To terrace or not to terrace?

In parallel with the wastewater treatment decision, Dad is very insistent that we decide right away on the garden layout, and in particular that we put terraces in. I am less sure, not least because I'd never envisaged having terraces nor had it been something we'd discussed.

Much exchange of emails ensued... At one point I had talked myself into terracing, to the extent of having a giant HaHa... but then Dad talked me out of it again. So now we're back to square one, no decision on layout yet made and awaiting input from Michael from Septech on how detailed we need to be in specifying pipe layout.

I can't face summarising it all, so here's the email conversations recorded for posterity. ;-)

On 11th Nov Dad wrote:

I think terracing of the block is essential in order to retain water for garden beds. I believe each terrace can accommodate two rows of appropriate trees, at the high side and the low side. The stepdown of each terrace will give a place for trailing plants and for shrubs. The size of each terrace is dictated by your plans for the area other than as an effluence field. The pipes can be buried beneath the surface if it is more appropriate for the use you intend for the terrace. In fact, you may not want to put in terracing at all. But you need to take time to consider this in the light of needing to direct Michael, and when he proposes his pipes you need to accomodate these adequately. You are the one with the masterplan.

I replied:

In terms of terracing, I don't know yet. There are pros and cons. But at this stage, I don't see that whether we have terraces or whether we have the pipes simply laid on the surface with mulch would make a huge difference to the length of pipes we'd need. I will ask Michael though. For the moment I think we go with whatever layout in that specific area is the simplest for him to quote on, so we can get the plans submitted in order to get the building permit underway. If needed we can then revise the details of piping layout later as they'll remain in the same area so can't see it being a big deal

On 13th Nov Dad replied:

I suspect from your last email that you are not aware that the council health inspector will not permit us to move the field as established by the drainer before commissioning the system without another inspection. That is why I wanted you to consider the size of each of the terraces if terraces were to be used at all. Terraces make the area more efficient for use as a soakage of wastewater area. As the gradient is such that over the distance from the corner post under the master bedroom of the old house to the cornerpost under the kitchen on a diagonal is approximately 1 metre in fall. That translates to about 1m fall in approx 12 m. Since we can curve the terraces to the shape of the hill we can gain a slightly sloping open area with a width of 3m and a step down for each area of about 400mm. The 45m area available would permit 4 such terraces. The field has to be accounted for the minimum of 400m only on the parts where the pipes are going on the level along the length of the terrace. The drop down to the next terrace at either end does not apply to the overall capacity of the system to dispense water.

If you wanted to have only 2 terraces then the stepdown would be approx 1m. That may be more suitable to you. It would mean moving subsoil down to the lower area after scraping off any soil that could be used on the finished terrace. That applies to all terracing of course. The stepdown requires a slope rather than a sheer drop. This takes away from the available width of the area to accommodate the terraces, but a slope is more serviceable in the long run with less maintenance.

As long as you have a clear idea of this information you can make a considered choice about whether to have terraces or not. If you like you can simply distribute the pipes on the existing gradient. You also have the option of having the pipes buried at least 300mm under the ground or lying atop the ground with mulch atop them

I replied:

Yes, I understand we can't move the overall location of the field.. But, if the field is defined as simple a specific area - ie if you imagine we roped out a section of land between the house and the gums at top of driveway, then it may be that provided we stick to keeping the pipes within that specific area, we might have flexibility to change the precise details of pipe arrangement prior to implementation.

It all depends on how detailed Michael has to be in terms of how he describes things. Eg: if he has to describe the location of every single individual pipe and bend, then we wouldn't be able to alter a thing without having another inspection. But if all we need do for the permit is to commit to there being a set length of pipe in total and for it to be arranged over this particular plot of land (but not give details of precisely how the pipes would be arranged within the borders of that plot) then we would still have flexibility to decide the best garden (and thus pipe) layout closer to implementation.

Eg: do the pipes have to be evenly spaced within a given area, or can their arrangement be more finely targeted, so it only goes on those areas that have garden beds and not on the areas that are paths? As an illustration, see:




If we went for a garden layout sort of like this, would we be able to focus the pipes in just the dark green bedding areas? This is what I want to find out from Michael. (nb: this is just one illustration: I would want to liaise with Prue before confirming precise shapes of beds etc, just showing to you so you get the gist of what I am asking).

Of course, it would be possible to still have terracing with this sort of garden although you wouldn't want too many... But, thinking about it more, there is another reason why having at least one terrace would be good - and that is so that we could use it as a Ha-Ha.

In case you don't know what a Ha-Ha is, it is basically an invisible fence. They used them a lot in old country houses here in the UK, as a way to keep sheep and cows out of the formal garden areas without having to build an obvious wall that blocked the view from the house.

