-----In 2004 we bought a falling-down house and 30 acres. This blog documents our progress-----

Friday, December 02, 2005

plumbing and septic saga (part 1)

As part of the submission to get planning & building permits for the old house, we need to include information about the kind of septic system we will be using and water supply arrangements.

The general consensus is that it makes most sense to plan for systems to support both the old & new house. Even though it will cost us more in the short term, it'll save money in the long run.

For water supply, we're planning to put in some big water tanks up on the hill to enable us to get sufficient pressure from gravity feeding. They'll be filled by collecting water from the roof of buildings into the small storage tanks (the ones we've already bought several of) and pumping up.

We haven't decided on precisely which septic system to go for yet as it will depend on pricing, but provided it is suitable for our soil and not outrageously more expensive I'm strongly in favour of an aerated-type system rather than the traditional septic tank. This way, we'll get to recycle more of the water.

This was all too boring to blog as it happened, but I wanted to keep a record of it. So, this is a compilation of all the plumbing and septic related discussion that happened in November:

From Dad's email (Nov 11th):
"We have to have a plumber submit a plan for septic system. I
managed to get a Maryborough plumber to see the place while I was
up there. There was a list provided by the council surveyor of plumbers
who are able to do the work in the area, and I called 6 before I got
onto the chap who was willing to come see the place and discuss with me
the placement of the required service. The plumber must submit the
plans for the septic before a permit to build can be approved. Also a
plumber must do all the plumbing work.

I discussed placement of the header tank for the water supply to obtain
pressure to service the system. We will be placing the tank in the
passage above ceiling in the roof space. That position will afford
adequate pressure for hot water to the laundry and ensuite. It will
be less obvious than on the roof of a veranda. It will be well
protected against water damage should a leak occur. The old tank
will be tested and if it is still good and can be used we will place
it there. Otherwise we must get another. The plumber mentioned
also that we need to have a tank higher up the hill or on a tank
stand that will give adequate water pressure for the house.

There is a minimum supply of water required for the permit to be
granted. We require 20000 litres ready to supply for fire fighting,
and a minimum of 5000 litres of potable. We have when full 13,638
litres as they sit now, but we need greater pressure for the house
and future house.

I propose we place a 5000 gal, that is 22,730 litre, tall profile
tank as far up the top of the hill as possible. That is just where
the peak of the roadway to the hobbithouse passes by the fenceline.
Since we must not build on the fenceline I propose we bring in to
the inside of the roadway and plant more trees or such to obscure
it. The most efficient size tank that can be bought is the 5000
gal for cost/capacity/placement. I will obtain a price for you
before doing anything. That way we have to pump the water up to
the top tank periodically. The new house should be served thus
for the firefighting capacity with this tank so placed. I prefer
to not be relying on electricity to fight a fire. The dam is too
distant for the firefightting, except as a supplement supply.
We could meet minimum firefighting needs with the pump we have
if the dam were closer to the house. But precious moments are
lost while setting up a system, and the gravity system is
always at the ready."

Nov 12... extracts from my reply:
"I was a little confused about where you were talking about
putting the giant 5000gln tank... you talked about a roadway to
the hobbit house but there isn't one (or there isn't meant to
be one)... But then I realised you must be talking about the
dirt track that runs through the forest along the fenceline at
the back of our place? I'm still not entirely sure when you
meant exactly but where we'd been thinking the giant tank would
go is behind the old/new house, up the hill as far back as it
can go near the fenceline... but NOT crossing over to the other
hill where the olives are planted & where the gum trees have
started to come in from the forest & where you were thinking of
building your cottage initially. We want to keep all that area
looking natural as we have plans for it as part of the garden".

Nov 12... extracts from Dad followup mail:
"Sewage can wait a bit I think, but still need to hear from
plumber after his talks with the health and sanitation person
about whether we ought to provide for the new house when doing
the system now. That will be a bigger system of course, but
may be cheaper than doing two systems. But it may be better
to have two systems. If costs are right, will go with the system
for new house as that will not be emptying towards the dam. I
think the place for the septic is in the courtyard, if access
by truck is possible into this inner sanctum. I haven't an
idea how large this will be and where the plantings will be,
and so maybe having the sewage elsewhere, say to the back of
the house, is the best plan....

I read of your thoughts of having the large tank behind the house.
If you do that you must go to the concept of using a pressure pump
system rather than a gravity fed system for your water supply. This
way supposes a consistent access to electricity, and so supposes
going on with the other power supply options. I have a suggestion:
Place a 5000 gal tank up on the highest place we can get it. Plant
things to hide it. If when all things are in place for the new
house and new power supply, simply move it somewhere else. A
gravity system is really the only practical system at present.
The woodstove has to be a gravity system to work properly".

