The DAM Page

Just a bunch of mill dam and turbine reference photos for your personal edification.

Although we try to be as accurate as possible, most of the comments on this page are from educated guesses. If there are any errors in terminology or whatever, please feel free to email us and tell us so.

This dam is particularly interesting in that it has a hydraulic flashboard that can be raised to increase the head height. The flashboard's hardware causes the interesting multi veiled look and would make a great modeled scene. There used to be a canal leading from the old gatehouse, which is still standing, but out of this scene to the right and now used for storage by the local public works department. The canal was filled in shortly after 1900. Evidently, the mill no longer needed hydro/mechanical power and the city didn't want to have the liability of maintenance. There is a concrete headrace and two large diameter penstocks that seem to have been added more recently, which aren't used to generate power and we can only assume at this point that it is for flood control.

This building was inundated with water half way up the first windows during the great flood of '55. Notice the wires just above the dam and to the right of the stairs just about at 4:00 from the gates. These wires hold back flashboards that are mounted on the top of the dam that gave the mill extra "head" or potential power. The wires run to and are anchored to the shore.

Cross section of the Francis style turbine and generator that was once located inside.

We assume that the gate directly in front of the camera is a skimmer gate where trash cleaned from the penstock's trash grate was pushed out and disposed of into the river below.

This is a great place to check out an old factory site. A bunch of the company's buildings were washed away during the '55 flood that is mentioned above.

This battery controlled the flow of water to the canal that ran parallel to then under the railroad tracks and fed all of the buildings south of the main buildings.

This turbine of the single runner variety is also in Collinsville, CT. We always thought that it was of the vertical arraignment (this was before we even knew there were horizontal set-ups, other than Peltons and waterwheels) and happened to be laying on it's side until we noticed the skid and the placement of the mounting feet. After more reference material became available to us it became apparent that this arraignment was actually more common than vertical installations. It was natural to install turbines in this fashion since most mills had horizontal line shafts supplying the machinery with power. The first electric power stations had alternators that were also horizontal. It wasn't until a satisfactory thrust bearing was developed that vertically arraigned alternators became widely accepted.

Some "not adjusted too often" gates. They probably took two men with pry-bars to operate.

Battery of gates that once supplied the box and crate buildings of the Collins Axe Co. The box building was washed away in the flood.

We haven't done any research on this particular site, but it seems as though the factory, which is across the street has been turned into condos, or business suites. Sorry, no pics of that.

The industrial part of the city was laid out with three canals that would supply water to the mills. The Connecticut river was dammed and water was diverted into the upper canal. Once the water ran through the turbines of the mills on the upper level it was used again by mills on the next lower canals.

Holyoke canals during the yearly drawdown. Look close and you can see water falling from the turbine's draft tube. This powerhouse is normally in use.

The following photos are what's left of two old turbines in the pit that was under the powerhouse of an old mill, which was torn down. There is water still running into both turbine's pressure housings and may be the reason that the pit hasn't been cleaned out and filled in. We're happy they didn't!

The flywheels are about 8-10 feet in diameter. One is directly connected to the horizontal turbine and the other was connected through a bevel gear set to the vertical turbine. Since a lot of energy is lost through the bevel gear arraignment it seems that the vertical turbine was in place first and the horizontal turbine was added to augment the original set-up. See update below!

This is a view of the horizontal turbine. The split housing of the vertical turbine can be seen in the bottom right of the picture.

Here's a shot of the vertical turbine's split housing. It could be a Swain turbine, but there is no way to tell for sure. There was no way to get a really good shot from the other side. By looking at these pictures it would seem that this housing is only about 4 feet across in reality it's actually much larger. More like 8 feet across.

Update: Although we are still not absolutely positive, this may be a Boyden turbine. More info can be found by clicking on the pictures below. One of the reasons we are leaning towards this is because of the lower pit construction. After revisiting the site recently (the snow finally melted) it was noticed that the area just below the horizontal turbine was circular or keyhole shaped. After re-reading French River's write up on Boyden turbines and how they were constructed, operated and that they discharged into a circular pit before exiting out the tail water tunnel, things started to come together concerning this particular turbine house remains. As mentioned above our first idea that the horizontal turbine was added later is still correct, but not just to augment the vertical one. What we envision is that originally there were two vertical Boyden turbines and one of them was eventually replaced with the HI-TEST horizontal double runner turbine. Boyden turbines were eventually phased out by better designs and mills replaced turbines with better ones as the years passed.

You can barely make out the circular wall just below the penstock. The HI-TEST horizontal turbine is to the left.

If you want to check out some great photo documentation of old mills and power houses, this is the place to go.

