Parnell Poo Pipe

[Steve 34]

So lets play with some more sh*t.

Approximate size of the Hauraki Gulf, 2000 squ km, about 50km across and 80 km N to S.  Bit of a triangle shape and a couple of islands in the way so halved 4000.  Roughly 2m tide range twice a day.  Each square km will lose, then gain 2 million tons twice a day. 2 million x 2 x 2000 = 8 billion tons.  Lets say that only 5% of that water washes up and down the ditch.  So 400 million tons over 3 weeks = 8.4 billion tons of flushing past North Head.  Versus what? 27 million litres of very diluted poos and wees.  So for every time you flush 1500 x 44 gallon drums of sea water gets poured on top. Environmental Disaster?  Whatever.  It's why God made tides and microbes.

Enough fun talking sh*t, better do some work.

[K4309 258]

I had a go at calculating the volume of tide coming in and out of the Harbour each day.

Width of harbour (North Head to Bastion Point) 0.8nm

Average depth 15m (max depth 25m there but a lot of the channel is deep up to the edges).

Average tidal stream of half a knot. Counting only 12 hrs / day of tidal stream (half in, half out)

The daily volume of tide flushing the harbour in litres is therefore 2.47x10^11 

Or, 2.47 times 10 to the power of 11. 

Basically it is so much water I can't count the zeros. If I've got my zero's right that is 250 billion litres per day.

So I'll take your 8.6 million litres per day and raise you 250 billion litres.

Another way to look at it is 0.0003% dilution.

I'd be impressed if you could test that accurately. Probably why there are no actual test results anywhere.

[K4309 258]

Anyway, enough of the complicated maths and actual facts and stuff.

There is a theory going around that the ban on racing is nothing to do with the blocked Orakei trunk sewer but is actually a ruse by Punuku to demonstrate that there is no need for yacht racing on the Harbour. It is a demonstration that the yachting community are a complaint group think bunch that are easily led and easily manipulated. Case in point the Landing Hardstand.

Once Punuku have demonstrated there is no actual demand for yacht racing, and all the yacht racers have gone and taken up golf (or motor racing in water-rat's case), then Punuku will be free to take all the marina's, and more importantly the marina land, and put large high end apartment blocks on them.

This is all for the greater good of course, in that after years of Socialist Mayor's the city is broke, and we need to pay down debt, and of course enable some really lucrative property development deals.

As its already been demonstrated there is no need for yacht racing, and no one really cares, then it will be an easy and straightforward job for Punuku to get their hands on the marina land and finally do something productive with it.

[Steve 34]

I knew I'd stuffed it up so I changed litres to tons.  That dilution is quite possibly within the rules.

Resource Management Act says 50ml per litre is ok for discharge.  That's .05%. (Before Discharge)

With your tide getting it down to 1/1000 of that, we're all good for swimming I reckon.

 

[Psyche 633]

Maybe so but you have to take human nature into account, i.e if you take one tiny dump in the local pool no matter how you try and explain that its ok, it's going to empty out pretty quick!   People dont like swimming in it no matter how diluted if they know its still pouring in.

[Steve 34]

Nothing worse than floating into a floater.

[K4309 258]

18 minutes ago, Psyche said:

Maybe so but you have to take human nature into account, i.e if you take one tiny dump in the local pool no matter how you try and explain that its ok, it's going to empty out pretty quick!   People dont like swimming in it no matter how diluted if they know its still pouring in.

There is an assumption there isn't normally wastewater and other pollution entering the harbour. That isn't the case. The only difference with this one is it's being publicised. 

[Black Panther 1,587]

All this makes wonder why we bother with holding tanks 

[Steve 34]

Because of incoming tides I guess.

 

[K4309 258]

1 minute ago, Black Panther said:

All this makes wonder why we bother with holding tanks 

I can answer that.

Boys trip when we first got the boat, maybe 1999, well before holding tanks were a thing.

Gorgeous crystal clear water, eastern Barrier. One of the boys wakes up and goes for a refreshing morning swim in the amazing water. One of the other boys wakes up and goes for his morning bowel movement. Screams of disgust and yelling as morning swimmer sees a plume of last nights curry emanating into the crystal clear water he is swimming in.

Basically boats anchor in nice bays where people enjoy in-water activities. You need some separation between waste and in-water activities. Noting we are discussing banning yacht racing here, not harbour swims.

[waikiore 399]

Except that for our older yachtsmen (me included) who recall clearly the days prior, everybody did a little everywhere -now we have large launches exiting Bon Accord , North Cove , Man-o-war and inner Fitzroy and immediately dumping a concentrated 1000 +litres in one place -this has been proven in the states and Europe to effectively kill the bottom in that area. Hence the move away in parts of America from holding tanks, lakes and inland waterways excepted. I dont know of any M class or 18' skiff sailors who suffered sailing past the sewer at Orakei when it was in full flow prior to Robbie getting Mangere underway, people used to fish there surrounded by the ever present seagulls -which we still see off the North Shore outflows . So all we need is a little perspective and a lot less hysteria.

[Psyche 633]

Bucket and chuck it, I say!

[Black Panther 1,587]

+1 for the airhead 

[aardvarkash10 960]

Everyone focuses on flushing toilets, but the majority of auckland sewerage is grey water, a lot of it commercial and industrial.  That makes the 250l claim a page ago quite plausible especially given the total water consumption in Auckland.

Survivor bias helps explain the lack of any recollection of historical water-borne infections or outbreaks of disease.  Bear in mind, the current thinking is that the most likely cause of Queenstown's recent infection outbreak is one infected person pooing in Lake Whakatipu.

