Starting the south side ramp

As I prepared to start work on the south side bridge ramp I first had a major design issue to solve. To wit: I didn't know where to place the ramp and the path.

The plan drawing showed the path extending south from the bridge, curving in an "S" to carry to the steps at the front of the porch. The intent was for the path slope to be gentle, avoiding the need for steps.

On paper this looked like a good design, and before I began the bridge I verified that the slope would work based on the height to be gained and the distance of the path. However, as the bridge took shape I could start to visualize the plan in the actual setting in 3D, and concerns set in.

The problem was that in order to acheive the gentle slope most of the path would need to be elevated -- some parts over 3' above ground. Now, a short bit of elevated path is a nice feature -- but normally you want the plant and trains no lower than foot level, and in many cases ideally raised above the pathway. A long stretch of elevated pathway would be opposite that ideal -- making the garden seem distant from the viewer. In addition, it would visually bisect the garden and make it more difficult to construct intersecting paths. In short, the plan just wasn't going to work.

One alternative was to keep the path location as planned but have it follow ground contours. But this required introducing steps, something I wanted to avoid. Not so much for handicapped access but rather for ease of snow removal. (3 foot snowstorms aren't common here, but they aren't rare either.)

I started thinking about this problem before the north ramp was even started, so eventually I came to a solution. The south ramp would be shorted by curving it to the right, where there is a rock wall. The ramp would end at the top of the "cliff" and the path would continue to the north side of the porch. This preserved the concept of a gently sloping path to the porch. However, in order to provide access to the main garden south of the stream, a stairway would be added down from the ramp.

This is hard to visualize with just words, so here is a picture of the full bridge including ramp on Sept. 27 after the main structure was complete, but before railings and side trim were added:



In this picture you can see how the ramp curves towards the rock wall to the left, where it transitions to a ground pathway. You can also see the staircase that allows people to access the ground level paths on the south side of the stream.

Before I settled on the plan above I consulted with my wife, and she agreed. Then construction planning began. I was quickly clear that this section was going to be quite a bit more involved than the first two.

Construction started on September 10. The first step was to plot out the ramp. I used my trusty can of cheap spray paint, two tape measures and the 6' level (to verify that the slope wouldn't be too steep). The bridge itself is slightly wider than 3', and I decided I wanted the path to be closer to 4' wide, as it is on the north side. So I marked the exact location where I expected the ramp to end on top of the rock wall, then marked an approximate path the ramp should follow from bridge to the wall. Then I identified the location alongside the ramp that would serve as the top of the staircase. Together these markings defined the rough boundaries of the south ramp.

Then I marked the locations of the post footings. It seemed logical to have two footings at either side of the top of the staircase, and two under the ramp just next to the rock wall. Once those four were marked only one more footing was needed (assuming a maximum span between posts of 5') and that was along the side the path opposite the stairs.

Once marked, the next question was what to use for footings. On the main bridge I used 3.5' deep concrete pilings, required due to the 9' bridge span. I preferred to avoid having to dig and install 5 more such pilings due to the time required. On the north ramp I'd used precast concrete piers, each placed on a bed of mixed concrete, and that had worked very well. I preferred to use that method for the south ramp, but I was concerned that this would not be sufficiently stable given the height of the south ramp -- just over 3' from the ground at the highest point.

Fortunately, the company who makes the precast piers has a web site where they say that heights above 30" are feasible if you install diagonal braces between the posts. I wasn't sure if such braces would be required given the construction I planned -- which would provide extensive diagonal bracing as a side effect -- but this did confirm I could proceed with using precast piers now, and add bracing later as needed.

As with the north ramp I used about a half bag (30 lbs.) of mixed concrete under each pre-cast footing. I also leveled each pier in both directions and made sure the slots lined up between pairs of piers.

For the wooden posts and the beams I bought a bunch of brown 4x6x8 landscape timber. These are super strong and highly resistant to rot. They were also on sale at Lowe's for $11/per -- a savings of $6/per. Unlike finished lumber their dimensions varied quite a bit. For example, the second dimension varied from 5 7/8" to 7" in the boards I got, but fortunately was mostly 6" exactly.

Each precast pier has a 1 5/8" deep slot for a 3.5x3.5" post as well as two 1 5/8" wide crossing slots for 2x lumber on its side. Here is picture that shows how I set the 4x6 posts onto each pier:



The post sits flush on the top of the precast pier. In the slots are sections of pressure-treated (p.t.) lumber cut to fit exactly. You can't see it, but the p.t. sections are attached to the bottom of the posts using galvanized nails prior to putting the post in place. This method results in some wobbling, but it distributes the weight evenly across the pier. The wobbling goes away after the beams are connected.

For my first post I tried an alternative method. I cut the end of the post to fit into the 3.5" x 3.5" post slot in the pier. It worked, but I added p.t. slot sections to that post for additional stability, then decided to simply use the p.t. slot method described above for the remaining posts.

The first two posts I built were for the top of the stairway and thus were easy to size. I set their height to be 1/2" higher than the south end of the bridge (taking into account the expected ramp slope), and made sure they were level with each other. But the next three posts were a challenge because their tops had to be sloped to match the expected slope of the ramp. This picture shows one of the sloped posts after the beams were attached:



In the above picture there is a gap between the beams at the top. This was due to the way the beams were cut, but it gives a false illusion that the two beams were on different slopes -- in fact their slopes are close to identical.

The first challenge was determining the precise slope at the top of the beam. I used a stake to mark the top of where I expected the ramp to be at the top of the wall. I then positioned a straight 12' board, on it's side, between that stake and the top of the stairway post to define the slope. Measured, marked, re-measured a few times, cut, and voila -- it actually worked. That slope was used for the last two posts as well.

Alas, I got the height wrong. For the first post I forgot that there had to be a beam between the post and the planks. Sigh. Fortunately the error was that it was too long. Since the slope was already defined I was able to easily slice the extra 6" off using the table saw and fence. Did a similar thing with the next post when I measured from the top of the level instead of the bottom, but again the table saw solved it quickly.

I mention this because when I'm working on a substructure -- or any project where any single missed measurement will negatively affect the whole thing -- I measure and check frequently to catch errors, and recommend the same to my kids.

