating a 250-acre marsh. Note the bridge ahead. A channel cuts through the marsh. 1/29/14: This is almost the same view of the marsh, with the bridge in the distance. The marsh vegetation is mostly underwater. It's hard to see where the channel is, but it can be discerned from the strip of water with no vegetation piercing the surface. 1/25/14: This sandy beach is next to a spit of land that was once the site of Johnson's Landing.. Note the big driftwood tree, which is entirely out of the water. 1/29/14: Same spot. The beach and the bottom of the big tree are underwater. 1/25/14: This is the Bay Trail bridge over the mouth of the slough flowing into the marsh. 1/29/14: Same bridge, on the Bay side. The water is a few feet blow the bridge. 1/25/14: Marsh side of the bridge at low tide. The slough is mostly mudflats, with a small channel. 1/29/14: The water is a few feet below the bridge. The slough is totally covered with water. 1/25/14: View of the marsh from the bridge. 1/29/14: View of the marsh from the bridge at high tide. 1/25/14: looking south along the bridge at low tide. The pilings are mostly out of the water. 1/29/14: Same view of the bridge. The water is much higher. 1/25/14: These mudlflats are at the wide mouth of a slough feeding into Cogswell Marsh. 1/29/14: The mouth of the slough and the shorelilne are underwater. 1/25/14: This is the long Bay Trail bridge over the inlet to Cogswell Marsh. At low tide, there is just a narrow channel under the bridge. 1/29/14: At high tide, the water completely fills the marsh inlet. 1/25/14: This is the largest section of Cogswell Marsh. The trail on the right bisects the marsh. The slough on the left provides water to the marsh. At low tide, the marsh vegetation is out of the water. 1/29/14: This is the same trail as the one above, at high tide. The marsh is flooded. 1/25/14: This is the inland side of Cogswell Marsh bridge at low tide. 1/29/14: This is the inland side of the bridge at high tide. 1/25/14: This interpretive sign is at the northeast corner of Cogswell Marsh. At low tide, there is almost no open water in this part of the marsh. 1/29/14: There is also a bench here. At high tide, the marsh is flooded. 1/25/14: North of Cogswell Marsh is a retired landfill. Between the two is this channel, which is a mudflat at low tide. 1/29/14: At high tide, the channel next to the landfill is full of water. 1/25/14: There is a triangular marsh between the landfill and the Bay. Note the deep channels crossing the marsh. 1/29/14: This is the marsh at high tide. The marsh channels are completely full. 1/25/14: This small sandy beach is on the bayside of the southwest corner of the landfill. Beyond the beach are broad mudflats. 1/29/14: At high tide, the beach and mudflats are underwater. 1/25/14: This is the same beach, but looking north along the shore. The point of land on the left is Hayward's Landing. Note the round concrete columns on the beach. 1/29/14: This is the same beach at high tide. The lower concrete column is in water. 1/25/14: This deep narrow channel runs along the north side of the landfill. 1/29/14: At high tide, the channel is filled to the brim with water. 1/25/14: North of the landfill is a flood control channel. These tide gates control the water flowing between the Bay and the channel. These are the gates at low tide. A small amount of water is flowing out of the flapper valves. The valves allow water to flow out of the channel, but not into it. The water level has to rise up to the level of the smaller holes before water flows into the channel. 1/29/14: At high tide, the flapper valves and inlet holes are completely underwater. 1/25/14: This is the inland side of the tide gate at low tide. The water in the channel is at its lowest level. It can't drop any lower than the bottom of the large holes, which lead to the flapper valves. 1/29/14: At high tide, the water is almost covering the large holes in the tide gate. The small holes are completely underwater and are allowing the Bay water to flow into the channel. There is nothing preventing the water level from continuing to rise in the channel until it reaches the same level as the Bay. 1/25/14: This is the flood control channel at low tide. To the left is a larger retired landfill. 1/29/14: This is the flood control channel at high tide. 1/25/14: This is the shoreline north of the flood control channel. Beaches and mudflats are exposed along the shoreline. The Bay is far offshore. After this, I turned around and went back. 1/29/14, 11:21 am, about an hour after the peak of the tide. This is the shoreline north of the flood control channel. The Bay waters are lapping up against the riprap-protected shoreline, drowning the beaches and mudflats. Sunset Pictures, 1/25/14 The pictures below were taken at sunset on 1/25/14, beginning at 5:09 pm. It was in-between high and low tide. This is back where the Bay Trail first meets the Bay after coming from the Interpretive Center. |