I wonder if we could do a form of this encircling at least the bottom parts of the garden which had a HaHa type cliff edge - of a sufficient height to stop sheep/cows/etc. We could use the clay that we have excavated from other areas, supplemented with lovely topsoil that we buy in for the top for planting in - to help build up the height sufficient to give a high enough edge.

This would also solve a problem I have been worried about: how to be able to have a nice garden area without sheep getting into it and having to erect yet another fence. You mentioned if we had 2 terraces the step down would be 1m. So does that mean if we had only one terrace, that the step down at the outside edge would be 2m? This would be big enough to keep out sheep wouldn't it?

What do you think?

Dad replied:

1. A metre fence with a slope to complement it will be adequate. There are not slopes that a sheep or cow will not go up for good tucker, unless we are talking a sheer wall of sleepers or rock.

2. If we have only one terrace it will make a wall about 1.6m to 2m as a rough calculation. This terrace will not be level, most likely, but have a small gradient. Before beginning any excavation I would establish the gradients required to follow by placing markers for the man on the machine, and by frequent checks of gradient points as the excavation continues.

3 .The problem with moving the pipes is that you cannot handle them unless licensed to do so. They are a health hazard as they carry black water to be treated in the ground.

4. However you go about this there is sufficient area to get 400m of pipe in for the dispersal of the water. I would imagine there are guidelines as to how close together the row can be, and this relative to the percolation value of the soil. I am sure they will have it worked out to be certain all water delivered remains under the surface and doesn't seep to the surface because of saturation of the area.

I replied:

Hi Dad,

Re: 1)

We *are* talking about a sheer wall of rock. That is what a Ha-Ha involves.

I just realised I have some photos of a real HaHa that may help explain it better. In fact this is of the oldest HaHa in the world that was installed in the late 1600's and has been keeping out sheep ever since. I saw it with Mum at the Levens Hall garden a few years ago up in Cumbria. This is me standing on the edge of the Levens Hall HaHa with my toes nearly off the edge, taking a photo of the rock retaining wall. See, it's really clever, you can hardly tell there is a wall there even when standing right above it.




And this is the photo I took, looking down. You can see they had pebbles at the bottom and rocks lining the wall side




I like the idea of a HaHa aka an invisible fence from the house side, because I really don't want to have everything looking like it is fenced in. The orchard wall was something that we were forced into and luckily you can't see the wire from the house, but it has spoiled my plans for that part of the garden... kind of hard to stroll through the trees down to the dam when you have to go through giant fencing. But hoping it will be OK in the end because we will grow things on the wall and make it look less like a prison fence encircling them. We had no choice anyway, protecting the trees was the top priority.

Re: 2)

A wall of 1.6 - 2m at it's highest point down near the driveway sounds great - although I want to discuss with Dave too. It would mean that even as we got up the hill towards the house there will still be a reasonable sized drop quite a way around. So it would only be near the house that we had to worry about having a low height fence.

We could have one small part where there were steps and a gate in the wall to allow you to walk up through the garden from the driveway.

Re: 3)

Of course I understand we can't move the pipes once they have been laid. But there is a long long time before a single pipe will go near the place. To spell it out more clearly, this is my understanding of the timing.

Dec 2008: Michael creates application including plan (to whatever level of detail is required)
Jan 2009: Dad gets building permit to start work on the old house
Sometime in 2011 or even 2012: We actually get round laying the pipes.

There is a lot of time between now and when the pipes need to be put on the ground. All I am saying is that why commit now to a detailed layout of exactly where each individual pipe will go, where it will bend, etc if we still have years to go before it will be implemented? The *only* reason to commit so early would be if the council required that level of detail for the permit, but that is for Michael to tell us.

Of course: the one thing I need to check in having just a single big terrace - which can't do until on site and can see the gradients - is whether having such a terrace would mean you couldn't see the dam from the house. I'm hoping not, am hoping that the slope is such that you would still be able to look down and see it, that the only parts that may be hidden are the driveway and part of the orchard...

Dad replied:

I did not say the wall was to be down near the driveway, but I referred to a terrace created by removing soil and subsoil layers to whatever size you wanted within the 45x45 area. The thought I had was that the terrace would ultimately regain the original level of the ground near the trees. I never thought you wanted to dig below the level of the trees to create a trench. Doing this may compromise the runoff prospect from the saturation field. You cannot go closer than the front of the house with any diggings because of the underground pipeline restrictions, so to manage a trench to runoff would have to be arranged in the other direction,across the road and thereby require a bridge of sorts.....I thought you would use the extra soil from the house excavation and from small terraces to build up a roadway between the trees. The idea of a Ha Ha for the wastewater area is going to greatly restrict the area available for pipes. I was talking about a wall or slope at the high side of the wastewater field. The vegetation of this field cannot be fruit trees or vegetables. Nothing that will be consumed. The area you have bending up towards the house is where the septic has to be put. This cannot be too far from the houses nor be too low as a very low gradient for the septic inflow pipes from bathroom and other area is required (apx 40/1 if it hasn't changed since I last laid such pipes). The tank could go under the area for the herb garden in your sketch, but must be not directly under as access needs to be readily available for service. A large terrace may require another percolation test as the test had only 600mm holes into the undisturbed terrain of the area. I think Michael's input is required before too much more detail is added to the area.

update from Dad

Dad writes to tell of his plans for later this month, focusing on watering. It is coming into the hot season there...