The picture files are BIG, really big, so get ready to wait, but they are well worth it. All the following B&W photos are from the HAER site.

After doing some research we've come to the conclusion that most of the earlier mills that had water wheels were retrofitted with much more efficient turbines by the mid 1880's. Even most of the small saw and gristmills ended up converting at sometime. However, there still were mills operating using the old "wheel" that most people associate with water power, out in rural areas, which never converted.

This picture is of a double runner turbine. The water does not exit from the ends, which caused some confusion earlier in the research, but down through the pressure housing. The iron penstock, or flume, comes in through the back wall just under the arched opening. The opening was the penstock or fore bay to the original wheel. The wheel was probably located right where the turbine sits. This is logical to assume because it would make connecting to the line shafts easier.

We found these old cut-a-ways that validate our earlier assumptions that there was a "T" or 90 degree elbows for the discharge into the Draft Tube. These two prints and a few others on this site were borrowed from the

This is a great site for those interested in hydro turbines, old and new. The company is a family owned operation that buys, owns and rebuilds old hydro electric sites around the New England area. When I say rebuilds, I mean "hands-on", everyone gets their hands dirty, literally. Right up to the president (that's her on the left). In the real world of green power some practical people are actually doing something about it and have been doing it long before global warming became vogue. More power to them!

This set of turbines is of the Francis design. The vanes or "wickets" controlled the flow. A governor is connected to the main drive shaft and controls the shaft that is mounted to the top of the housing. This would move the segment gear one way or the other depending upon demand on the system, which in turn moved the cluster of tie-rods that controlled the wickets. The rods are clearly discernable on the turbine in the background. One thing to note is that this room is equivalent to the pressure housing of the turbines in the previous photos. It should also be mentioned that the turbines in the previous photos do not use the adjustable wicket scheme of throttling. It has a cylindrical gate between the stationary vanes and the turbine runner that controls the flow of water. Is that confusing enough?

Like this. If you look into the vane section you can see the gate. There would be a "Tee" between the two turbines and the pressure housing or casing would encompass everything here except for the gate mechanism.

A shot of the same turbine from the other side. On the other side of the vertical board with the pulley, just beyond the railing is the governor. It was connected to the drive shaft by a flat belt that went around the skinny pulley next to the flywheel. The governor controlled the gate mechanism via a cable that ran through some sheaves mounted to the floor and then up and around the flat belt pulley located on the gate control shaft that runs on the outside and in front of the turbine. The "captains boat wheel" located to the front of the turbine's housing and the pulley was a manual override.

A nice powerhouse. We have plans in the making for a kit of an add on powerhouse, complete with dam gates and penstock. You supply the mill, we'll supply the power. So, keep an eye out.

The tail water discharge canal. The retaining wall must have given away and the company dumped a bunch of rubble to fill in the blank spot. This was obviously done after the mill converted from water power to all electric.

A few Tesla coils and Jacobs ladders would do wonders for this wheelhouse. If you look close at the middle archway, just below the catwalk, it is evident that the stone arch was originally much lower and was raised during the turbine retrofit. Not quite sure why two of the arches have stone voussoirs (arch stones) and the other on the left is brick.

This particular dam section is actually a spillway. Most of the time the water flows through the old penstock that once powered a mill during the 1800's.

This particular dam and pond is located in Bondsville, MA. NOTE: This site is now posted and off limits. Glad I got the shot when I did! We came across it by shear luck while driving around taking pictures after an ice storm we had a few years ago. Other than it being a cool shot, it shows a typical dam/canal layout. The canal gates are located where the vertical boards are at the mouth of the canal. The canal passes under the camera and back paralleling the river to the mill's previous location. The drop in the stonework directly in front of the camera and to the right of the dam is the spillway. Having the dam upriver and connected by a canal was necessary sometimes because the best location for the dam may not allow for the necessary head height for the mill's turbines. The canal allowed the mill to be farther downstream giving the river some distance to drop down to tail water height, while the canal remained level.

Nasty canal water. The reflected colors from the building and the greenery on the canals wall give the water a greenish-brown color, but it's actually a dark brown.

Notice the slight ripple in the water's surface. It's a small detail, but easily accomplished by painting on a thin layer of gloss medium on top of a casting medium like Enviro-tex (after it cures) and stippling with a stiff bristled artist's brush. Leave it alone and it will settled slightly giving the water that hint of a breeze . The gloss medium is easier to control than the casting medium for fine water movement details. The pour-able waters tend to flatten out to an almost glass smooth finish, unless you pick at them for hours well into the curing stage. Using the gloss medium on top of the pour able water is getting the best out of two techniques.