With the posts in place there was one more thing to do before installing the beams. There needed to be some sort of beam support on the top of the wall. This picture shows the eventual solution:



I learned from the south side ramp that the transition from the redwood bridge to the clay pathway is a bit tricky. You really want the beams that support the planks to extend as close as possible -- within a couple inches -- to the transition point to provide sufficient support. However, while the clay pathway sits right atop the ground, the support for the planks (beam + pier) is over 12" under the planks, so this requires an immediate transition from ground level pathway to a foot deep under the planks.

For the north ramp this was made more tricky because the end of the ramp was to be very near the rock wall -- a 4 foot high rock wall that kept in place the dirt near the house foundation. I was hesistant to dig too deeply into the ground for fear it would weaken the wall.

In the end I decided to support the beams, which are landscape timber and thus okay for ground contact, with a 6x6 post of landscape timber set into the ground. I fortunatly had a 6x6x8 post already (I'd bought a green 6x6x8 for the main bridge posts before I discovered that Lowe's had brown landscape timbers, which look much better). I cut the 6x6x8 timber into two equal 4' lengths (using a chain saw -- a precise cut was not needed) and used one here at the top of the ramp and the other at the bottom of the bridge stairs.

This part of the project was not difficult logistically, but did require a fair bit of labor. It was easy to identify with stakes the exact location where I expected the beams to end. I marked the spot, measured a space for the 6x6 timber, plus a little space around it, and dug using the pick and shovel. I also had to remove dirt to make room for the beams and to remove the top level of rocks on the wall. Once it was dug out it was a matter of trial and error with progressively smaller adjustments until the timber was in place at the right height, with the correct slope towards the ramp and level from one side to the other. I then filled in the dirt around it and tamped everything down with the tamping tool.

The photo above shows the green timber after it was buried in place and beams added. You can see that I also added some slightly trimmed down 4x6 timber pieces on top of the timber between the beams -- anchored with 16d nails -- to hold the dirt in place.

The end result is that the wall is now more stable than before, The actual rock wall is shorter -- maybe 3' tall. The landscape timber and the other timbers serve to make the dirt behind the wall more stable. In addition, the beams will come to within 2" of the clay pathway edging, meaning the last plank on the beam will be fully supported.

That takes me up to the point where I was ready to add the beams, which will be the first topic of the next post.

What I did last summer (part 6): the north side ramp

I'm still not sure what inspired the goal of having a step-free ramp for a walkway from the driveway to front door. Certainly one influencing factor was that the walkway we inherited had very long and uneven distances between risers, forcing you to have to take awkward half-steps on the way up or down. Or maybe it was when the kids asked if they could ride their bikes on it.

In any event, it seemed like a good idea, and if ever we need to host someone in a wheelchair we'll be in good stead after this is done.

My original concept was that we'd put in brick pavers for the start of the walkway where it meets the driveway, then transition to a redwood boardwalk at some point. Then while looking for something else at the rock/sand yard I saw some "red breeze" path cover on display. This is basically a mix of red clay and gravel that makes for a nice informal pathway. The kids loved it -- and when I priced it out ($$cheap$$) and saw how much easier it would be to install than brick pavers, I did too. Given the low cost it's also practical to try it now then replace later -- or even put thin pavers on top of it as once it settles it can serve as the sand basis that you are supposed to put underneath pavers.

Fortunately, my wife also loved it when she saw it. So, next up was to find a material for edging the path. Another fortunate stroke is that my neighbor used the composite material that is highly-touted by Home Depot on his path last year and it was horrible. He and I ended up both selecting a metal border that is on the pricey side -- about $1.70 per linear foot -- but very sold and easy to use.

So, got the edging material, and picked up the old can of spray paint tape measure and plotted out where the path would go. This is where all those years laying N scale track actually proved useful. When you lay track you have to plot out tangents, curves, and spiral easements. I did the same here, and didn't hesistate to make approximations because I'm used to doing it. I wanted the path to be 4' wide, but settled for slightly more when it all got plotted out. Then spent some time getting familiar with the edging material. I took September 2 off from work to work on this and other things, and this photo shows progress at mid day:



Ok, so the basic shape of the walkway was there, but where exactly should I place the transition from clay walkway to boardwalk? I realized that within a space of 4-6 feet the transition could go anywhere, so I chose a spot that would allow me to bend the edging and use a continuous series of 3 10 ft. edging pieces without having to do any cutting. Then I hammered them in, adjusted, rehammered, etc., until everything looked in order. This photo shows the result later that day, after I started the digging process to make room for the boardwalk:



You can see that I'd been tossing the dirt from the digging into the red clay path area. This is because the edging is 4" tall and I wanted to have 2" of tamped down dirt covered by 2" of clay, so needed to move some dirt over.

At the time I took that picture I was thinking "man, this digging is going to take forever" because the soil was hard (no rain for a few weeks) and the digging tools I had were just taking a long time to loosen it. Then I remembered I had a large pickaxe that I'd used only for things like narrow ditches. It did quick work of loosening the remaining dirt so that I had sufficient space to put in the concrete footings for the boardwalk ramp.

For the footings I used pre-cast concrete which in theory does not need any poured concrete around it. But also in theory it's not to be used on slopes. So I got a couple bags of concrete and used that as the base on which the concrete footings were set. One pair of footings was just over 7' from the north end of the bridge -- I planned to use 2x8 lumber for the beams from those footings to the north end piers. The other footings would be roughly 4-5' further down the path (not exact because the path was curving) and about 1' from the transition point with the clay path. For that section 2x6 lumber would be used because the support area was shorter. In reality 2x6 would probably have been fine for all of it, but i was being extra cautious.

