Steady-state water table height estimations with an improved pseudo-two-dimensional Dupuit-Forchheimer type model

Mass movements are quite common in the Northern Andes and constitute one of the major hazards in the region. In particular, along valley flanks where the city of Medellin (Colombia) is located, rainfall is the main trigger of these phenomena, but little is understood about how water in the soil and subsoil behaves. In this study, we show data from some basic soil hydrology measurements and conventional geophysical surveys within a ~4 ha experimental plot that is experiencing soil creep. The seasonally wet study site has an average slope gradient of 33%, and its surface geology consists of a series of older deposits of debris flows. Our measurements show a low surface runoff, which ranges from 4 to 11% of the rainfall; infiltration is 89–96% of the rainfall, and 15–33% corresponds to drainage water at shallow levels in the soil (20–50 cm); piezometric measurements reveal a mostly steady-state water table. About 14–54% of the rainfall becomes subsurface flow within the first ~1–2 m below the surface. Geoelectrical and seismic surveys suggest small temporal changes in the properties of materials shallower than 2 m, consistent with the steady-state water table and the permanent and high subsurface flow. These geophysical surveys also indicate the presence of a major discontinuity at ~4–6 m below the surface, which we interpret as the limit between different prior debris flows.

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Two Dimensional Heat Transfer in Porous Media with Steady-State Water Flow

Soil Science Society of America Journal ◽

10.2136/sssaj1971.03615995003500020015x ◽

1971 ◽

Vol 35 (2) ◽

pp. 209-214 ◽

Cited By ~ 2

Author(s):

K. T. Erh ◽

D. R. Nielsen ◽

J. W. Biggar

Keyword(s):

Heat Transfer ◽

Porous Media ◽

Steady State ◽

Water Flow ◽

Two Dimensional ◽

State Water

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Some properties of Dagan’s method for drain spacing determination in marshy - gley soil

Journal of Agricultural Sciences Belgrade ◽

10.2298/jas0301069d ◽

2003 ◽

Vol 48 (1) ◽

pp. 69-75 ◽

Cited By ~ 1

Author(s):

Nevenka Djurovic ◽

Ruzica Stricevic

Keyword(s):

Steady State ◽

Linear Function ◽

Water Flow ◽

Water Table ◽

Drainage System ◽

Water Table Depth ◽

Flow Conditions ◽

Drain Spacing ◽

State Water ◽

Dry Out

Dagan?s method as well as Kirkham?s one belong to the group of methods for drain spacing determination in steady state water flow conditions. Both methods are based on the assumption that drainage spacing (L) is linear function of water table depth and drainage discharge (h/q). The only difference can be distinguished in the values of coefficients. To dry out eugley type of soil, drain spacing is better determined by Dagan?s method in all treatments, as compared with Kirkham?s one. Advantage of this method is especially marked on the drainage system with narrower drain spacing.

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Some properties of Kirkham’s method for drain spacing determination in marshy - gley soil

Journal of Agricultural Sciences Belgrade ◽

10.2298/jas0301059d ◽

2003 ◽

Vol 48 (1) ◽

pp. 59-67

Author(s):

Nevenka Djurovic ◽

Ruzica Stricevic

Keyword(s):

Steady State ◽

Ground Water ◽

Water Flow ◽

Water Table ◽

Soil Type ◽

Water Discharge ◽

Water Table Depth ◽

Drain Spacing ◽

State Water ◽

Drainage Field

The aim of this work is to present some peculiarity of Kirkham?s method applied in drain spacing determination in steady state water flow in eugley soil type. The analysis was based on data obtained by measuring water discharge from drains and water table depth. Measurements was carried out on drainage field with drain spacing of 10 m, 20 m and 30 m, representing drainage treatments I, II and III, respectively. The estimation of drain spacing is moved to lower value in all treatments. The results of analysis show meaningful limitation of method, especially in the treatments with wider drain spacing as well as in the cases of deeper ground water.

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