Pumping Out Holding Tanks?

[C08]

I was watching a programme about renovating an old commercial steel hull to form a large and superb "floating apartment" berthed on a drying pontoon somewhere up the Medway. Apart from the cost (£350k) it looked a good project apart from the surroundings of lots of mud (smell?) and some not so pretty dried out boats in various stages of disrepair.
The programme showed the lovely shower and wet room setup but did not elaborate on the holding tank arrangement and how as a static (no engine) boat you get can get the holding tank pumped out. Presumably there are mobile pump out boats but I have never seen these. The holding tanks must be very large and unless pumped out frequently the boatr would be unbalanced with such a large volume in the tank.
So my question is are there mobile pump out boats and what sort of what sort of cost is involved for a mobile pump out? Apology if this is a numpty question.

 

[RichardS]

Presumably they just pump out when the tide is in? :ambivalence:

Richard

 

[duncan99210]

If it's being used as a houseboat, they're often tied into the mains systems for power, water and sewerage. Otherwise I'd suspect simple discharge over the side rather than anything else, especially on a tidal mooring.

 

[C08]

If it's being used as a houseboat, they're often tied into the mains systems for power, water and sewerage. Otherwise I'd suspect simple discharge over the side rather than anything else, especially on a tidal mooring.

Thanks I wondered how that worked for houseboats. The programme I watched the boat was at the end of a long rickety pontoon, did not see any pipework for plumbing out or in. The thought of raw afflient going out into the drying pontoon on the Medway is a grim thought, and there are a lot of houseboats there!

 

[t21]

Thanks I wondered how that worked for houseboats. The programme I watched the boat was at the end of a long rickety pontoon, did not see any pipework for plumbing out or in. The thought of raw afflient going out into the drying pontoon on the Medway is a grim thought, and there are a lot of houseboats there!

Not too many affluents on the Medway, but those with £350k houseboat would be over the side first I suppose