Karst and Cave RSS news feed Like us on Facebook! follow us on Twitter!
Community news

Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That loam is calcareous clay [16].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

What is Karstbase?

Search KARSTBASE:

keyword
author

Browse Speleogenesis Issues:

KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
Engineering challenges in Karst, Stevanović, Zoran; Milanović, Petar
See all featured articles
Featured articles from other Geoscience Journals
Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
See all featured articles from other geoscience journals

Search in KarstBase

Your search for drainage network (Keyword) returned 31 results for the whole karstbase:
Showing 1 to 15 of 31
Significance and origin of very large regulating power of some karst aquifers in the Middle East. Implication on karst aquifer classification, , Elhakim M, Bakalowicz M,
SummaryKarst aquifers are the main groundwater resource in Lebanon as well as in most Mediterranean countries. Most of them are not exploited in a sustainable way, partly because their characteristics remain unknown. Karst aquifers are so complex that the assessment of their resource and their exploitable storage requires an analysis of their whole functioning, particularly by analysing the spring hydrograph. Among all various methods, the method proposed by Mangin aims to characterize at the same time the recharge conditions and the storage and recession of the saturated zone by analyzing the spring hydrograph. This method defines two parameters, the infiltration delay i, and the regulating power k which are the roots of a classification of karst systems. This classification makes the distinction between karst and porous aquifers considering the value of the regulating power. k is assumed to be lower than 0.5 in karst, and between 0.5 and 1 for all other aquifers, 1 being the upper limit.The study of karst aquifers in Lebanon shows values of k > 0.5, and even 1; former data from the literature show that other karst springs in Middle East have comparable characteristics. In fact, what is not considered by Mangin and others, k is equivalent to a mean residence time in years of water in the saturated zone. So long residence times are normally observed in poorly karstified aquifers, or containing abandoned, not functioning karstification. The geological framework in which the studied springs are located in fact shows that these aquifers have been subject to a long, complex evolution, as a consequence of the base level rising. This rising produced the flooding of the successive karst drainage network, which does not really function anymore and provides a large storage capacity to the aquifer. The very interesting properties of these aquifers make them prime targets for fulfilling the increasing needs of water

The Aggitis karst system, Eastern Macedonia, Greece: Hydrologic functioning and development of the karst structure, , Novel Jean Paul, Dimadi Agoro, Zervopoulou Anna, Bakalowicz Michel,
SummaryThe Aggitis karst system developed in the marbles of the Rhodope massif. The conditions of the development of its karst drainage network are determined from the geological and geomorphologic settings by means of a microstructural analysis, following Eraso's method. This analysis shows that the karst conduit network intensely developed in the western part of the mountain Falakro where the majority of the open fractures oriented in the same direction as the hydraulic gradient, while the two directions are perpendicular in its eastern part drained by the spring of Drama.The behaviour of the system was analysed by means of hydrodynamic and water geochemical techniques. Despite the extension of the cave system and of the favourable development conditions of conduits, the functioning appears complex, with a significant storage, and a slow infiltration as well as an easy drainage. On the contrary the Drama karst system, characterised by a low variability in its hydrological and geochemical characteristics does not show any karst functioning.In the Aggitis karst system the initial groundwater flow conditions in combination with the aperture planes of which the directions are in agreement with the hydraulic gradient, favoured the rapid development of a drainage network system. The recharge from a large surface catchment area on non-karstic rocks, through swallow holes in a wide polje contributed to increase the groundwater flow through the karst part of the system, facilitating the development of the conduits

Rpartition quantitative des phnomnes karstiques super-ficiels et souterrains en fonction de la lithologie sur le Causse Comtal (Aveyron, Fr .), 1983, Dodge, D.
QUANTITATIVE DISTRIBUTION OF THE SURFICIAL AND UNDERGROUND KARSTIC PHENOMENA ACCORDING TO LITHOLOGY ON THE CAUSSE COMTAL (AVEYRON, FRANCE) - The quantitative distribution of karst phenomena (dolines, karren, dry valleys, springs, sinkholes and caves) in the Causse Comtal aquifers is analysed. This distribution is dependent on lithology, topography, tectonics, and permeability of the aquifer layers and relative importance of underground drainage networks. The part played by each of these factors in the development of the observed phenomena is discussed. The relationship between superficial and deep karst features is examined.

