Water trails

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Logo. Feature : Water trails
One example for Feature : Water trails
Description
Canoe and kayak trails
Tags

canoe=*, portage=*

Water trails, also known as paddle trails or blueways, are waterways suitable for travel via canoe or kayak. This page presents recommendations for how to map water trails in a way that's useful to data consumers. These guidelines are based on canoe mapping performed in the US and Canada, but may be applicable elsewhere.

Rationale

Water trails form transportation networks similar to the road, rail, and pedestrian networks. However, water trail data tends to be fragmented and difficult to find, when it exists at all. Some government and nonprofit entities release maps for water trails they manage, and paddling guidebooks may be available for popular routes. This information can be invaluable to paddlers, but runs the risk of being incomplete, out-of-date, siloed, and non-machine-readable. Compiling water trail data in OpenStreetMap supports comprehensive trip planning, routing, and mapmaking use cases while allowing the public to provide continuous updates.

How to map water trails

information sign

Warning: careless mapping could place someone in mortal or legal peril. Only certain segments of waterways are safely paddleable. Dangers such as dams, weirs, waterfalls, rapids, tides, obstructions, open water, low water, low bridges, marine traffic, and water intakes must be accounted for. Weirs especially are "drowning machines": see a quick explainer here. Put-ins, take-outs, and portage routes are sometimes informal with complex access restrictions. As with trails on land, do not assume a waterway is safe and open to recreation without an appropriate source. Do not simply tag an entire waterway as canoe=yes without proper review.

1. Find source data

Choose a water trail to map. Find a reliable and license-compatible source for your data. Common data sources are watershed conservancies, state agencies, guidebooks, online trip reports, or your own experience. Note that even good data may be incomplete or out-of-date. Consider compiling multiple sources if available. Do not add data you are not sure about.

2. Prep waterways

Note: In many cases, the waterway may be part of, or glued to, a boundary relation. Even if you know a boundary is legally defined as the center of the river, it can still be helpful to separate boundaries from waterways before mapping water trails. This helps you to avoid messing up boundaries when adjusting the geometry of waterways, splitting them to add segment tags, connecting ways to them, and adjusting their relations. Similarly, consider separating waterways from the edges of landcover features; you can glue them along riverbanks instead.

Start by making sure all the waterways involved in the trail are fully mapped. River/stream/canal geometry should be drawn in relatively high precision along the centerline of the feature. Add any major side streams around islands as separate ways; paddle conditions often differ on opposite sides of islands so we need to be able to tag them separately. Make sure segments through lakes and reservoirs are drawn and consider tagging them waterway=flowline.

All segments in a waterway should be connected from source to mouth to enable routing. WaterwayMap.org is a handy tool to identify gaps in the waterway network. Include segments that flow through lakes or reservoirs. You can add the waterbody:name=* tag to these segments so routers can say things like "paddle 1200 ft across Whitney Pond."

It's helpful to group all segments of a waterway into a waterway relation. This makes the waterway easily viewable and downloadable, and helps Q/A tools. You can add a wikidata=* tag if an item exists for the feature, to make it more linkable (note there may be many waterways with the same name, make sure you link the correct one).

3. Identify hazards

Manually review the entire route via aerial imagery to find all obstructions and rapids. Pay special attention to waterway=dam, waterway=weir, and waterway=waterfall features; these are major dangers to paddlers. Tag all sections of rapids on waterway segments using the rapids=* tag. Even mild rapids can pose danger to unprepared or inexperienced paddlers.

Add all roads (including driveways), paths, and railways that cross the waterway. Add the tunnel=* tag to culverts and piped segments of waterways. Add the bridge=* tag to bridges, and preferably add covered=yes to waterway segments under bridges to indicate potential clearance issues.

If known, add the tidal=* and intermittent=* tags to waterway segments to alert paddlers to common water level issues. Only use intermittent=yes if a waterway runs completely dry; do not use it just because a stream is sometimes too low to paddle. While it may seem like overkill to add tidal=no in Montana or intermittent=no to the Mississippi River, data consumers can't necessarily assume these tag values. Tidal waters can cause strong currents that put paddlers in danger, while a stream with no water is impossible to paddle.

4. Tag watercraft access

Main article: Key:canoe

Add the canoe=* tag to all segments of the waterways for which you know the paddleability. This is the access tag for canoes and kayaks; it does not necessarily imply access for other types of paddlecraft. If for some reason kayaks have different access, add the kayak=* tag in addition to canoe=*. The generic boat=* key can be useful in a pinch, but canoe=* gives data consumers greater confidence that paddle access has been reviewed. See the Key:canoe page for possible values and detailed instructions.

