Yes, seriously, and anyone telling you otherwise is selling something. A quarter of the town's postcodes sit in the highest river-and-sea flood band. Over half sit within a few hundred metres of the coast. At the closest point, the water is seven metres away. This is a town that grew up on the edge of a tidal estuary, and the mapping has never once pretended it was somewhere else.
On the Environment Agency's mapping, about 25% of the area's postcodes fall inside flood zone 3, the highest river-and-sea band, with a further 3% in zone 2. Those two are exclusive bands rather than nested ones: zone 2 is the medium-probability fringe beyond zone 3, not a wrapper around it. Zone 2 being the smaller number is not a mistake in the arithmetic. It is what happens when the high-risk core is already large and the outer ring runs quickly into a hillside.
Surface water is not published here as a standalone share; it is folded into the postcode indicator further down. In a town whose streets drop from Townstal down to the quay, that matters more than it would on the flat. There is also the small matter of what the town is built on. Before 1671, what is now the centre was almost entirely tidal mud flats, and the New Road was laid across the silted-up bed of the Mill Pool after 1823. Water has a long memory for its own address.
Look forward rather than back and it gets heavier. Once the climate allowance is applied, roughly 32% of postcodes fall inside the river-and-sea flood extent.
For insurance, this is the sort of profile that changes conversations rather than ending them. Cover in high-risk postcodes is generally obtainable, often with a higher excess specifically for flood, and the price varies enormously between properties a few doors apart. The Flood Re scheme exists to help riskier homes get cover, though it does not cover homes built since 2009. Get an indicative quote on the exact address before instructing a solicitor, not after the survey.
At postcode level, counting anything that flags on at least one measure, including surface water alongside rivers and sea, around 31% rate high, 23% medium and 29% low. These bands overlap with the zone shares above and describe the same geography through a different lens. Adding the two sets together produces a number that means nothing.
The count of homes lands harder than any percentage. Across the postcodes that carry some flood risk at all, and only those appear in this dataset, the Environment Agency's rivers-and-sea mapping puts 1,595 properties on the register: 663 at high risk, 241 at medium, 157 at low and 9 at very low. Of the high-risk properties, 386 are residential. That is not an abstraction about a floodplain. That is a specific set of front doors.
Whether anything stands between those doors and the water is the question most flood summaries skip. Around 22% of postcodes sit inside high-risk extents with no defence present in the model, against about 25% inside high-risk extents where a defence is modelled. Defended means a structure exists in the model, not that the property is safe. Dartmouth has one recorded flood event on file, in October 2004, and its cause is listed as sea water overtopping defences.
Proximity explains most of it. About 56% of postcodes sit within 500 metres of the coast, a threshold the dataset defines rather than a claim about any single address, with a median distance of roughly 378 metres and a minimum of 7.
Every postcode here falls under a shoreline management plan, and the stated policy at the 20, 50 and 100-year horizons is to hold the line. That is an intention to maintain defences over those horizons. It is not a guarantee, it is not funding, and it is not a defence that already exists in front of your house.
For context on the direction of the sea itself, the nearest tide gauge at Devonport recorded a rise of about 2.35 millimetres a year across its record from 1962 to 2015. That is a measured historic rate, not a projection.
Flooding is the single worst thing about living in Dartmouth, and it is not close. The views, the water and the walking are genuine strengths here. They are also the reason the flood mapping reads the way it does, and no amount of estuary light changes what is in the model.