<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body text="#000000" bgcolor="#FFFFFF">
<div class="moz-cite-prefix">On 03/04/18 23:22, Martin Koppenhoefer
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:56AF4CB9-9120-4980-8571-9680BF6A4116@gmail.com">
<meta http-equiv="content-type" content="text/html; charset=utf-8">
<br>
<br>
<div id="AppleMailSignature">sent from a phone</div>
<div><br>
On 2. Apr 2018, at 23:40, Graeme Fitzpatrick <<a
href="mailto:graemefitz1@gmail.com" moz-do-not-send="true">graemefitz1@gmail.com</a>>
wrote:<br>
<br>
</div>
<blockquote type="cite">
<div>
<div>Should it continue more or less straight, following the
line of the beach, across the mouth of the estuary; or
should it follow the estuary / river bank for an
undetermined distance inland?</div>
</div>
</blockquote>
<br>
<div><br>
</div>
<div>the coastline should represent the limit of the sea, in case
of a river flowing in, people look at the level of salt in the
water and whether the level of the river is influenced by tides
(afaik), for example here you can see a coastline at a “river”:</div>
<div><br>
</div>
<div><a
href="https://www.openstreetmap.org/way/88960837#map=9/53.6926/9.3947"
moz-do-not-send="true">https://www.openstreetmap.org/way/88960837#map=9/53.6926/9.3947</a></div>
</blockquote>
<br>
River flows can be extremely different from one season to the next
in some parts of the world. <br>
Consider the tropics where the major seasons are described as 'wet'
and 'dry', river levels can change by 5 meters between the seasons.
<br>
<br>
In other places the tide can influence river levels for many
kilometres inland. <br>
<br>
In both those cases the salt levels will vary from one extreme to
another. <br>
<br>
Possibly best to take the minimum intrusion of the sea into the
river? Maybe not for some though - the rate of flow will have fresh
water going out into what most would call the sea! <br>
<br>
Where this detail is unknown then Graeme's approach of a straight
line across the mouth of the river can be used to minimise work and
signify the lack of information or the conflict for the area. <br>
</body>
</html>