You all can swim or whatever if you like, I'll stay out until the all clear siren sounds.

[Bradz 18]

10 hours ago, K4309 said:

I can answer that.

Boys trip when we first got the boat, maybe 1999, well before holding tanks were a thing.

Gorgeous crystal clear water, eastern Barrier. One of the boys wakes up and goes for a refreshing morning swim in the amazing water. One of the other boys wakes up and goes for his morning bowel movement. Screams of disgust and yelling as morning swimmer sees a plume of last nights curry emanating into the crystal clear water he is swimming in.

Basically boats anchor in nice bays where people enjoy in-water activities. You need some separation between waste and in-water activities. Noting we are discussing banning yacht racing here, not harbour swims.

Nothing like the outflows in Tahiti et al... the solution to pollution is dilution was the response we got when last chartering up there, no holding tanks.

[Bad Kitty 252]

On 13/10/2023 at 8:38 AM, Steve said:

I think we need to do a bit more maths.  Lets say that a tenth of Auckland's sewage is being spilt.  I know its way less.

So lets allow 4 flushes a day per person @ about 10 litres per flush.  Remember its only a couple of hundred mils per pee mixed with that 10 litres, but lets disregard that and call all 40 litres raw sewage. Roughly 1.6 million people live here so 160k x 40 = 6.4 million litres per day.  That's 74 litres per second not 250. 

If we factor in the immediate dilution of that sewage with 40 litres of water you might be looking tops 20% of that.

Say 15 litres per second of actual poos and wees.  I get 27000 tons not 450000 tons over 3 weeks.

So its probably somewhere in the middle.  Not trying to say anything at all. 

Just playing with sh*t.

Either number is unacceptable, it's 2023, not 1823.

NZ's infrastructure building & maintenance is pretty 3rd world. 

[K4309 258]

16 hours ago, aardvarkash10 said:

 Bear in mind, the current thinking is that the most likely cause of Queenstown's recent infection outbreak is one infected person pooing in Lake Whakatipu.

 

That is the best piece of PR spin to ever come out of a Council.

QLDC have a policy NOT to have constructed overflows on their wastewater network. Every other Council in the Country have constructed overflows. A constructed overflow is a point where, when there is a problem with the network, you know exactly where your wastewater will spill. Once you know where your network will spill, you can monitor it so you know WHEN it is spilling. if you are really flash you can even work out how much it is spilling, and put inplace other mitigations to reduce the impact of a spill (normally gross solids screens, keeps the lumpy bits out of the lake).

In short, QLDC have no way of knowing if and when their network is spilling. Something as simple and common as a fat-berg could cause a spill from the Queenstown wastewater network into Lake Wakatipu and QLDC wouldn't know about it. 

The main issue is that all streams lead into Lake Wakatipu, including from all the urban areas, along with livestock and farming areas. What then happens, is QLDC take effectively untreated drinking water straight out of the same lake. That is about as logical as taking drinking water from one side of your boat, while discharging the heads out the other side, without a holding tank (assuming you were on a fresh water lake).

Due to the extent of the outbreak, it is not possible that this was caused by one person taking a poo in the lake. This was clearly an extensive and long discharge of wastewater into the lake. I'd bet a good bottle of whisky, given the time infections started becoming apparent, that this all started in a winter storm with heavy rain and flooding in July or August. It's wastewater 101. Heavy rain inundates the wastewater network and causes overflows and spills. That all flushes into the lake, along with all the general detritus from land. QLDC suck that same water out of the lake, chuck some pool chlorine into it on the way past and pump it up to your house for drinking. Without actually treating it for known waterborne pathogens (crypto).

This notion they are putting around that one single person took a dump in the lake and that caused the outbreak is blameshifting 101. It is also implausible.

[Psyche 633]

Considering that trunk line was built in 1910, youre not too far off. The reality is that a lot if NZ's  water and wastewater infrastructure is in a pretty poor state bar a few exceptions.  Its not like a shiny new road, you cant see it so its not important and no one wants to pay for it. Enter 3 waters or something similar but no one wants central planning either.  

[K4309 258]

13 minutes ago, Psyche said:

Considering that trunk line was built in 1910, youre not too far off. The reality is that a lot if NZ's  water and wastewater infrastructure is in a pretty poor state bar a few exceptions.  Its not like a shiny new road, you cant see it so its not important and no one wants to pay for it. Enter 3 waters or something similar but no one wants central planning either.  

Central planning isn't needed for water reform. The main issue is access to finance. In general, the bigger the organisation the easier the access to finance (in the context of a butt-f*ck-nowhere Council and a large organisation like Wellington Water or Watercare. At the same time there are economies of scale, especially in technical knowledge and competence in large organisations. The best example of that is the roading manager looking after the water supplies in Havelock North. That Council wasn't big enough to have a technical specialist in charge of their well-heads.

On the Orakei Trunk sewer collapse, this is basically unfortunate. Watercare had identified the risk a long time ago, and put in place a project to reduce that risk and eventually decommission that trunk sewer. The only issue is that project is $1billion, and with a construction programme of about 10 years, give or take. It's about half way through now. So in 5 years this wouldn't have happened. Given its been in service for 112 years or something, that is well within the margins of error for the planners.

Personally I think the basic issue is that as a community we need to spend more on infrastructure. Our 3 year election cycles and short term political outlooks just don't accommodate that. Hence moving 3 waters out of the political realm and into CCO type stuff. (if only it could be moved without all the baggage of co-governance and what not).

[Psyche 633]

I agree, the consensus amongst people who know a lot more than me is that we are about 200 billion behind where we need to be. But as I mentioned, infrastructure is unsexy and tax cuts are very sexy! Very much