My Account: Log In | Join | Renew
Search
Author
Title
Vol.
Issue
Year
1st Page

Abstract

  VZJ Banner

This article in VZJ

  1. Vol. 10 No. 1, p. 110-124
    OPEN ACCESS
     
    Received: Feb 5, 2010
    Published: Feb, 2011


    * Corresponding author(s): jbki@geus.dk
 View
 Download
 Alerts
 Permissions

doi:10.2136/vzj2010.0017

Spatial Distribution of Seepage at a Flow-Through Lake: Lake Hampen, Western Denmark

  1. Jacob Kidmose *b,
  2. Peter Engesgaarda,
  3. Bertel Nilssonb,
  4. Troels Laierb and
  5. Majken C. Loomsa
  1. b Geological Survey of Denmark and Greenland, Ostervoldgade 13, 1350 KBH K, Denmark
    a Dep. of Geography and Geology, Univ. of Copenhagen, Ostervoldgade 13, 1350 KBH K, Denmark

Abstract

The spatial distribution of seepage at a flow-through lake in western Denmark was investigated at multiple scales with integrated use of a seepage meter, lake–groundwater gradients, stable isotope fractionation (δ18O), chlorofluorocarbon (CFC) apparent ages, land-based and off-shore geophysical surveys, and lake bed coring. Results were compared with a three-dimensional catchment-scale groundwater flow model using the MODFLOW and LAK3 codes for simulating lake–groundwater interaction. Seepage meter and model results of discharging groundwater to the lake compared well, if direct seepage measurements from near shore were combined with measurements from deeper parts of the lake. Discharge rates up to 9.1 × 10−7 m s−1 were found. Ground-penetrating radar used to map the lake bed sediments proved very effective in recognizing low- and high-permeability areas but also in understanding the complex recharge pattern of the lake and relating these to the geologic history of the lake. Recharge of the surrounding aquifer by lake water occurs offshore in a narrow zone, as measured from lake–groundwater gradients. A 33-m-deep δ18O profile at the recharge side shows a lake δ18O plume at depths that corroborates the interpretation of lake water recharging offshore and moving down gradient. Inclusion of lake bed heterogeneity in the model improved the comparison of simulated and observed discharge to the lake. The apparent age of the discharging groundwater to the lake was determined by CFCs, resulting in ages between 3 and 36 yr with an average of 16 yr. The simulated average groundwater age was 13.2 yr.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © 2011. Soil Science SocietySoil Science Society of America

Facebook   Twitter