Hydrology of autogenic percolation systems in some tropical karst outcrops, West Malaysia, 1983, Crowther J,
This paper reports on the flow regimes of underground seepages in three tower-karst outcrops and in the Setul Boundary Range, West Malaysia. Groundwater movement in the tower-karst hills, which comprise very pure, massive marbles, is confined to vertical and subvertical joints. Although flow is primarily diffuse and the discharges of the majority of seepages correlate most closely with rainfall in antecedent periods of 1-16 days or more, some stormflow occurs along conduits in the upper parts of these aquifers. Many of these conduits appear to peter out at depth into tight rock fractures, thereby forming funnel-shaped underground reservoirs which serve to moderate discharge variations. In contrast, the limestones of the Setul Boundary Range are less pure and retain much of their original bedding. The presence of near-horizontal bedding plane fractures favours lateral groundwater movement and the development of integrated drainage networks within the rock. Compared with the tower-karst caves, seepage rates are generally higher and more responsive to short-term variations in rainfall. The marked difference in topography between the tower-karst hills and the Setul Boundary Range is largely attributable to the contrasted geohydrological properties of the limestones

General characteristics of the landforms in the Alps and Julian Prealps and in Trieste Karst., 1989, Vaia Franco
The morphology of the Julian Alps and Prealps and of the Triestian Karst are here shortly described; the structures, which defined its origin and development, are also considered. We can notice some cliffs which follow one another from the State boundary to the Adriatic sea; they are made up by lithologic successions, which repeat themselves according to the latitude. Anyway we recognize a general outcropping of rock masses which are decreasing little by little southward as regards the altitude, the age and than the erodibility. There are some differences between the western (Carnian) and the eastern (Julian) bend of the regional mounts according not only to the latitude but to the longitude, because of the lithology. In fact, the Julian mountains often look like the Dolomities in the northern zone. The southern ones, particularly near the high alluvial plain, are rounded and gently dipping. The drainage networks are quite different too. In the upper zone it is a trellis net, in the lower one is locally a trellis net and than it becomes a dendritic system. The glacial erosion follows the same principle too, coming southward along the main and the subordined valley cuts. At last, the Karst morphology shows itself strongly conditioned by the structural scheme as well as by the lateral lithologic changes. It comes out an anisotropic whole of surface forms and of subsurface ones, clearly referred to those reasons. The whole area here described shows moreover a high evolutive dynamics, connected with the recent tectonic phases.

Signification godynamique des rseaux karstiques tags du canyon de Baudinard (moyennes gorges du Verdon, 1992, Blanc, J. J.
GEODYNAMIC SIGNIFICATION OF LEVELLED KARSTIC NETWORKS IN THE BAUDINARD CANYON (VERDON CANYON, FRANCE) - An intense speleogenic activity can be observed in the Baudinard canyon: some levelled systems in relation to the lowering karstic water-table linked to the formation of the canyon, during Messinian, Pliocene and Quaternary periods. An active tectonic framework shows many deformations of the ante-vindobonian surface during the plio-quaternary burrowing canyon phases. Azimuth gallery direction analysis reveals several sorts of drainage network: linear, smoothed with loops, labyrinths and drainage-confluences. Networks are induced by local and successive tectonic actions. The gallery wall deformations are strongly marked by the shrinking stresses and interstrata shearing.

IMPACT OF AN EXCEPTIONAL STORM EPISODE ON THE FUNCTIONING OF KARST SYSTEM - THE CASE OF THE 22/9/92 STORM AT VAISON-LA-ROMAINE (VAUCLUSE, FRANCE), 1995, Lastennet R. , Mudry J. ,
Karstification is a slow geodynamical process, controlled by the interaction between dissolution kinetics and flow dynamics. Moreover, mechanisms of network clogging by calcite precipitation or non-soluble clay accumulation are slow and continuous phenomena. This evolution of a karst system can be widely modified during exceptional rainfall episodes, such as the 22/09/92 storm (> 300 mm) near Vaison-la-Romaine. Such an impulse can modify the hydraulical behaviour of a massif, by unclogging the outlets of the saturated zone or the drainage network of the aquifer, and change hydrodynamical features of a spring (storage capacity etc.). This phenomenon has been demonstrated in a north Vaucluse karst aquifer whose recession coefficient has increased 7-fold and stored volume divided by 6