I tried to get the footings to be set in such a way that they were level from side to side but matched the slope of the ramp going lengthwise along the path. The side-to-side is easy because you just use a level, but matching slope is much harder without advanced surveyor equipment (see earlier comment about being a cheapskate sometimes) so I did my best and came with a half inch, which could be addressed with shims. By September 5th the substructure was taking form:



Some things to look for: First, the cast footings are sitting on mounds of dry concrete, although it may look like dirt in the picture. This results in a very solid platform and distributes the weight nicely, making it unlikely it will settle. The dirt underneath was not loose, and had been tamped down just in case before hand. Second, you see the pressure-treated (p.t.) fir beams in place on the footings, with metal tie connectors holding all in place. This too was very solid and did not move much even when shaken. The weak point was at the transition with the clay path. I put a board of 2x8 p.t. to keep the dirt wall from eroding (you can see that by the green edging at the bottom of the photo) and held up with metal spikes that were pounded into place. This is fine for that purpose, but not fine for providing beam support. However, as I had no other option I rested the end of the beams on that board, using shims screwed into place to assure they stayed there. I suspect this will create a maintenance issue in a few years as the board shifts or erodes. Oh well, it does work and we can't see the problem externally now.

Shortly after that the rest of the substructure was ready, with the middle joist in place to support the middle of the redwood planks:



You can't really see it here, but by this time my son had tamped down the dirt in the clay path area to be 2" across and solid. This helped the next morning, as I started the day by first putting in fabric cloth, using fabric cloth staples, over the dirt in the area of the clay path. The fabric cloth keeps things orderly and separate, and also keeps weeds from growing up while still allowing water to trickle through.

Then, same day (September 7, Labor Day) I put the planks down. The ends of the planks were only in approximate location as I intended to cut those to shape after the boards were in place. You can see in this photo the planks in place and also some of the black fabric cloth below:



A couple points to note on the above. First, the place where the redwood touches the edging was a royal pain to cut. The edging at that point is an irregular curved shape, not amenable to tracing on the wood (although I tried at first) and I ruined one plank learning the process. I eventually used a pencil-compass, with a fixed length, to draw the correct line and saw it into place.

I also was forced to deal with the reality that I have two bad jigsaws. One I bought new, let a neighbor use it before I did, then by the time I used it realized the blade never went straight. I don't know if the neighbor did it or it came that way. It's Black and Decker, a brand I've not had good luck with on any tools in the past few years. The other was a Rigid, which has a great rep, but I got it from a reconditioned parts store in Castle Rock, CO, and it too never has been able to keep the blade straight. Sigh. Both of them caused problems cutting this plank and I finally resorted to a manual saw. I've had two great Bosch jigsaws in the past -- one was 220V and I had to sell it when I left Germany, the other burned out after over 10 years use in California. However -- kudos to my Dad, who sometimes reads this -- for semi-permanently loaning me his jigsaw after I complained about this to him. His is just outstanding. I have two lousy jigsaws available now to sell very cheaply.

My second point was that I struggled with how to cut the planks to accomodate the curve. Yes, I once was a math major, but shockingly the last college math course I took was over a quarter century ago. I can get by with geometry, but no matter how much I measured and drew I wasn't happy with the answers. Eventually I used a table saw (which I got for my birthday -- thanks Ann and Dad) to cut the planks seen above, then alternated between normal planks and trimmed planks. It seems to work, no one complains about the looks or even seems to notice, but aesthetically I think I'd have liked it better if the planks around the curve were all of the same size/shape. I will be using that approach on the south ramp.

Later that same day I started trimming the edges, but didn't really complete until the next day, as shown here:



All in all the north ramp has worked out. I do still need to add railing to the part near the bridge and I want to add 2x redwood to the side of the ramp, right underneath the planks, to improve the appearance. And of course I the red clay is needed. But everyone seems to like the overall appearance, the way the lines flow, and also the sense of how this bridge invites people into the garden and -- hopefully -- will help emphasize the garden when viewed from the bridge.

Once I finished this I had some serious design struggles for the south side. When I resolved them I realized I would need an even more challenging ramp *AND* a set of stairs. But that is for the next post.

What I did last summer (part 5): starting the footbridge

As I will describe in my future posts on the design of the outdoor layout, it was a given that there had to be a footbridge over the stream. Any garden railway needs paths to access the various parts of the railway, and as this is the front yard we also need a path to get from the driveway to the front door. The previously existing concrete path, as shown in previous posts, is now blocked by the pond. Furthermore, the new stream and pond completely bisect that lower part of the yard, so without a bridge people would need to detour a long way around to get from one side to the other.

When I drew plans for the front yard layout I put in various paths, but these were just general locations. One preference was to make a step-free path with a gentle slope from driveway to the house, over the stream, and have other paths branching off from that to the rest of the garden.

We plan a mix of different types of paths throughout the area, from simple stepping stones to formal boardwalks and possibly brick pavers. The intent is to give the garden a sense of variety and artistic interest. The main path to the house has to be walkable in all weather, which means it needs to accomodate a snow thrower and shovel, and thus it will be of the more rigid variety.

The order of construction for all these items was also pretty much a given. The pond/stream needed to be first, as building a stream under an existing bridge is harder. The bridge/path comes next so that people can now access the front of the house again easily. Then comes any major structures, such as a planned gazebo. After that we'll fill in with the track patterns, other paths, planters, town areas, etc.

So, with the waterfall running I started work on the bridge, knowing that I'd be tuning the water feature (last post) in parallel. The water began running on Friday, August 21. That weekend I put in the concrete footings. By the next Saturday, August 29, I had the basic substructure in place:



In between August 21 and 29 there was a mixture of planning and building. First, I had to locate the exact site of the bridge. I'll cover this in the future design post. Then I had to think about the bridge span (length between the supporting posts on either side of the stream) and the height. My early thoughts had assumed a relatively low, short bridge, but as I looked at the scene I felt that this would be way too much of a view block of the stream. Perhaps this was because the stream was modeled to be an F scale river, so every foot was carefully planned. Perhaps if I'd just built a standard stream with river rocks I wouldn't have cared if you couldn't see a few feet of any one section as they all looked the same. In addition a low-level bridge would have ruined the visual illusion of any people/building/animal scenes we model on or next to the stream.

So I decided to set the bridge posts back a few feet, and this meant a span of about 9 feet. That in turn, per all my books on deck building, mandated deep concrete footings that extend below the frost line.

