There is something rarely said out loud about coastlines: what isn't decided gets decided anyway.
It happens slowly — lot by lot, permit by permit, road by road. Each choice looks small and reversible on its own. But after twenty years, those choices add up to a landscape, an economy and a community that no one actually designed.
The question isn't whether the open land along the bay of São Martinho do Porto will stay untouched forever — it won't. The real question is how to respond to the pressure that will inevitably build on it: through a vision considered at the scale of the whole bay, or through a string of one-off decisions that nobody ever chose together.
The bay cannot be built lot by lot.
The image accompanying this article was generated by artificial intelligence. It is not an urban plan. It does not represent the municipal council, any public or private entity, any landowner or developer. It is not an investment proposal, nor a prediction of what will happen.
It is a visual exercise.
Its purpose is to make a question tangible that usually stays too abstract to grasp: what would São Martinho do Porto look like if the bay's future were designed on purpose, instead of decided by a string of unrelated planning permissions?
The image tests a few principles: low-rise buildings, construction organised into discreet clusters, ecological continuity, walking and cycling paths, responsible water management, public space, and phased development.
The numbers that appear in it — density, height, percentage of green space — are illustrative parameters, not technical recommendations. They do not replace environmental studies, economic analysis, spatial planning instruments, or a public decision-making process. This piece is an independent editorial reflection on the territorial future of São Martinho do Porto, and it does not promote any development or investment opportunity.
But they help put the conversation on the right ground.
This isn't about whether you like or dislike an image made by artificial intelligence. It's about whether we want to discuss the bay's future before the first decision makes every decision after it inevitable.
A bay is not the sum of its lots.
It is a single landscape, ecological, economic and social unit. What happens on one shore changes how the other is experienced. A new road changes traffic patterns. A car park can change the relationship with the beach. A cluster of buildings can affect the view, the wind, the drainage, and the sense of scale of the whole place.
The bay isn't just a stretch of water ringed by available land. It's a lived landscape: a waterfront, a town, roads and access points, shops, permanent housing, seasonal activity, and a daily relationship with the sea. Any new development will have to fit into that system — not just satisfy the boundaries of the lot it's built on.
That's why the decisive question isn't only "what can be built on this lot?" It's also:
What happens to the bay if every similar lot gets developed the same way?
A single building can look discreet on its own. Ten buildings can change the landscape. A network of access roads, walls, car parks and infrastructure can transform a territory completely, even if every individual project was approved on its own merits.
The cumulative impact rarely shows up in the first planning application. It shows up later, once there is no longer an alternative vision left to choose.
Arguing for a territorial vision doesn't mean arguing that nothing should be built. It means accepting that construction should answer to an idea of place, not just to the availability of land or the return on any single lot.
The image proposes low density. But low density does not automatically mean sustainability.
A lightly built landscape can preserve views, reduce visual impact, and create a gentler relationship with the land. But it can also consume more land per resident, increase car dependency, demand more infrastructure per household, and produce a community that is seasonal, expensive and hard to access.
Low density is only a solution if it's part of a wider strategy: careful siting, height limits, permeable ground, ecological corridors, walking and cycling mobility, accessible public transport, water management, energy efficiency, housing for residents, local services, and permanent upkeep of the landscape.
Building less isn't enough. You have to build better — in the right place, at the right scale, with clear responsibilities attached.
It would be easy to defend a low-density landscape as if planning decisions were purely a matter of taste.
They are not.
For landowners, buildable area represents value. For investors, density determines returns. For construction firms, it represents volume of work. For the municipality, new development can mean revenue — but also new costs in roads, lighting, sanitation, waste, transport and maintenance.
Less construction per hectare can mean lower immediate returns. That pressure is real, and it should be acknowledged, not hidden behind environmental arguments.
But the value of a coastal territory isn't only in how many square metres can be built. It's also in what gets preserved: the view, the quiet, the scale, the closeness to nature, the authenticity, and the possibility of living there year-round.
A preserved landscape can create economic value — but that value is only socially defensible if it comes with public access, jobs, housing and concrete benefits for the community. If every landowner maximises their own lot's buildable capacity in isolation, everyone risks losing the shared value that makes the bay desirable in the first place.
That only works with a governance and financing model that ensures the value the landscape creates doesn't get privatised entirely.
Who pays to maintain the green spaces? Who looks after the paths? Who guarantees drainage works? What does the community get in return? And how do you stop a project marketed as sustainable from being, in practice, just a second-home development with more grass between the buildings?
These questions are what separates a territorial vision from a marketing image.
Any vision for the bay should start with a question tourism planning often forgets: who will actually live there?