Email from Dad (2nd Nov)

In three weeks time I have two days together, a Sat/Sun scenario, so will go up to Amherst.

I will pump 1000gal into the tank for irrigation as a drip to all the trees over as long as it takes for the tank to empty. Each of the trees has a pipe with a valve that is a gate valve, a very important point for a drip system because the pressure does not affect the leakage from the valve as in the tapwasher type valve used in high pressure systems. I will only be watering the fruit trees in this way.

As well I will thoroughly drench the trees while there working on other tasks. I will pump water from the dam while watering full bore all the trees and only leave when all the trees are well watered, and there is a full tank for using as a slow drip to the trees in the ensuing period until I can return. I envision it would take about a month for a slowly dripping system to empty the tank. I aim to encourage the trees to seek deep water by this method, and feel the lesson learned by not watering the lemon gum trees during the drought will apply here as well. There seems to always be water deep down in the clay areas.

I will mow the olive grove and the orchard as well while there.

fake lawn becoming more popular

It seems like at last fake grass is starting to catch on in Australia - see extracts from article below.

I suspect we are going to have to go down this route at least in part so I don't go nuts from lack of greenery. Fake is better than nothing!

I reckon too it could also be a really practical lower-maintenance alternative to gravel or cobbles for the pathways between garden beds...


Extracts from "Which Grass is Greener?" (November 4, 2008)


Frustrated at seeing their once green lawns turn to parched, dusty hollows because of the watering ban, many people are weighing up the choices: is synthetic turf that you don't have to water kind to the environment or are drought tolerant grasses the way to go?

Peter Ammoun, of Lifestyle Turf, says demand has never been higher for his artificial turf, with this winter "the best ever".

"When we first started, the requests were in summer and for smaller courtyards and little shady areas," he says. "The average size was about 35 square metres, but that has doubled and people are doing their front and back gardens and around swimming pools, plus nature strips." ...


While sales of artificial turf have increased, demand for the real thing is still high, according to HG Turf's Peter van Leeuwen. He concedes that synthetic turf is more practical because there's no need for watering or mowing, but it doesn't have the same feel underfoot as natural turf, which is softer and more cooling...

"A lot of drought-hardy warm season grasses are available and, once established, require little water," van Leeuwen says. Instead, drought-tolerant, warm season grasses such as soft-leafed buffaloes are being grown including Sir Walter, sapphire and palmetto.

Kikuyu, used at Melbourne's Royal Botanic Gardens in heavy traffic areas, and couch are also viable alternatives. However, like buffalo, they brown off (already there are signs of lawns under stress after two dry months) but they bounce back after rain or being refreshed with grey water...

The cost of natural turf and its synthetic counterparts vary greatly, with real grass costing $7-$10 a square metre and artificial turf, fully installed, $80-$90 (depending on the quality and supplier). If you choose to do it yourself, the cost is about $35 a square metre.

update on trees

Dad recently did a trip up to Amherst to fix the irrigation for the new orchard trees. While there he took photos, here's a few:





In Dad's words:

These were taken when I went there to install small watering pots to the new plants, and check progress of olives. Only 3/4 of a tank of water has rained since transferring water to the large tank. I will pump the irrigation tank full next time I go and water the entire orchard. I will also install a drip attachment to all the small watering points for the orchard and allow the full tank to slowly drip into these tree pipes. That should help them through the dry season.

Proud owners of a tractor

I'm still awaiting photos, but Mum reports the tractor is now officially ours and sitting in Dad's driveway. In her words, "it looks very nice"! :-)

More info from Dad's email on 25th:

I have arranged to get the tractor home to my place on Weds. The new front tyres are not yet ready for fitting. He hopes they will have arrived by Mon. With the work he has done and the tyres you have had a reduction in the price by $300-400. He is also giving the full service history and owner manual for the tractor and backhoe. I went up there to ascertain whether I had to jetison my garage door to fit the tractor into the carport, and have found it is not necessary at all. I do have to raise it as high as possible and then it fits like a glove. The overall length is perfect too. I need to obtain a posthole digger for it whenever, and some anchoring things for when it is on the trailer. It fits perfectly onto my tandem trailer. I need only to devise the ramp arrangement. With the hydrostatic drive it will be very easy to ease it up onto the trailer for anyone.

buying a tractor (perhaps)

Dad emailed yesterday to say he'd found a secondhand tractor he recommended that we buy.