I had never done anything related to a frost line before, so searched around on our county's local building code site and eventually determined that 30" is generally assumed to be the maximum frost line for most of the county, except the high elevations in the mountains. I asked around at the building stores and they seemed to agree with this. So I bought 4 10" diameter concrete tube forms which are 4' long and cut them to 3.5' to give me an extra foot as buffer from the frost line. Then bought 16 4' long rebar bars and a pile of concrete bags and went to work.

Ideally you'd rent a trailer auger to dig each hole quickly. I didn't, mostly because I'm often a cheapskate (it's usually not considered worth it for only 4 holes) but also because it would have been very hard to get such a heavy piece of equipment into place on the south side of the stream. I have all the normal fencepost digging tools, but it still took 90 minutes for each hole to site it, dig it out, then install the tube and tap in the rebar. Actually, about 80 minutes of that was just the digging. As the whole gets deeper you can remove only a little dirt at a time. In the process I learned that the frost line, which can be seen by looking at the soil profile, is only about 22-24" in our front yard. We're on the high side for this county (7400 ft elevation) so I have to guess that the 30" frost line guideline already has a safety measure factored in.

Then came the concrete. All this had happened in one day and I was tired and the light was falling fast. I didn't know what to expect -- I'd never mixed concrete before but I had mixed 36 60-pound bags of mortar for the water feature and I knew that took a lot of time. I was thrilled to discover that concrete mixing was 10x faster, or more, than mortar -- that it took longer to measure the water required than to actually mix the bag. So that went fast. I added and leveled a metal 6x6 post holder into the top of each concrete footing, and that part of the project was done.

For posts I picked 6x6 brown landscape timbers. They have the advantages of size and strength, and are designed for ground contact so they are extra-resistant to decay. Traditionally these are available only in a sick chemical green color, but recently a brown version has been produced, usually costing only $17 or so instead of $16 for a green 6x6x8. The only problem is that these are at least 6" wide, whereas the metal post fittings are designed for a "nominal" 6x6, which is really only 5.5" wide. I addressed this by sawing a slot in the post on one side so it can slide onto the metal post fitting. Then used lag screws and deck screws to hold the thing into place. I was a bit disappointed that the posts wobbled a bit -- if I do this again I'll use the 18" deep "retrofit" metal post holders instead -- but that is apparently to be expected. Once the whole bridge was anchored and braced the wobble was gone.

For the bridge path substructure I relied on a bunch of 2x8 lumber. For beams crossing a 9' span they typically recommend 2x10 or evey 2x12, however the books all say 4x8 can work too. I chose the 2x8 because I wanted to keep the height of the substructure as thin as possible -- I wanted the top of the bridge to be as low as possible, to minimize the distance a person had to climb to get there, but keep the underside of the bridge as high as possible to minimize the view blocking. I couldn't find 4x8, but for each side I put together 2 2x8 planks of pressure treated (p.t.) fir then added a third redwood 2x8 to the outside. The redwood isn't as strong as p.t. fir, but it looks tons better. The redwood almost certainly isn't needed for strength, but it doesn't hurt. Each 3x2x8 beam was attached to the top of posts on each side of the stream. Then a pair of 2x8s were used as a cross-beam between each pair of posts.

Finally, a single 2x8 was extended down the center of the bridge, between the cross-beams, to serve as a joist. The bridge is about 38" wide, meaning the gap between beams is about 29" -- much too far a distance to cover with 2x6 redwood planks without expecting serious bending or even breakage. From my 1995 deck building experience I learned that an 18" joist separation is ideal for 2x6 redwood planking. Much wider leads to plank bending, but less than 18" doesn't provide any benefit.

On Saturday, August 29 my last task of the day was staining the redwood. I've found that I like to pre-stain it before putting it on the deck because that way I get one coat of stain on the sides before installation. The next day I cut the planks to size and my daughter Emma helped attach them:



I added a second coat of stain, and except for railing the central part of the bridge was finished. The kids loved this additional novelty to the front yard ... a few days later my wife took this *non-posed* picture of them sitting together watching the stream:



With that done I began immediately working on the ramp from the north side of the bridge to the driveway. I'd done deck work before, but never with a sloped surface. As usual, I had my doubts mid-way through the project but the results turned out well. I'll cover that in the next post.

What I did last summer (part 4): tuning the water feature

So the water was running, and everyone loved the novelty. The kids would sit out near the water feature and do school work or just play with the dogs. We added sand and gravel to the stream and watched the moving water make natural formations, such as the delta at the end of the stream. The addition of the loose sand/gravel made the stream and pond bed look natural. Meanwhile, as the sand settled it covered the bottom of the pond evenly, hiding the charcoal-covered pond bed and making it look naturally sandy.

However, the water was silty. After a day the water cleared up, but there was a silt film on the top of the pond. At the time I thought it might be something that came off the mortar -- my worst fear was that the stream was eroding the mortar. I would eventually learn that this silt was due to the sand.

On the 4th day the pump conked out. I was coincidentally outside at the time. Suddenly the waterfall stopped and water began gushing from the pump in the pond. I unplugged it and found that the plastic pump casing had broken. The casing was in two parts, held together by rigid slots that had simply broken off. I tried tying them together and restarting the pump, but at that point the motor failed to restart.

I figured the motor was probably stopped due to an internal circuit breaker (I checked the CGFI breaker on the outside outlet and the panel breaker but neither had tripped). However, I also figured it wasn't worth it to investigate as the broken casing meant I would have to take the pump back. I felt a little guilty, but I did re-read the instructions, which were very spartan, to verify that there was no warning about silty water. Lowe's refunded the whole amount.

So, back I went to the pond specialty store. I told her the problem and she assured me that the Aquascape pumps could handle the silt. She also suggested a MicroSkim to house the pump, which I bought for $280+tax. (Note: I earlier said I could not find anyone on-line who discounted Aquascape items -- today I found several sites that discount them by 15% or so. I suspect that my earlier searches were too general. Today I was searching on very precise product names. Something to pay attention to going forward.)

I had to wait 4 days before the 4000 gph Aquascape pump was available. During that time the water level in the pond was stable, indicating the liner was not leaking. however, we did lose water when the waterfall was running. Almost certainly this is due to evaporation, as the area around the waterfall is perpetually wet due to splashing. Per the literature, you can create a waterfall in a way to minimize splashing, and I'll try to do that next year when I build the rock wall at the waterfall itself.

