Dam Project Part 2 July 1, 2020

Looking East 

Western Buttress grading complete waiting to be seeded.

Looking East from middle of Dam Rd.

Eastern Buttress completed waiting to be seeded

Looking East from the middle of Dam Rd.

On right all of the original limestone facing blocks have been replaced up to the road grade.

The Dam Rd is filled and compacted. Paving scheduled for sometime in August once all the revetment stone is brought in for the lower valve house channel, sand for the old gate house fill and any final fill/top soil for the area between the new valve houses.

Looking South from base of dam. Shown the bulkhead installed in buried old outlet channel that conveyed water from the old gate house into the original outlet channel.

The 2 white pcv pipes protuding through the bulkhead run up to the old gate house and will be to grout the buried channel.

The black pipe submerged and to the left is a new collection/drain pipe installed in the base of the old gate h

Looking South again from base of dam.

Shown on bottom of photo is the new bulkhead described above. 

Directly above that is the old gate house with the top removed for painting and plywood sheet temporarily attached. 

At the very top of the photo that is very light colored is the upper new valve house.

Looking South from the base/toe of dam. 

Two new solar arrays installed that will generate electricity to operate the flow monitoring equipment in the weir boxes  and security cameras.

Two of the gate actuators in the low level valve house. The actual 20 inch valves are below the grating.

These actuators will be powered by a portable generator located at the outside of the upper valve house via buried power cable. They can also be operated by hand with the attached hand wheel although very slowly.

Looking North. This is the lower level works.

On the left with black sealer on the bottom is the lower level valve house.

On the "back side" is the stilling basin which is part of the energy dissipation system.

The concrete form running east and west is the Side Spillway.

In the fore ground is the Weir Box Chamber with an access ladder.

Looking West at the "back side" North side of the Lower Level Valve House.

Shown is the stilling basin with baffles built in. Water will be discharged through the 20 inch valves and these concrete baffles are used to dissipate the energy in the rushing water before it enters the side spillway.

The top left of picture is an I Beam supporting the grating attached to the valve house.

Looking East from the "back side" North side of the lower level valve house showing grating which looks down to the 22 inch pipes discharging into the stilling basin baffles and then into the side spillway dropping into the revetment/stoned lined spillway.

On the top right is the new Weir Box Chamber with access ladder. 

Looking East.

Close up of the Weir Box Chamber on the right with the grating installed.

On the left is the new revetment/stone added to the old channel. The revetment is also used as an energy dissipater and to prevent scouring of the bottom of the old channel floor from large volume of water during a drawdown.

Looking North.

On the left is the wall of the side spillway where water will dump into the revetment/stone old spillway channel that ultimately flows into the wetland and the beginning of Limestone Creek.

Inside the Weir Box Chamber showing 6 of 7 weir boxes that will monitor the flow from these boxes with electronics. The flows monitored will be from various collection pipes and manholes installed underground during the project. Trivia- the elevation of the floor in this chamber is 64.05 feet below crest elevation.

The #1 Weir box is at the base/toe at the middle of the dam which is shown earlier. 

Looking East at the western buttress seeded. The road in the middle of the picture is the access road to the upper valve house.

On the very left along the tree line just barely visible is the access road to the lower valve house works.

BEFORE

Western Buttress - October 5, 2019

This was in the very early stage in the fall 2019 when the contractor was mobilizing and began removing stumps left from tree removal the year before. 

The year before, fall of 2018, the State had a contract for clearing a large number of trees. They were located along the left side where the black silt fencing is. The trees and their roots were impacting the

Looking east showing revetment/stone installed in front/waterside of the overflow spillway to reduce erosion.

The structure is subject to wind and wave erosion, debris loading and scour during high flow events as well as ice loading during non-navigation season. Over time this continued weathering, erosion and loading could lead to settlement and displacement of the spillway crest which would aff

Lower Valve House Works completed looking North from Upper Valve House

Upper Valve House completed. Looking East with Solar Array on left to supply electricity for lights, electronic monitoring and security.

Middle is a generator that will be used to operate the large 20 inch valves in both Valve Houses.

On right is the Upper Valve House.

Western Buttress Completed.

October 18, 2020

Aerial View of Completed Dam 

Looking West from the East side

Photo Courtesy of Donald Schmidt 

Completed Overflow Spillway showing installed decorative safety fencing installed.

Looking North from Dam Rd

Overflow Spillway From the Eastern side looking North West showing new decorative safety fence mounted on top of the new overflow spillway.

Also note one contractor construction trailer has already been removed. The one shown is scheduled to be removed within a week. 

The solar array assembly on the pole is for instrumentation power, security camera and communication equipment sending data to the Ca

Spillway from the western side looking South East

Middle of new spillway from the Eastern side Looking West showing new decorative safety fence.

One contractors site trailer has been removed and the final one scheduled to be removed within a week.

From Eastern side of Dam Road looking West

From Dam Road looking North at new overflow spillway and the Canal Corporation security fence for site access.

Looking southwest from the east side of the spillway near the bottom up at the bend showing the decorative safety fence mounted on top of new overflow spillway.

A close look at the bottom right you can see the original spillway stone work where the new spillway was built within its confines.

Looking south west from the bottom of the new spillway chute showing new fencing and wing walls meeting the old spillway drop.

From the bottom of the new overflow spillway chute looking southwest up towards the bend.

Looking North from the base of the overflow spillway.

More revetment (stone) added to the toe (base) of the spillway to act as an energy dissipater to prevent scouring and the formation of a "pool".

The flow heads north and east a few hundred feet where it meets the discharge from the siphon pipes from the lower valve house in the middle of the dam forming Limestone creek.

Looking east from the overflow spillway showing the completed buttresses and the two new access roads to the upper and lower valve houses.

MARCH 5, 2021

Photo Cortesy of Angelo and Julie Costantini 

Looking north from the dam at the lowlevel valve house and outlet channel. One gate is open. Flow is dumping into the channel. It appears that the flow is through the revetment/stone as designed.

The solar power array in the foreground.

 MARCH 5, 2021

Photo Cortesy of Angelo and Julie Costantini  

Same as above, looking north from dam road showing low level valve house, lower solar power array and outfall channel with flow.

MARCH 5, 2021

Photo Cortesy of Angelo and Julie Costantini

Zoomed photo of flow in the outlet channel.  

It's working!

Looking north from the base of the new spillway. Level at crest or slightly below. The state considers crest, 1279.8 elevation as crest.

The spillway is "tipped" lower on the east side compared to the west side due to settling through the years about 2-3 inches.

This is why water was going over about one half of the spillway a week ago.

Flow under Dam Road through the new spillway chute. Level at or almost at crest.

Looking North from the base of the new overflow spillway showing flow from the overflow spillway at approximately crest.

The new Revetment stone installed last year is handling the flow nicely. Note the flow starts going through the stone due to it's thickness, about two to three feet thick and emerges at the end downstream. 

March 30, 2021. Reservoir at or just below crest. Looking west from Dam Road at the high side (by 2-3 inches).

Extremely windy south wind causing whitecaps at the dam aiding water to go over the full spillway surface.