Numerical multisource and multiscale imagery in the study of the topographic surface. Hydrogeological application in a karstic environment: Verneuil-sur-Avre (Perche, France), 1996, Sykioti O. , Deffontaines B. , Chorowicz J. , Obert D. , Demarsily G. , Lauverjat J. , Carvalho J. ,
We propose a new method revealing geological structures and their possible relationships with water percolation. It is based on a combination of (1) numerical analysis of the topography (satellite imagery Landsat TM, HCMM, SAR-ERS1; digital elevation model and derived data: drainage network, slope map, summit level surfaces...); (2) classic geological approach (field work, geological mapping, gravimetry); and (3) hydrogeological approach (piezometric map, tracer experiments). The superimposition of these data into a geocoded data base leads to the identification and the location of morphostructures (synthetic structural map). Field data and tracer experiments confirm the validity of the results. We propose to take into consideration the present day stress regime in order to define main orientations of open fractures. In conclusion, this method provides structural information allowing a better understanding of geometry in karstic aquifers

Geomorphological evidence for anti-Apennine faults in the Umbro-Marchean Apennines and in the peri-Adriatic basin, Italy, 1996, Coltorti M, Farabollini P, Gentili B, Pambianchi G,
The Apennines are a relatively recent mountain chain which has been affected by uplift movements since the Upper Pliocene. In fact the remnants of an “erosional surface”, reduced close to base level, is preserved at the top of the relief. There is no general agreement on the geodynamic stress field and mechanisms which are creating the chain. However, it is largely accepted that uplift occurred together with the activation, on the western side of the chain, of extensive faults, oriented in the Apennine direction (NW-SE), which have been linked to the opening of the Tyrrhenian sea. A great debate is going on about the presence and significance of anti-Apennine faults (NE-SW) which have been observed by some authors but completely denied by others.The main evidence is represented by[ (1) block faulting of the remnants of the “erosional surface”. Along the Marchean Ridge, more elevated relief, delimiting relatively depressed areas, was created in correspondence with the Sibillini Mts. and Mt. S. Vicino. Similar evidence has been found in the Umbro-Marchean Ridge. Locally more than 1500 metres of displacement have been observed between more and less uplifted remnants. (2) Block faulting of fan deltas and related beaches, of Sicilian to Crotonian age, with more elevated sediments preserved between the Tronto and Tenna rivers and between the Musone and Esino rivers. Maximum displacement along a transect parallel to the coast is 200 metres. (3) fault-scarps affecting the Middle Pleistocene river terraces, as observed along the Esino, the Tronto, the Chienti and the Tenna river valleys. Maximum displacements are in the order of 50 metres. (4) Faulting of horizontal karst galleries and reorientation of the cave network, as in the Frasassi Gorge. Maximum displacements are about 100 metres. (5) Captures and alignments in the drainage network of the main river courses. (6) Large-scale gravitational movements, as in the Ancona landslide, and along the Chienti and Esino rivers.Their activation occurred in most cases after the Lower Pleistocene and although their displacements may be of relatively limited extent, dispite their recent activity, they played a major role in the modelling of the landscape. These faults display transtensive, extensional and trascurrent movements. Apart from the controversial geodynamic significance of these faults, from a geomorphological point of view they must be considered transverse elements of the stress field from blocks more or less uplifted along the Apennine chain.The importance and timing of activity of these faults in the Quaternary geomorphological evolution of the Umbria-Marchean Apennines is demonstrated using evidence usually underestimated by structural geologists, which can contribute to a debate based on a multidisciplinary approach