The MicroSkim is designed to sit beside the pond, in a dugout area that may be lower than the pond depth. For now I've just put it in the center of the pond, where the box opening is really to high given the water level, but I compensate by not including the skimmer door. I plan to create a permanent dugout for the MicroSkim before this year is over on the south side of the pond.

Here is a picture of the pond on August 30, 9 days after we first turned on the water and 1 day after the new pump and MicroSkim were in place:



The black MicroSkim box sits rather obtrusively in the pond center, but it certainly works. The water at this point is now clear except for a small patch of floating silt in the center, and that would clear up before day end. I learned that I could get rid of the silt by spraying off the biofilter pads and by using a pool net to scoop it out of the pond. Once the silt was removed it doesn't come back unless you add more sand, which we have stopped doing now that we seem to have enough.

You're not supposed to spray off the biofilter pads more than once per year because you want the beneficial, algae-eating bacteria to stay on the pads. However, if you are just starting the pond spraying them off a few times to get rid of the initial silt doesn't hurt.

You can see what the pond floor looks like in the picture above, covered by sand and lose gravel. Frankly, its appearance is better than I'd hoped. Next are two pictures of the stream bed. Some of these show the under-construction footbridge and a timber that I put across the stream to aide the construction process -- I'll address that construction in the next post.





Near the top of the picture above there is a section of stream that I rebuilt during the pump outage. Some of the embedded rocks and some mortar chunks came off in a few sections where I didn't do a good job making sure the mortar was thick enough and compacted enough. One spot was right over a lining joint, and the caulking was showing through. In addition, that area of the stream was not as aesthetically appealing because the water simply rushed down a steep slope instead of meandering, and the slope was too steep to allow any loose gravel to stay put. So, I solved it all by adding a pile of concrete, not mortar, on top of it to reform that part of the stream into a "step" for the water to run over.

The concrete was something I had bought as part of building the bridge footings, and I discovered to my joy that it mixed in about 1/10th the time as mortar does. I also found, to my near horror, that the cement dye created a very different color in concrete than it does in mortar -- instead of a rusty-brown it was closer to a sharp blood red. However by covering the new concrete patch with lots of embedded stones, supplemented by loose stones, it now looks pretty cool and adds interest to the overall stream flow.

Right now the pond and waterfall are stable. I need to add water every day or two due to evaporation, because if the pond level gets too low not enough water will get into the MicroSkim for the pump. This maintenance will get easier once I get the MicroSkim into it's permanent place, because the MicroSkim door allows for more variation in pond levels. I also need to clean the debris out of the box approximately weekly.

In addition, we had one major rain storm and I found I had to syphon water out of the pond during the rainstorm to prevent a spillover and possible erosion. The MicroSkim has an outlet for overflows, so that will be automatically taken care of once it is in its permanent dugout.

We've just run into a very cold spell now, with night temps going down to freezing, so have shut off the pump. We're expecting warm weather again soon, but by end of October I plan to shut down the pump and drain the pond with a syphon until next year.

My next post will discuss the footbridge and path, which I've been working on for about a month now.

What I did last summer (part 3): plumbing the water feature

The previous post described the building of the water feature but only briefly touched on the plumbing necessary to get it working. In this post I'll talk about the water feature plumbing in detail. In the next post I'll talk about the many adjustments made after we got the water running, and the related lessons learned.

As a complete newbie to the topic of garden water features I found the jumble of information about water feature plumbing very confusing. I read the literature that I mentioned previously, and talked to a lot of pond/stream owners at the 2009 Garden Railway Convention (which this year was in Colorado). Eventually I sorted out the information as follows. First, there are basically three kinds of water features: only pond; pond + stream/waterfall; and only stream/waterfall. The type you choose will determine what plumbing you need -- and some of the things you see advertised won't apply to your type of water feature.

Second, if you will have a pond you need to determine up front if you want fish and/or plants in your pond, and if you want fish do you want koi, which are more complicated to take care of. The more life you want in your pond, the more plumbing support that is required.

So, I made some decisions to help simplify the process. First, we won't have koi, as they require a deeper pond (preferrably 3 feet deep) and my pond will be only a foot deep at the maximum. Goldfish are cheaper and easier from a maintenance perspective. Second, yes we may add fish and plants in the future, but first we'll run the pond for the rest of this year without them just for the experience and to let the new mortar, etc. properly cure, as mortar and cement can apparently release chemicals that harm water life.

With that decided the plumbing requirements were somewhat simplified. First, you need to have a pump to move water from the pond to the top of the waterfall. More on that in a bit. Second, you need to protect the pump from water debris and to have some means to remove that water debris. Third, you need some kind of filter for the dirt, dust, and algae. Various things are suggested in the literature, but the biofilter concept seems the most popular. If you want fish you may have to add other mechanisms, such as UV filters, to keep the water habitable, and you'll need to monitor water chemical levels regularly, just like with a fish tank. For this year I'm not worried about any fish-related requirements, but I'll probably have to learn more about those next year.

As mentioned in the last post, Aquascape has a line of products that they sell through pond specialty stores which are perfect for the task, but extremely pricey. For about $1100 you can get a do-it-yourself kit that includes everything you need for a small pond and waterfall, although I'm told most people pay another $200 or so to upgrade the pump for more water flow. When you get one of these items like, say, the "MicroFalls", you'll pay $280 list (and I've not found any one on-line who discounts these products) and the components look like something you'd pay less than $50 for at a big box store. Alas, the big box store doesn't have anything close to an equivalent, although you could probably build something functionally similar from parts if you knew what to build and what parts to acquire and customize.

So, in the end the Aquascape do-it-yourself kit is probably a smart purchase for a lot of people in that it gets you where you want to go with minimal aggravation. At this point I own most of the items in that kit, although I took a long road to get there (some of those details will be covered in the next post).

