OT- Stream gauging

Lemming

Member
Join Date
Oct 2004
Location
PalmerstonNorth
Posts
332
We are working on a project where an extracted flow to the local WTP is prior to a couple of small dams. The requirement is to maintain a residual flow over the dam of 30 l/s. The nominated sub for that is a hydrological company, who derives the flow by measuring the level on the upstream portion of the dam, then gauges the resultant flow downstream. They generate a rating table based on several vists, which is used to generate the compliant flow. This is updated 4 x a year, so is costly thing to maintain.

We have to slave this value back to the WTP Scada, so have the same hydrostatic loop into the local PLC, and have to apply the same rating table 4 x a year...

Where I have a query is both dams have engineered weirs, and I have argued that all that is really necessary is to calibrate the hydrostatic datum to the weir crest, and apply the calc?? On top of this the method of proving accuracy is to check the level, and make sure there isn't a dead sheep blocking the flow etc...

The response is pretty much the stream gauging is more accurate.. I cant understand this at all. Has anyone any experience with river gauging??, and can explain....
 
I'm not a hydrologist but I question that the stream gauging is more accurate. Weirs have been used for flow measurement for centuries, and the behavior is well documented. Here is just one reference:

http://www.engineeringtoolbox.com/weirs-flow-rate-d_592.html

I always get a twitch when the response to a question is "We've always done it that way." That is in essence what you are being told. It seems to me that stream gauging is a fallback technique for waters that don't have any other technique available.
 

Similar Topics

Hi All I have a very simple logic with some light sensors and RFID reader, which are providing start and stop events for capturing some short...
Replies
10
Views
2,707
So I have a PVP7 with keypad and a trend screen setup. I started fumbling around with buttons and managed to move the trend forward and backward...
Replies
0
Views
932
I have a branch circuit with the following motor and drive: Motor 1.1hp 480VAC VFD 1.5kW Normal Duty 2.0hp NEC 430 seems to suggest that I...
Replies
19
Views
4,766
Hi ! i need to connect 2 plcs . S5 Siemens to > Unisream of unitronics . my idea is to do RS232 by the I/O . Meaning to use 1 output from the...
Replies
7
Views
2,116
We have a pump station that is being operated by the UniStream Series of Controller from Unitronics. These have the ability to communicate via...
Replies
6
Views
4,115
Back
Top Bottom