The Eastern boundary of the giant karst of Vaucluse in relation to the lineament-fault of Aix-en-Provence (Provence, Alps, Cote d'Azur Region, France), 1997, Rousset C. ,
In the Saint-Donat area, along the Mardaric stream, a tributary of the mid Durance, water losses associated with temporary springs can be observed. These springs run off overflows of the Vaucluse karstic system. Their impluvium extends over the limestones of the eastern part of the Montagne de Lure; this karstic area contributes, with the runoff entering into the losses, to the underground flows of the Fontaine de Vaucluse. As it rose eastwards, the drainage network of this giant karst was halted by the faults of the Aix-en-Provence lineament, in which very strongly deepening marls form a barrier around the aquifer. This is new evidence of the part played by the Hercynian-inherited lineament framework in limiting giant karsts of the Vaucluse-type, as is the case for the Alpine carbonate platforms in which they have developed

Relations between the structure of storage and the transport of chemical compounds in karstic aquifers, 1997, Vaute L. , Drogue C. , Garrelly L. , Ghelfenstein M. ,
Study of the movement of chemical compounds naturally present in the water, or which result from pollution, are examined according to the reservoir structure in karstic aquifers. Structure is represented by a simple geometrical model; slow Row takes place in blocks with a network of low-permeability cracks. The blocks are separated by highly permeable karstic conduits that allow rapid flow, and these form the aquifer drainage system. The karat studied covers 110 km(2). It is fed by an interrupted stream draining a 35 km(2) non-karstic basin, contaminated at the entry to the karst by effluents from a sewage treatment station. The underground water reappears as a resurgence with an annual average flow of approximately 1 m(3) s(-1), after an apparent underground course of 8 km in the karst. Several local sources of pollution (effluent from septic tanks) contaminate the underground water during its course. Sixteen measurement operations were performed at 12 water points, between the interrupted stream and the spring. Some sampling points were at drains, and others were in the low-permeability fissured blocks. Comparison at each point of the concentrations of 14 chemical compounds gave the following results: when pollutant discharge occurs in a permeable zone, movement is rapid in the drainage network formed by the karstic conduits, and does not reach the less permeable fissured blocks which are thus protected; however, if discharge is in a low-permeability zone, the flow does not allow rapid movement of the polluted water, and this increases the pollutant concentration at the discharge, This simple pattern can be upset by a reversal of the apparent piezometric gradient between a block and a conduit during Floods or pumping; this may reverse flow directions and hence modify the movement of contaminants. The study made it possible to site five boreholes whose positions in the karstic structure were unknown, showing the interest of such an approach for the forecasting of the impact of potential pollution.

Application of morphometric relationships to active drainage Networks within the Mammoth Cave karst aquifer., 1997, Glennon J. A. , Groves C.