Two things I knew I wanted were a biofilter and something that would serve as the start of the top of the waterfall. The MicroFalls is both, and was recommended in those Jack Verducci Garden Railways articles I referred to earlier. So I bought one and installed it at the top of the waterfall. This picture shows the box after it had been put in place but before leveling and attaching the hose:




This next picture shows the MicroFalls from the side, fully installed:



Installation was not hard, although the directions could be simpler. Dig a hole until the lip (water exit) of the MicroFalls is at the level you want. Then attach the hose to the lower back of the box (this probably means digging a narrow ditch for the hose, which I did), and attach a rubber liner to the front lip using the instructions. Put in the two biofilter mesh pieces, then add some lava rocks to the rock net-bag on top. At that point you're ready to have a pump push water in through the bottom hose. The water will percolate up through the filters and out the front lip. The beneficial bacteria that will clean the water will form naturally, but just in case Aquascapes has a small can of dry bacteria for $20 that you can add to your pond to speed the process along. Don't fill in the dirt around the box until you've verified that there are no leaks.

Next on my list was a pump. Pumps can be submersable or external, but most people use submersible because they are easy to locate in the pond and by doing so you deaden the pump noise. These are rated in gallons per hour (gph) and also in watts of electricity drawn. The gph rating is complicated because the official rating is measured assuming the water is pumped out directly and not moved anywhere. Vertical movement, like up a falls, cuts down on the gph tremendously, and horizontal distances also cut down, but by a factor about 1/10th of the horizontal. There are charts in books that show the degradation on gph for your given situation, but those are only estimates as different motors have different characteristics.

Finally, once you've figured all the math out you realize, if you are a newbie, that you really haven't a clue what your output gph should be for the size of stream you want. You can guess, but you don't really know.

In the end I bought a "cheap" 3600 gph, 300 watt pump at Lowe's for $200 + tax. It was the biggest they sell. The equivalent Aquascape is over twice that price.

Unfortunately, the pump didn't have a provision for a debris filter. After thinking and thinking about how to keep debris away from the pump I took a short cut and bought a $30 "pump buddy" from Aquascape that is simply a filter bag that wraps around a pump.

Then I bought two 20 foot lengths of flexible 1.5" tubing (that was the longest size our local Home Depot had) and some connectors. I connected the pump and the tubing up to the Microfalls and all was ready. This next picture shows the pump, wrapped in the "Pump Buddy" and sitting in the dry pond, and the tube leading from it to the (off camera) MicroFalls:



All was ready to start the water running. As I said earlier, this was an exciting day given how long we'd been working on this. We put a hose to the top of the stream and turned the water on:



The water began trickling down:



And down:



To the island:



And to the pond:



Yes there were a lot of photos taken that day. And video too. When the water was deep enough we turned on the pump and the MicroFalls started gushing, as shown in the last photo of the previous post. This photo shows the pond filling up after the pump was turned on:



All was well, except that the pond water seemed murky. As it turned out this would create a plumbing problem, but I'll cover that in the next post on tuning the water feature.

What I did last summer (part 2): getting the water feature running

After digging the stream and pond bed, and verifying that the bed and walls are level and/or sloped as desired, the next step is to add a liner. The purpose of the liner is to keep the water inside the feature, and probably the biggest problem a water feature can have is a liner leak.

There are rigid liners -- which have shapes already built in -- and flexible ones. Within each category there are many choices and the Water Gardens book I mentioned previously does a good job comparing the options. For me, a flexible liner was a given as this is a custom shape (the pond may look circular from a distance, but it intentionally has a slightly irregular shape to make it look more natural). And I was ready to invest in the best quality as I wanted a liner that will last as long as possible -- 30+ years ideally.

This meant a rubber liner with underlayment fabric to prevent possible tears from rocks or roots underneath. You won't get this material at the big box home improvement stores in my area, and the pond specialty stores provide it at a steep price. I found it for a decent price at a local rock/sand yard. This next photo shows Emma and Daniel posing after the underlayment was in place (they helped with that project):



The rubber liner was one of those projects where you have to do it first before you really know what to do. It sounds simple enough in concept. But the books talk about knowing where to fold over the liner and about splicing two pieces together. The splices are especially tricky because even with the recommended splicing tape there is a big risk of leaks. Jack also talks about using rubber material where the manufacturer adviced against cutting it. That wasn't the case with the material I had, but that was something I had to figure out on my own.

We started at the pond and worked our way upstream with the rubber. One mistake I made was to undersize the rubber liner piece for the pond, necessitating a splice under the pond itself (which I'd hoped to avoid -- intending instead to have splices only under the moving stream water). I was trying to save money when I bought the rubber liner sections so stuck to the narrowest pieces available -- 10' -- in retrospect it would have been better to buy the 15' sections and accept that there was going to be some wastage.

We spliced the liner in place. If I was to do it again I'd choose a level surface, then move the liner over to the water feature. I bought mineral spirits, as recommended in the instructions, for cleaning the liner surface and applied the splicing tape as described. It worked, except where the irregularities of the ground surface caused the liner to bend up, and in those cases it appeared that the splices had gaps (this is why I would have used the level surface first). After trying a number of things I filled the apparent gaps with caulk ("Polyseamseal") and relied on the weight of the covering material to keep the whole splice closed. I know know that this works -- our water feature has been confirmed not to leak -- at least the pond itself. But at the time we were simply operating on faith.

With the liner in place the next step was to add the surface material. Jack Verducci, as noted in the previous post, recommended a mixture made up primarily of ready-mix mortar, plus doses of portland cement, fire clay, and dehydrated lime. He said the resulting material was easy to work with, allowed you to shape the pond surface, and allowed you to fix pond and stream rocks in place. He also noted that you could choose the color of the mixture with cement dye.

My first problem was finding the materials. Mortar and portland cement are available at any big box home improvement store. Dehydrated lime was hard to find, but I did eventually locate a single old bag of it at a local garden store. I never found fire clay as a product, although it's all over my geological maps of the Rockies. Maybe this is a product that garden stores have in Jack's area, northern California.

The next issue was that with all my home improvement stuff over the years I'd managed to avoid any cement or mortar work except fence post concrete. I thought about renting a cement mixer, but was told that I really needed a mortar mixer, and those are hard to find. (I later learned that mortar is much thinker and harder to mix than cement, hence the need for a special item.) However, I was told you can buy a hard plastic mixing trough for about $11 and mix with a hoe, which is what I did.