On Nov 13 I replied:
"We don't mean to put the tank behind the house close to it,
but instead far up, way near the back fence. This is still going
to be quite high. We don't want it to be on the hill near the
olive trees. If at the fenceline behind the house still isn't
high enough for gravity feed, can't we put it on a tank stand?
For the big tank I would rather put it in it's ultimate place
rather than somewhere that we'll want to move it from. Because
what will end up happening is that it'll be too much hassle to
move so I'll be stuck with it.

In terms of the sewage treatment approach & position, I want to
consult Eric about that as well as Prue. It can't go in the
courtyard area because that will be all dug out to replace the
soil for planting etc. It also shouldn't go next to the old
house in the part that will be next to the kitchen for the new
house, because the plan is for that to be a herb garden area.
Probably it could go out the front of the old house (not sure
how close that is to the gas line though) or down the slope to
the side a bit further towards the dam... but if you can wait a
little while before deciding precisely where it will be then I
can doublecheck with Prue. But first, I want to check with Eric
about the kind of sewage treatment he suggests".

I then got in touch with Eric in case he had any other suggestions about placement of the tanks and choice of septic system type. Here are extracts from his reply...(Nov 14):

"The planning permit will often contain a condition about water
supply for fire fighting. The dam may be enough. In any case, I
always like to put CFA outlets (to connect to fire hoses) on all
water tanks just in case. They add a little cost to a tank (about
$100) but it's a good idea. 5000 gallon tanks aren't that big.
About 4-4.5m in diameter. I'd probably suggest a couple of them.
You will have plenty of roof area to catch water. We used to have
two 5000 gallon tanks plus the dam for some items and never had
any problems. Larger, site built tanks are another option, but
they require a larger flat spot. I'm not sure about the relative cost.

The septic system will need a separate permit where the type of
system will be nominated. Standard septic systems are the cheapest.
There are other options as well which I described in the Design
Brief. Approved systems are shown on the EPA website.
The shire may also require a Land Capability Assessment which is
a report analysing the site, and recommending a system design. If
you need one, the same person can often do a soil test for the
building at the same time. I often use Provincial Soil Services
in Ballarat for that kind of thing"

We looked at the site Eric recommended and freaked out at how many options there were. So then Dave spoke to Eric to get more clarification. This is from a Nov 17 email written to update Dad about Eric's comments, as relayed to me by Dave:

"Eric too thinks it will probably make the most sense to plan
for the one big septic system now to suit the needs of the new house
as well as the old house. This is particularly the case if we want
to go with an alternative to the standard septic system which is what
we are strongly leaning towards. The two broad approaches are either
to shove it all in a tank, or something (that the name escapes me but
it's something to do with aeration) where you have an area that it
goes to and is treated underground naturally... there are lots of
different variants on second type as it's still relatively new-ish.
At the website he lists above there's a link to see all the EPA
approved systems.

The reason we are interested in the second alternative is that they
are much better in terms of recycling water and we need all the water
we can get, frankly, for the garden. They are a bit more expensive
but he did a project recently where he was surprised how little
extra cost it was... basically, it cost only $1000 more to get the
alternative system than a traditional septic tank. $1000 is not a
lot to pay for extra water over the course of years. Our situation
might be different but I would like to consider an alternative
approach not just assume we go with the standard septic tank of old.

For instance, these are some pictures of lovely garden beds looking
all lush & well watered even though the surrounding areas are very
dry. This is all due to the subsurface irrigation from the effluent
& it improves the soil too. You can't grow food on it but it'd be
great for lawn or a 'bog garden' or whatever.

photos of septic system garden beds(nb: both pictures come from the pdf "guidelines for aerated onsite wastewater treatment available here)

Have you heard of these systems before? Do you think the plumber
in Maryborough knows about them? I'd assume he must as they're not
brand new but I don't really know how it works... perhaps for some
you have to work directly with the system manufacturer to get one of
their approved people to install it. I don't want to create hassle
for you but as part of the purpose is to have a lovely garden there,
this seems like a very good option to explore & I'm strongly in
favour of anything that is better for the environment. "

On Nov 17th Dad replied, with regards to the question of the water tank placement:
"We can overcome this problem by placing a platform over the
5000gal tank to support a 300 gallon tank like I put at Dawn's place.
The large tank will add to the stability in the high winds of a tower
high enough to give pressure to the secondfloor of the new structure.
For the old house, we can get by with putting the 5000 gal there and
connecting it for the firefighting requirement, as it is sufficiently
high for a singlestorey building, even with the tank of the hotwater
service in the roofspace. So if you are planning to not have any
visible tanks on the hill, so be it. You could place a low profile
tank "over" the hill for a short way and still achieve a substantial
elevation advantage for water above the new house, yet not have a
tower to look at".

... and then my reply, agreeing..
"That sounds like a good arrangement. I can imagine ultimately
perhaps using the platform as a bit of a lookout... and maybe if we
extended it out in front to create a sort of verandah effect underneath
the 5000gal tank it would be useful as a makeshift barn. Anyway, we
don't need to decide on any of that now, the beauty of the plan is
that we put just the 5000gal one there for now as that on it's own is
enough for the old house".

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