A harbour site usually has six pages: home, berthing, facilities, gallery, news and contact. A skipper arrives with a specific question — annual or seasonal, what length, what draft, is there a hoist, can I stay three nights in August — and finds none of it. The aggregator with a filter for hull length answers instead, and takes the enquiry for a berth you may well have free.
Availability is the second leak. When berth lists live in a PDF or behind a phone call, search engines have nothing indexable to rank. A PDF cannot carry structured data, cannot be updated by your harbour team in five minutes, and gives no path to an enquiry form. Written availability pages, marked clearly as indicative, outperform a dead download every month of the year.
Seasonality is the third. Search demand for moorings rises sharply in early spring and again before winter layup. A site whose last news post is two seasons old reads as dormant to both visitors and crawlers, and Google quietly prefers competitors publishing fresh notices.
Facilities are the fourth. Fuel, repairs, storage, chandlery and pump-out are separate searches made by people already on the water, often within a few miles, often on a phone. Without a page per facility, those visits land on a generic "facilities" paragraph that mentions everything and ranks for nothing.
Trust is the fifth. No named harbourmaster, no pilotage or approach notes, no clear visitor rules, no photographs of the actual pontoons, no reviews, no directions and no map. For a first-time visitor deciding where to tie up in the dark, that absence is expensive.
Groups add a sixth problem: three marinas, one shared template, three identical "About us" pages. Duplicate content, competing canonicals and a map pack that cannot tell the sites apart. Fixing that is architecture work before it is copywriting.