An area can look green, integrated and discreet, and still be made up almost entirely of second homes or seasonal rentals. It can have beautiful views and few services. It can be full of life in summer and economically silent in winter.
São Martinho do Porto's future shouldn't be measured only in beds, units or transactions. It should also be measured by its ability to form an actual community.
That means thinking about year-round housing, solutions for local workers, neighbourhood shops and services, spaces for families and older residents, accessibility, permanent employment, and integration with the existing town.
The landscape can be the starting point. But a destination only stays alive when it has people, relationships and activity beyond the tourist season.
São Martinho do Porto today has a sizeable international resident community, including English-speaking residents who chose to live there year-round, not just visit. That presence belongs in this conversation: whoever lives on the territory all year knows its rhythms, and knows exactly what stands to be lost with change that moves too fast.
But it would be a mistake to frame this as a standoff between a Portuguese community and an English one. The reality is more layered than that: there are permanent and seasonal residents, owners, tenants, workers, shopkeepers, young families and older residents — each with a different relationship to the bay. The test for who gets a seat at the table shouldn't be nationality. It should be a real, concrete relationship to the place, and a willingness to take responsibility for its future.
A decision of this scale shouldn't reach either community only after everything has already been settled. It should be discussed before that point, while alternatives are still on the table.
There are international examples that help think through these choices, even though none of them can be transplanted directly.
Sea Ranch, in California, is remembered for how it integrated architecture, topography, vegetation and shared open space. Its real lesson isn't a particular architectural style. It's the idea that rules governing siting and landscape protection need to be set before development becomes irreversible.
Grootbos, in South Africa, demonstrates a different principle: conservation can be part of the economic model itself. A preserved landscape isn't only a cost — it can be the foundation of a higher-value tourism experience. It is not, however, a residential development, and it isn't a direct comparison for São Martinho do Porto.
Closer to home, Comporta shows the economic power of low, unobtrusive architecture. But it's also a warning: low density does not, on its own, guarantee sustainability, accessibility, or any benefit for the people who actually work and live there.
None of these examples offer a ready-made formula. What they demonstrate is simpler: the rules a place sets for its own development shape the kind of value that development ends up creating.
The question isn't only how much gets built. It's what kind of economic, social and landscape outcome the place is trying to produce.
The idea of phased development deserves attention on its own.
Phasing doesn't mean simply splitting a development into commercial stages. It means allowing reality to be checked before the next stage goes ahead.
A first phase should let you find out whether mobility actually meets demand, whether drainage holds up, whether the green space is genuinely preserved, whether public services can keep pace, whether there's demand outside the summer, whether it created local jobs, and whether the community feels it received benefits proportional to the impact.
Only after answering those questions would it make sense to consider the next phase.
Phasing isn't about slowing development down. It's about stopping the first phase from making every phase after it inevitable.
In a context of climate change, pressure on water resources and economic uncertainty, building everything at once may be less prudent than moving forward with the capacity to adapt.
Responsibility can't fall only on the owner of each lot, or only on whichever developer brings the next project forward.
The municipal council has a central role, but it shouldn't be the only participant. Landowners know their rights and expectations. Developers know the financing and operating conditions. Residents know how the place actually functions day to day. Shopkeepers and workers know the real economy. Environmental and infrastructure bodies know the territory's physical limits.
Before individual planning permissions are granted, there should be a shared vision for the area around the bay, backed by an environmental and mobility assessment, alternative development scenarios, an evaluation of water and sanitation capacity, rules on height and permeability, targets for permanent housing, mechanisms to protect shared spaces, and indicators to assess each phase.
This doesn't mean replacing the legal instruments that already exist. It means giving them a shared direction and an ambition that goes beyond reviewing each lot in isolation.
The image is not a plan. It doesn't resolve the questions of ownership, legislation, infrastructure, financing or viability. But it can help start a conversation while that conversation still has a point.
The moment to discuss a landscape's future is before it becomes a string of settled facts. After the first planning permission, many alternatives start to disappear. After the first road, the next development becomes more likely. After several projects are approved, the sum of them gets presented as inevitable. But what looks inevitable at the end is often only the result of no decision having been made at the start.
It shouldn't be inevitable.
São Martinho do Porto can still choose between letting its future be drawn lot by lot, or building a shared vision for the bay.
The question isn't simply whether you're for or against development.
It's this:
If we set ourselves a fifteen-year horizon to think through São Martinho do Porto's future on purpose, what would we want to see from the window — and what responsibilities would we be willing to take on to keep that landscape alive?
Image: speculative visual exercise generated by artificial intelligence, August 2026. It does not represent any project, municipal plan, or real investment proposal.