The RYA has been doing some work on a slipway guide and I had been asked to comment. So an unusual post but it includes the link and part of our conversation.
https://dinghytrails.uk/south-west/ look at Plymouth
Additionally
https://www.plymouth.gov.uk/slipways
I was asked my opinion on the information and replied with this
Plymouth council do a good job a maintaining the slipways you have mentioned. I live on the Cornish side and as a member use the Torpoint Mosquito sailing club slip. This ends at low water springs but the foreshore is hard so I can hand launch at all states of tide. This is apparently connected to a public slip so could be used by the public.
The issues with this slip are however, the adjacent marina is a commercial operation and they use the slip and leave vehicles parked on it. Additionally the there isn’t any public car-parking other than out in the street so probably not the most suitable.
Because I have this facility I have only ever used Jubilee Green and Mount Batten on rare occasions. I have walked past most of the others and would say the descriptions look ok.
Mount Batten is fine, a great resource but it depends on where you want to go and tides. It’s great for heading out to Plymouth Sound.
Jubilee Green / Saltash Town, I think in needs emphasis for both how strong the current is (it’s lightly mentioned at Jubilee Green). Careful tidal planning is required if launching a dinghy here, additionally for Jubilee Green there is the added hazard of a long jetty / pontoon bridge close down stream. Many of the moorings in Saltash are long trots again something to be factored in.

The Barbican dinghy pontoon dries out I would say an hour each side of low water springs.
There is an all tide pontoon that costs £10 and I think the way the authorities are going
For DCA Rallies people use Jubilee Green or Mount Batten so focusing on those two is probably key.
If planning a trip it is worth noting that the Tamar has two restraining sections
- the narrows, the entrance area at Devil’s point
- Saltash passage, under the bridges
These have strong currents and so I always go through them with the current with me.