Now, the Water Gardens book mentioned use of cement or mortar as a possible filling for a garden pond, but more as an aside not as a recommended practice. They also suggested pouring the mixture over chicken wire, placed over the liner, to add strength. I didn't do this as I was following Jack's method, however now that I've seen the results I might try that suggestion for my next water feature.

So, I started at the bottom of the pond, figuring that any mistakes made in appearance could be more easily corrected there even after the rest was done. This is one of those "contingency steps" I talked about in the last post. My first batch was only mortar with portland cement, using a "charcoal" colored cement dye. This seemed to go okay. I'd bought a variety of mortar shaping tools and quickly learned which ones I liked the best. After it dried I found that the dark color of the mixture turned very light, making me wonder what use the dye was. I learned that if the mixture was put on too thin it would tend to easily crumble under weight, so 1" thick was the minimum I used after that.

I added lime to the next batch and it made the whole thing crumbly and barely useable. I haven't reused lime since. Probably the lack of fire clay means that lime isn't an option. The next two batches were just with portland cement added to mortar, and I tried different things with dye, but it still usually dried very light. Then I found, during a rain storm, that when wet the mixture returned to the died color. Interesting.

Next I tried a batch of mortar only, no portland cement, and this seemed the easiest to work with so I stuck with that method moving forward. As I got near the stream bed I changed dye color, to try to match the natural area I was trying to model. This was a mix of "Buff" and Terra Cotta", which resulted in a reddish brown. I also added a bit of sand to the surface while the mortar was dry and a few stones to see how they held up. This picture, taken on August 9, shows the mortar work to that point. It also shows the rubber liner in place, and the splice seams are evident:



I have to admit that up until the stream I was really doubting the whole method that I was employing. However, the stream started working out. I figured I plow on upstream, and would address the pond bed later if needed. As it turned out, the pond bed came out just fine, but that's a later topic.

Moving to the stream bed meant moving to modeling, artistic phase. I spent some time looking at on line photos of the Arkansas River in the Salida area, noting features like islands, river depth, rocks, and river sides. At this point some of our kids got involved because of the fun of modeling, notably Paige and Emma, and this photo shows them hard at work the next day:



The next day I looked at the results of our efforts after the mortar had dried. It actually looked, to my eye, pretty good. This photo shows it from above, but doesn't really do it justice:



You see the island, and if you look closely on the sides you can see a few rock-lined gullies that the kids put in -- just like on the real river where streams come down the river side. There is also an attempt to use rocks to create a natural mini-waterfall like appears in places in the Arkansas River. On this last feature, I had found a sprinkler pipe when I dug the stream bed, and I left it in "just in case" we ever wanted to use the sprinkler system again. I chose to put the liner over it and use it for this water feature.

As I looked at this I realized I had little idea how it would all look when the water was running. I toyed with the idea of running water temporarily to find out, but decided not to as I figured I could correct any problems later with more mortar or by adding loose stones and sand. It turned out that this was exactly what I would do.

By August 15 I'd gone back to the pond area and put in the walls, using the methods that I'd settled on in the stream beds, with mortar, cement dye, and putting sand on top of the mixture after the whole thing had been smoothed out. You can still see some seams in the wall between different batches of mortar -- I was getting better and hiding them but still not perfect. For the record, the walls in this photo took about 15 60-pound bags of mortar -- and another 6 or so for the thinner floor (the walls were up to 2" thick in order to provide sufficient support):



Fast forward 5 days to August 20 and the stream bed is nearly done, in this photo taken from the top of the wall that will be the source of the waterfall:



As I moved upstream the walls got higher and steeper -- a natural result of the fact that I dug the stream bed deeper upstream, and lower downstream nearer the pond. I decided this would be more like canyon walls, and that I'd first build the stream bed then come back and build the canyon walls. As I moved upstream I thought of how real rivers appear near waterfalls, and remembered that there are often large rocks at the bottom of the waterfall itself -- rocks that fall as the water erodes the waterfall wall -- then there is evidence of those rocks downstream as the move slowly, usually in floods over millenia, and get slowly smoothed out. I tried to recreate that with the rocks I used, and also increased the number of small rocks in the streambed, using rocks from backs of concrete gravel which, by luck, had the right color.

I also began collecting rocks to serve as the canyon wall. I made a couple of trips to the local rock/sand yard and found some bulk stones that fit the bill, and were very cheap because of their irregular shapes. I also found some similar rocks at a public resevoir near Leadville, on a trip we made at this time, and took those. By the next day the stream bed was complete:



The next step was getting water running. Garden Railways has run a few articles on filtering pond water, and Jack Verducci specifically mentioned a product by Aquascape that is a biofilter that sits at the top of your waterfall. The advantage of the Aquascape system is that it works. The main disadvantage is that it is very pricey, and sold only at pond specialty outlets. There is another minor disadvantage that the instructions are harder to read than they need to be, but if you get stuck the experts at the pond store can help you out.

I looked up Aquascape on line and found that a) no one discounts their stuff, but b) there is a nice store right in our little town that carries it. I went there, plunked down $299+tax, and had the waterfall biofilter box which I installed at the top of the falls (more details on that in a later post). I then got some cheap piping and connectors at Lowe's, and also got a cheap-ish pond pump there. Set it up and on August 21st we started the water running. First the garden hose was used to test the stream and start filling the pond. Then when the pond level was high enough, I started the pump. This shows the waterfall shortly after it was first started, with daughter Laura and dog Sunny looking on (this was a whole family event, pets included):



The waterfall in the photo is actually just a piece of rubber liner extending over the existing rock wall. I intend to replace that with a wall of rocks that match the color of those in the stream bed, but that's probably a project for next spring. My intent was to get the water running.

Well, it was a success. The stream looked great, and everyone loved having the water feature sounds and smells. Over the next few weeks we learned a lot about the whole water feature and made numerous adjustments as a result, which I'll cover in my next post. Simultaneously, I started work on the footbridge over the water feature, which I'll also write more about.

What I did last summer (part 1): starting the water feature

Wow. Over a month since my last post. I'm still very, very busy on the outdoor layout but haven't been posting on it. I've drafted a couple posts describing the design/prep phases of the outdoor layout, but haven't put them up yet because I haven't gotten around to scanning in maps/drawings.

