Wednesday, October 13, 2010
Wednesday, December 23, 2009
Bridge Deck
It's gone. The culvert that is. Now Sequim Bay and its associated fish have full access to this gem of a salt marsh! Located a little over 3 miles from the mouth of Jimmy Come Lately Creek we'd expect alot of juvenile summer chum to be moving along this shoreline starting in February, and we hope they'll enjoy the access to the saltmarsh. Now we need to get folks access to their road, so in goes the bridge.
A last look at the estuary mouth before it gets hidden under the bridge. The flow you see here is typical year round at the site. It's low tide in this shot, so the saltwater has drained from the marsh and the water in the channel is moslty groundwater exiting from area springs. 
The bridge arrives on 5 semi-trucks in sections called girders. They're like giant leggos...much of the cement work has been like leggo land come to think of it.
The resident ducks didn't mind the commotion. Watch your toes!
As usual for this project we began loosing daylight and finished in the dark.
Tadumm! It's just that easy, the bridge is set.
A last look at the estuary mouth before it gets hidden under the bridge. The flow you see here is typical year round at the site. It's low tide in this shot, so the saltwater has drained from the marsh and the water in the channel is moslty groundwater exiting from area springs. 
The bridge arrives on 5 semi-trucks in sections called girders. They're like giant leggos...much of the cement work has been like leggo land come to think of it.
The resident ducks didn't mind the commotion. Watch your toes!
As usual for this project we began loosing daylight and finished in the dark.
Tadumm! It's just that easy, the bridge is set.
Tuesday, December 15, 2009
Culvert Removal
The day has finally come where we get to take out the culvert. We waited for a low tide and once most of the tidal waters had drained from the estuary we installed a simple diversion of the freshwater flowing from the estuary and pumped it around the construction area to the beach. 
Without water flowing through the area, work became a matter of getting the old road fill and culvert out of there and bringing in the new. Only it wasn't that simple, because the road fill was layers of unsuitable fill and layers of nice beach sands and gravels we could use to construct our channel. Unsuitables left the site but the precious beach sands were set aside for later in the evening. In order to reach the center of the excavation excavators worked from both bridge abutments.
We wanted to maintian the meander of the tidal channel upstream of the culvert, so special attention was paid to holding this bank in place. We will plant this bank with saltmarsh vegetation plugs and the biodegradable coir mat will collect drifting seeds and turn into a saltmarsh Chia Pet.
The channel area was over excavated and then filled with a special mix of washed sand and rock for the channel floodplain, while the preserved beach sands were used to construct a channel down the center.
Oh, did you notice it is getting dark, those winter low tides like the darkness. Once the channel was built we stopped the diversion and let Pitship Estuary drain freely for the first time in at least 50 years.
Without water flowing through the area, work became a matter of getting the old road fill and culvert out of there and bringing in the new. Only it wasn't that simple, because the road fill was layers of unsuitable fill and layers of nice beach sands and gravels we could use to construct our channel. Unsuitables left the site but the precious beach sands were set aside for later in the evening. In order to reach the center of the excavation excavators worked from both bridge abutments.
We wanted to maintian the meander of the tidal channel upstream of the culvert, so special attention was paid to holding this bank in place. We will plant this bank with saltmarsh vegetation plugs and the biodegradable coir mat will collect drifting seeds and turn into a saltmarsh Chia Pet.
The channel area was over excavated and then filled with a special mix of washed sand and rock for the channel floodplain, while the preserved beach sands were used to construct a channel down the center.
Oh, did you notice it is getting dark, those winter low tides like the darkness. Once the channel was built we stopped the diversion and let Pitship Estuary drain freely for the first time in at least 50 years.
Pile Caps
Pile Driving time at Pitship! Because of the soft marine sediments in the area our abutments will be cast around piling. Geotech investigations indicated we would need to drive piling nearly 40 ft to get good bearing, but we got lucky and ended up with bearing strength at about 25 ft. The extra piling is cut off, the driven piling filled with cement and rebar.
Controlled density fill (basically weak concrete) is poured around the piles and used as a base for the form work for the pile caps. You can see the connection between the piling and the pile cap in the bottom of the form.
The form gets filled with concrete, the surrounding area filled with CDF, and we are ready for the next phase of our project...culvert removal and channel construction!
Controlled density fill (basically weak concrete) is poured around the piles and used as a base for the form work for the pile caps. You can see the connection between the piling and the pile cap in the bottom of the form.The form gets filled with concrete, the surrounding area filled with CDF, and we are ready for the next phase of our project...culvert removal and channel construction!Thursday, December 10, 2009
Let's Get Cold and Dirty!
Excavation began at Pitship Pocket Estuary. The first part of the work is to remove the road fill bordering the culvert and building the bridge abutments. Work is taking place at night to take advantage of nighttime low tides. Here's a look from the upstream end of the culvert with work under way!
November is a cruel time for night work, we have weathered a few gales in the first few nights of the project. Not sure if you can make out the sideways rain in this shot. The foreman looked up at me from the bottom of the excavation "Sure wish we were building this in August!" as the water from his hard hat ran down the back of his neck. Sometimes you have the play with the cards yer dealt...brrr...
Monday, November 16, 2009
Pitship Estuary Project Underway!
The North Olympic Salmon Coalition (NOSC) is starting a new estuary restoration project at the Pitship Estuary, an intertidal wetland located on the western (i.e., interior) side of West Sequim Bay Road, approximately 0.3 mile south of Pitship Point. A principal focus of the effort is to improve water movement between the estuary and the main body of Sequim Bay, immediately to the east of West Sequim Bay Road. The project is designed to replace an undersized culvert at the estuary mouth with a bridge to restore fish access and restore tidal connection to the estuary.
Dedicated to Restoring Salmon Habitat....
The environmental conditions within the marsh are degraded due to fill and because the culvert connecting Pitship pocket estuary to Sequim Bay is undersized. This inhibits the natural rise and fall of waters within the estuary on each tidal cycle and creates a fish passage barrier due to high flow rates. The culvert is prone to clogging which can back up water in the estuary on falling tides or prevent water from entering on rising tides.
This project fits into the Sequim Bay ecosystem restoration as a critical component of non-natal juvenile summer chum and Chinook rearing habitat improvement, forage fish spawning improvement, shellfish habitat improvement and restoration of nearshore processes.
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