https://openstreetmap.org/copyright | https://openstreetmap.org |
Copyright OpenStreetMap and contributors, under an open license |
https://openstreetmap.org/copyright | https://openstreetmap.org |
Copyright OpenStreetMap and contributors, under an open license |
The pond is visible on OS OpenData - looks like the whole area could do with a survey and a tidy up
here's a trace of the river http://www.openstreetmap.org/user/extua/traces/1651211
Thank you extrua it looks very useful though I've yet to put it into editor to check if it relates.
Can you canoe survey the river part running past St. Clements (
http://www.openstreetmap.org/way/1881438#map=17/51.75124/-1.24141
) that is over hung with trees and some building features that have the river going under. I stuggle to map this from air alignments, after ground surveying from the medow. There are some low pipes at the north end but I think a canoe could make it though to the punting station by the slipway to the highstreet?
When I looked at this in recent years it seems to be a time varying forest track reinstated by the gardners with mowers and strimmers.
It was about a year or so back in the summertime much more definned than before with extra seating and artworks dotted about the wood. Low grade tracks and open brackenscape (under trees) allow pedestrians to go west for most of this path.
The cherwell in places, like originaly near the A420 bridge (to the south), suffered from reduced with, like meny rivers in osm, as they were originaly mapped airialy and measured up to the canopy line of over hangging trees (even comercialy I think to in some spots) the trees on the Angle and Greyhound Meadow (to the south are able to compleately cover the very wide river on the eastern reaches.
The track shown says its a incompleate diagramatic standin for the path, as I couldn't plot it accuratly at all as its not vissable from above tree hight in aligning sources.
I think the path goes off to the bridges on the unpolted bit missing near Bat willow Meadow and sort of links with other bridges (one shown today) to Addison's Walk {
https://www.openstreetmap.org/way/244340319/history#map=19/51.75424/-1.24011&layers=N
}
Unfortunately the river was flowing really fast this past month and we've moved onto the canal for the moment. It's a real struggle to move about when there's so much force in the water, and surveying gets difficult because on the cherwell it breaks its banks in some areas and you have to guess where the 'real' riverbank is.
I won't go up the cherwell for at least another few months, but next time I do I'll try to bring along a phone. When it's sunny and the river is calm and we'll have plenty of time to map it out.
oh also, after the floods in 2014 the part above King's Mill weir was all cleared and dredged, as a result the river became much wider (and more navigable). Since then a few trees have fallen across the river, causing blockages at the island below king's mill, and on the island above parson's pleasure. Weeds and shallow banks have reappeared, it's particularly bad on the wiggly channel to the left of the university boathouses where a sand bank has turned into a proper piece of land, and several fallen trees have caused a buildup of silt and debris. Basically the geography of the cherwell is quite variable compared to the Thames.
Thank you for the infomation. I notoiced it goes up and down a lot too I1/2 a meter in the last week it dropped and no floods down here this season yet. It feels odd to me not do rivers with multi-hights like estries. I'm sure that contributed to the new buildings going on flood plans (That cheap victorian slum like development on the canal and stream side at osney is included. Why the built them so low compared to near the donnington bride Iffley rd side I guess it must be makeing the cheap back then...
Here are some GPS traces I recorded last month
http://www.openstreetmap.org/user/extua/traces/2147567
http://www.openstreetmap.org/user/extua/traces/2129883
thank you extua That will be really useful I'll crank up a system very soon and try to incorpate the measurements. Is there an offset from the bank when became shallow or do I take the measurements as "exact" water lines?
"exact as a contor for the day is representative for a slopeing sided channel.
I tried using extra's canoe tacks to amend the river bankss but I found it lot tougher than I first thought mainly as I have no knowledge of where the canoe was in relation to the bank or how the bak looked from inside the canoe. so it was bit to much guess work.
https://www.openstreetmap.org/changeset/38762251
How does it work for you extua?
Does this note need to be open?
Will the 2023 Ordnance Survey map be useful?