HydroResearch

You are here: Home » Dam Monitoring » Embankment » Hylte
Saturday, 21 Oct 2017

Hylte

E-mail Print PDF

Installation

Optical fibre cables were installed in late 2002 by the dam owner (EON Vattenkraft AB). The cable is placed at a depth of between 0.8 and 1m, all along the dam toe, close to or just below the ground water level. The purpose of this installation is primarily to identify areas with higher seepage, or increasing seepage, but also try to estimate the seepage flow.

 

Result

Seven measurements have been performed since 2003. Five of these have been done just for a few days, while two longer periods were measured during winter 2003-2004 and summer 2005. A Sentinel DTS system was installed in June 2006 for permanent monitoring.

 

The sections where the fastest cooling occurs during the winter period are observed at chainage 50, 90, 145, and 190m. These areas also correspond to those where the temperature is highest in the summer, which can be explained by higher seepage.

Seepage Evaluation

The measurements can also be compared with calculated temperature for different seepage flow rates using the software DamTemp. The seepage flow through the Hylte dam was evaluated from the measured temperatures in two different ways. The first method calculates the maximum measured temperature difference during the measuring period. The seepage flow rate can then be estimated. The other method is based on the measured trend from the long term measurements in 2003/2004. The two methods give a similar flow varying between 5 and 25x10-6m3/s,m, as showed in the figure.