At dams and weirs, look for upstream buoys or markers demarcating the safe paddle zone. If no floating barrier is visible, select a point safely upstream of the dam. Split the waterway here and tag the segment directly above the dam as canoe=no. Tag segments going through or over dams as canoe=no. Most dams have dangerous churns at their downstream outlet, so tag a short segment below the dam as canoe=no as well.

Add the oneway:canoe=* tag to specify if upstream travel is allowed and possible on waterway segments. The oneway:boat=* tag may work as well, but canoes have a different capacity to travel upstream than say, motorboats. The oneway=* tag alone is ambiguous since it may be used to indicate the waterway's flow direction.

If known, it's helpful to add access tags for other types of marine traffic, such as motorboat=*, sailboat=*, and ship=*. These tags give paddlers a heads up about collision risk and potential wake.

5. Put-ins and take-outs

Add a node along the shoreline at each put-in and take-out location. If the put-in has a purpose built ramp, tag the node as leisure=slipway. Otherwise, tag it as waterway=access_point. Add canoe=* to indicate the allowed access for launching canoes and kayaks. Add trailer=* to indicate if boats can be launched from a vehicular trailer.

Connect the put-in to the highway network using the appropriate highway=* tag. Add portage=* to this way. Also connect the put-in to the waterway network using a waterway=link feature. Add canoe=* to this way using the access of the water body, not the put-in.

Add as many details as possible to the put-in. Some useful tags are name=*, informal=*, operator=*, parking=*, fee=*, tidal=*, camping=*, and toilets=*.

6. Portages

Main article: Key:portage

Canoe portages, or carries, are places where paddlers need to haul their boats and gear over land. Typically this is to get between waterways, or to get around obstructions like dams, waterfalls, or rapids.

We leverage the OpenStreetMap road and path network to map portages. Start by mapping all parts of the portage as ways with the appropriate highway=* tag. Then add the relevant portage=* tag to indicate these paths are part of a portage. This is the access tag for a person hauling a boat. See the Key:portage page for possible values and detailed instructions. If known, add hand_cart=* to indicate which sections of the portage allow for rolling boats on wheels.

For a complex portage with lots of segments, it can be helpful to group them all together into a relation tagged with type=route and route=portage. This indicates to others mappers to keep the segments connected in an uninterrupted string.

7. Route relations

Main article: Tag:route=canoe

Once you've added all the components of the paddle infrastructure, you can add any designated water trail as a route relation. Starting and ending at access points, add the relevant waterways and portages to a new relation tagged type=route and route=canoe.

Include only segments that have a canoe=* or portage=* tag with an allowed access value. Omit any gaps in paddleability from the relation; do not add spurious segments just to make a trail seem "complete." If you don't like gapped route relations, you can add a route for each section and connect them in a superroute.

Be sure to add the name=*, operator=*, source=*, and website=* tags to help others verify the route and keep it up-to-date.

8. Extra credit

Congrats, you've mapped the water trail! But there are always more details you can add if you like:

Special cases

Whitewater

Whitewater paddling routes are a subclass of water trails, and use all the same tags. However, pay particular attention to rapids and their portages.

Make sure every segment of river has a rapids=* tag. All rapids should be tagged with their difficulty grade as assessed by an expert whitewater paddler. Use canoe=no for rapids tagged rapids=X, and at least canoe=discouraged for rapids tagged rapids=6. Use source:rapids=* to indicate the source. Use canoe:description=* to give any tips on how to traverse the rapid. Add oneway:canoe=yes to any river segments with strong currents or rapids that preclude upstream travel.

Map all available portage and scouting routes for whitewater rapids. Paddlers need to be able to asses the conditions of any large rapid before attempting it, and to be able to bypass if it needed. Good viewpoints for scouting can be tagged as tourism=viewpoint.

Open water

Wind, weather, and lightning are major dangers to paddlers on open water. The risk increases with the size of the water body and the paddler's distance from shore. On small water bodies such as ponds, it is fine to route paddlers down the feature's centerline. On larger water bodies this could put paddlers miles from shore with few rescue options in case of emergency. Not all boats are built for this use case.

sea_kayak=* is the access tag for seaworthy paddlecraft. If a route puts paddlers far from shore, but is still worth mapping, add sea_kayak=yes plus canoe=no or canoe=discouraged. Consider adding motorboat=* and sailboat=* access tags, as some sea kayak have motors or sails to supplement paddling.

On large water bodies, paddlers will often stick to the shoreline to avoid wide open water. We can add shoreline paddle routes with waterway=fairway. The alignment of these routes is somewhat subjective; generally, keep them as close to the shore as is reasonable, yet beyond the reach of breaking waves. Example access tagging is canoe=yes plus sea_kayak=designated.