The Effect of Adjustable Outflow on the Fluctuations in the Level of Surface and Ground Water

Abstract

This paper aims to analyze the variability of the surface and ground water levels in Ambona peatlands. The depth at which the ground water table occurred was studied with reference to the adopted land drainage standards. The studies were carried out in 2009/10–2015/16 for natural and regulated water outflows. The analysis of annual total precipitation suggests that in the analyzed period some years were very wet (2009/10 and 2013/14), some were wet (2010/11, 2012/13 and 2015/16), one year was dry (2014/15) and one year was normal (2011/12). The 7-year average seasonal precipitation amounted to 598 mm, which was 71 mm higher than the average precipitation recorded in 30 years. The level of water in the river under adjustable outflow conditions ranged from 55 to 77 cm. The level of water under natural outflow ranged from 18 to 49 cm. In the area with adjustable outflow, the average draining depth was 47 cm. In the remaining area, not covered by the irrigation system, the draining depth was 64 cm. Additionally, the dynamics of variance in the water level under natural outflow conditions was clearly higher.

Keywords

• precipitation
• surface water
• ground water
• adjustable outflow