Planning departure times for tidal harbors

After this year’s 24-hour race on the IJsselmeer, we had some confusion about the right
departure time for the trip back. Nothing dramatic, but with a tired crew and too little
sleep, combining tide tables, route notes and local knowledge was more
annoying than it should be.

That became the trigger for a small side project: wanneermoetikweg.nl
(https://wanneermoetikweg.nl/).

The idea is simple. Pick a departure harbor and a destination, and the site shows
possible departure windows based on the relevant high or low water, available route
advice and current water level data. The calculation itself is not very complicated. The
useful part is bringing information together that normally lives in different places.

Where possible, the site uses public Rijkswaterstaat data. The route information is
still manually collected and checked, so treat it as a planning aid, not as a navigation
source. Always verify official sources, current charts, weather and local conditions
before leaving.

The project is partly vibe-coded, partly carefully reviewed, and very much a hobby
project. It is useful already for a number of Dutch tidal routes, and I’ll keep
improving it when I run into missing routes or bad assumptions.

Try it here: wanneermoetikweg.nl (https://wanneermoetikweg.nl/)

There is also a short FAQ: wanneermoetikweg.nl/faq (https://wanneermoetikweg.nl/faq)