So, instead of waiting for those to get ready, I'll just skip forward to NOW and show what I've been doing this summer. I'll still get to those background posts (someday), but this way I keep the blog somewhat up-to-date.

In this short series I'll be describing two projects. The first is the creation of a pond/stream/waterfall feature, which in F scale terms represents the river in the upper Arkansas River Valley. The second is the creation of a bridge/pathway that will be necessary to access and enjoy the garden railway. I'm tackling these two projects first as they railway and rest of the garden will be built around them.

For reasons that I'll describe in one of those future posts, we decided to start the outdoor layout in our front yard, and I decided that the focus of that portion of the layout would be Leadville, CO (per my previous post). This is a picture of the front yard shortly after we moved in back in late 2005:



The picture was taken from the end of the driveway. The driveway splits, going off to the right toward the garage, and to the left, where it circles back down to the street. The "front yard" is the area immediately in front of the house, bordered by the driveway.

As you can see, we're in a forest. Not all of the trees shown in that picture survive today. We took away several near the house as part of a "fire mitigation" program (we're in a "firewise community") in 2008, and also lost three big ones in the huge spring storm of April, 2006:



The original owners had set up the front yard area as a sprinkler-fed lawn supplemented with a few non-native aspens and firs, plus several rock-bordered patches where tall pine trees stood in a bed of mulch. The natural slopes were controlled in a few places with a rock walls, none taller than 4 feet.

The front yard did not keep up it's presentable appearance due to our neglect. First, we have never turned on the sprinklers, leading of course to a deterioration of the lawn. This was expected -- we always have planned to replace the lawn "someday". Second, the main concrete walkway into the house was already showing signs of erosiondue to poor installation when we bought the house, and it got steadily worse. Here is how things looked in this August 2007 photo, taken from near the porch steps:



That particular photo was taken as one of a series of "before" photos as part of my 2007 house-painting project. This next picture is an "after" photo, showing the house in the late fall of 2007:



I spent much of early 2008 on other projects, including fire mitigation work. Then, after a long time spent struggling with a design for the outdoor layout, I started work on the outdoor layout. The first project was to get rid of the eroding concrete sidewalk in the front. I started this in late 2008, and by early 2009 it looked like this:



Not a lot of progress, I know. It did take a long time with the jackhammer to break up the sidewalk, as the concrete was 12" (and more) deep, but the real problem was I was struggling with exactly how to move forward with the layout. I had a general plan then to create a pond, stream, and waterfall in the front yard. So I decided to use the pieces of broken concrete to help create the "fill" around the future pond, which explains all the white "rocks" you see in the picture above.

But I'd never built anything like a pond/stream/waterfall, so I tended to find other things to do instead of work on the outdoor layout. Alas, as the picture above shows the front yard had become quite an eyesore, so my wife said I had to do *something* about it. I agreed.

I read what I could on the topic and found two sources of information I'll recommend. One was a series of articles in Garden Railways, starting in April 2004, by Jack Verducci. Garden Railways frequently has how-to articles on water features, and I read all of them dating back to 2000, and each one was interesting. But Jack has been building garden railways and water features for a very long time and his articles provide a depth of experience not available elsewhere.

Of course, Jack's articles describe one method, his, and his focus is solely on building scenery for railways. As great as that is, I sought a more general perspective on garden water features and IMHO the best I found was carried by Lowe's: Complete Guide to Water Gardens by Kathleen Fisher. I did buy a few other books, but this one really superceded all the others.

Looking at these two sources a couple things stood out. First, as with all such projects, you can only learn so much by reading. Until you do it and get a tactile sense of the materials involved and how they go together, you can't really act with confidence. You just have to try a step, assess, and correct mistakes as you go. Sometimes you have to plod ahead hoping that end result will be fine, but not really being sure. In that case it's best to try to arrange contingencies, in case you have to do some repairs later. I'll illustrate this principle with examples as I describe my progress.

The second thing which stood out is that while the water feature industry has evolved to the point where there are standard methods for doing everything, if you want the water feature to look like a scale model you'll have to go outside those standard methods. This is where Jack's series of articles so was helpful.

So, armed with this book knowledge, I started the project for real. Well, as I noted earlier, the months of April, May and most of June were taken up with forest maintenance tasks, but by mid-June I started digging out the stream and filling in the area around the pond. I intended to follow the method Jack described, so I used his article to calculate the size of the stream I wanted, to match the width of the Arkansas River around Salida. The stream bed has to be dug wider and deeper that what you intend it to look like in order to account for the material that will be used to fill it. I started the digging process by using some cheap spray paint to identify the borders of the stream and pond, then started digging, moving the dirt via wheelbarrow from the streambed to the areas around the pond. This took a few weeks, working a few hours on most days.

This next photo is taken on July 20 of this year, and my son Daniel was busy tamping down the dirt around the pond (yes, he was paid):



I was very concerned about the idea of simply dumping dirt over those concrete blocks and trying to create a solid walking surface. I'd read in various books I have on building patios (yes I have a very large home improvement library from past projects) that you can create a solid platform using a tamping tool, then wetting the dirt and doing it again until it's solid. However, I wasn't sure this would actually work until we did it. Fortunately, the process works just fine. The next two photos show the pond and stream area after tamping and filling were done and we were ready for the next step:





In order to make the pond walls even we, of course, used our 7' level. This tool is essential for these kind of outdoor construction projects, and I frequently make use of it on the indoor railroad as well.

The only challenge was finding enough dirt for fill. The streambed provided some, but in order to get the rest I dug a "cut" near the side of the house where I will someday, hopefully next year, put in the rail line that will connect Leadville in the front yard to Salida in the back.

You'll notice in the second photo that we'd also extended the blue/red rock wall along the driveway to account for the new pond. We were able to do this because there were a lot of excess rocks available after we removed the rock borders that we won't need with the new garden design. We still have a pile of excess wall rocks that I intend to use *somewhere" before this is all done.

So that takes us to July 21. The next post will cover the building of the water feature up until the exciting day we started actually running water.