We've toyed with the idea of getting a tractor a while. It would mean we could do all the excavations needed ourselves and save a ton on labour and equipment rental. And once finished, we could sell the tractor on again to recoup some of the capital outlay.

It is a B21 Kubota, 4 1/2 years old but has only 860 hours on the engine clock. It comes with a bucket and a backhoe, but not a posthole driller (although it is possible to buy them for it). Before selling, the dealer will be putting on new front tyres and replacing a bush in the front bucket, along with a new pin to lock the backhoe apparatus mechanically for safer transporting. We'll be getting a mechanical test done on it before decided to go ahead, but assuming that gives the all clear then it looks like I will soon own a tractor!!

From the description in the dealer's book:
"Extra heavy duty machine; For contractors requiring a heavy duty machine capable of handling long hours of operation in punishing conditions, the B21 is ideal. Specifically designed for the construction industry, the B21 has a reinforced frame, steel bonnet, cast iron front axle, heavy duty transmission and a 4 post rollover frame with steel roof. Features 4 wheel drive, self-levelling loader mechanism, industrial tyres, wet disc brakes, optional vertical stabilizer and optional 4-1 bucket (although the one we are looking at has a standard bucket, not the one that has a splitting capacity to more quickly fill it). HP 21, Engine 3 cyl diesel, Transmission is Hydrostatic, Backhoe has a max dig depth of 2330 and a reach of 3080. The Loader lift height is 2250 and lift capacity of 420 kg.

Priced new 18 months ago it was A$49150 + gst. The one Dad found second hand is A$25000. Still a pretty hefty sum, more than I've ever spent on a machine (I can see I am doomed to never have a new car!!) but given it's $500+ per day to rent the darn things that is only 50 days worth of rental... I am sure we will have more than 50 days worth of digging to do with all the excavation work needed for the garden, house, tanks, trenches for electricity wires, etc etc.

Apparently the hire firm selling it bought it new in order to rent it to one customer, a gas maintenance firm in Shepparton. It has been used by one team since new, has had all dealer services as required. Has had a new clutch plate installed 10 engine hours ago. The engine has only 860 hours total work time in the 4 1/2 years. It has been placed for sale because when it was returned from this firm for whatever reasons it meant there were too many in the yard for hire than the usual business pattern.

It weighs 1.2 tonnes, so should be okay for Dad to transport on his tandem trailer, meaning that it can be stored securely in town rather than left at the block. Dad assures me too there are ample service depots in Ballarat, and probably even in Marysborough, given it is a popular, tough machine.

update on wastewater plans

We're in the throes of trying to sort out the wastewater treatment system.

Even though it will be years yet before we install, we have to get the plans in place now in order to be get the building permit for the old house.

It's a little frustrating given that technology will no doubt advance in 4 years, but given that we've had no luck getting responses from local plumbers in Maryborough, it looks like we'll have to go with getting people up from Melbourne to quote and ultimately do the work.

(The way I figure it, if people aren't interested in helping us out now with a quote/plan even when we offered to pay for their time to do it, then they don't deserve our business in 2-3 years when we come to install).

We're in discussions with Septech, the company who won major brownie points nearly 2 years back by being the only one of 5 to respond acceptably to an email.

Dad has been to see them this week and I've had a phone conversation too, with a nice guy called Michael Pound. Michael needs to call the Amherst health officer (John Kelly) to clarify what the precise requirements are, and make a site visit before he can give a final quote. We'll then need to pay 20% deposit before he'll work on drawing up the plans.

The one hiccup is that in speaking to him it became clear that the system didn't do precisely what I'd understood it did. Although it does recycle everything: greywater and blackwater, treating it so it is safe for irrigation; because of stupid council regulations it isn't allowed to be stored!!

So you currently can't do what I'd envisaged, which was to store it in a special tank that could use to selectively irrigate the garden. It just waters it 24/7 along the 400m of irrigation pipe. And the pipe has all these restrictions on how far away from the house it needs to be etc so I can't even use it to water the courtyard garden which is the area that will need water the most. It's *very* annoying.

It's not a total writeoff though: there are trials underway with some councils in which they are letting people store the treated water to re-use on their property, and Michael said he was confident that by the time we come to live there it will be allowed. Fingers crossed.

Patch Rogers: arts & crafts dealer

If you like this era, you will love this shop. I stumbled across it by accident when I looked at a listing he had on Ebay. It looks like not only does he specialise in Arts & Crafts, Art Nouveau etc, he is heavily involved in gathering pieces for the Liberty exhibitions too.

You can see latest stock including photos and (for most) prices on his website here.