Oxidation of organic matter in a karstic hydrologic unit supplied through stream sinks (Loiret, France), 1998, Alberic P, Lepiller M,
The aim of this paper is to appraise the ability of the oxidation of riverine organic matter in the control of limestone dissolution, in a karst network. Biogeochemical processes during infiltration of river water into an alluvial aquifer have already been described for an average flow velocity of 4-5 m d(-1) (Jacobs, L. A., von Gunten, H. R., Keil, R, and Kuslys, M. (1988) Geochemical changes along a river-groundwater infiltration flow path: Glattfelden, Switzerland. Geochim. Cosmochim. Acta 52, 2693-2706; Von Gunten, H. R., Karametaxas, G., Krahenbuhl, U., Kuslys, M., Giovanoli R., Hoehn E. and Keil R. (1991) Seasonal biogeochemical cycles in riverborne groundwater. Geochim. Cosmochim. Acta 55, 3597-3609; Bourg, A. C. M. and Bertin, C. (1993) Quantitative appraisal of biogeochemical chemical processes during the infiltration of river water into an alluvial aquifer. Environ. Sci. Technol. 27, 661-666). Karstic drainage networks, such as in the River Loire-Val d'Orleans hydrologic system (Fig. 1), make possible flow velocities up to 200 m h(-1 a) and provide convenient access to different water samples several tens of km apart, at both extremities of the hydrologic unit (Chery, J.-L. (1983) Etude hydrochimique d'un aquifere karstique alimente par perte de cours d'eau (la Loire): Le systeme des calcaires de Beauce sous le val d'Orleans. These, Universite d'Orleans; Livrozet, E. (1984) Influence des apports de la Loire sur la qualite bacteriologique et chimique de l'aquifere karstique du val d'Orleans. These, Universite d'Orleans). Recharge of the karstic aquifer occurs principally from influent waters from stream sinks, either through coarse alluvial deposits or directly from outcrops of the regional limestone bedrock (Calcaires de Beauce). Recharge by seepage waters From the local catchment basin is small (Zunino, C., Bonnet, M. and Lelong, F. (1980) Le Val d'Orleans: un exemple d'aquifere a alimentation laterale. C. R. somm. Soc. Geol. Fr. 5, 195-199; Gonzalez R. (1992) Etude de l'organisation et evaluation des echanges entre la Loire moyenne et l'aquifere des calcaires de Beauce. These, Universite d'Orleans) and negligible in summer. This karstic hydrologic: system is the largest in France in terms of flow (tens to hundreds of m(3)/s) and provides the main water resource of the city of Orleans. Chemical compositions of influent waters (River Loire) and effluent waters (spring of the river Loiret) were compared, in particular during floods in summer 1992 and 1993 (Figs 2-4). Variation of chloride in the River Loire during the stream rise can be used as an environmental tracer of the underground flow (Fig. 2). Short transit times of about 3 days are detectable (Fig, 2) which are consistent with earlier estimations obtained with chemical tracers (Ref. in Chery, J.-L. (1983) These, Universite d'Orleans). Depending on the hydrological regime of the river, organic carbon discharge ranges between 3-7 and 2-13 mg/l for dissolved and particulate matter respectively (Fig. 3). Eutrophic characteristics and high algal biomasses are found in the River Loire during low water (Lair, N. and Sargos, D. (1993) A 10 year study at four sites of the middle course of the River Loire. I - Patterns of change in hydrological, physical and chemical variables in relation to algal biomass. Hudroecol. Appl. 5, 1-27) together with more organic carbon rich suspended particulate matter than during floods (30-40 C-org % dry weight versus 5-10%). Amounts of total organic carbon and dissolved oxygen (Fig. 3) dramatically decrease during the underground transport, whereas conversely, dissolved calcium, alkalinity and inorganic carbon increase (Fig. 4). Anoxia of outflows map start in April. Dissolution of calcium carbonates along the influent path outweighs closed system calcite equilibrium of inflow river waters (Table 3). The impact of organic matter oxidation on calcite dissolution may be traced by variations of alkalinity and total carbonates in water. Following, Jacobs, L. A., von Gunten, H. R., Keil, R. and Kuslys, M. (1988) Geochemical changes along a river-groundwater infiltration flow path: Glattfelden, Switzerland. Geochim. Cosmochim. Acta 52, 2693-2706), results are shown graphically (Fig. 5). Extent of reactions is controlled by the consumption of dissolved O-2 and nitrate for organic matter oxidation and by the release of Ca2 for calcite dissolution (Table 2). The karstic network is considered to behave like a biological reactor not exchanging with the atmosphere, with steady inhabitant microbial communities (Mariotti A., Landreau A, and Simon B. (1988) N-15 isotope biogeochemisrry and natural denitrification process in groundwater: Application to the chalk aquifer of northern France. Geochim. Cosmochim. Acta 52, 1869-1878; Gounot, A.-M. (1991) Ecologie microbienne des eaux ei des sediments souterrains. Hydrogeologie, 239-248). Thus, energy requirements only are considered, not carbon assimilation. Moreover, there is no necessity to invoke any delay for nitrification enhancement, as observed elsewhere, after waste water discharge into the river (Chesterikoff, A., Garban, B., Billen, G. and Poulin, M. (1992) Inorganic nitrogen dynamics in the River Seine downstream from Paris (France). Biogeochem. 17, 147-164). Main microbial processes are assumed to be aerobic respiration, nitrification and denitrification. Reactions with iron and manganese, real but not quantitatively important, were neglected. Sulphate reduction and methane formation, certainly not active, were not considered. Denitrification, which is suggested by low nitrate and ammonium concentrations and anoxia in the outflow, is known to be rapid enough to be achieved in a short time (Dupain, S. (1992) Denitrification biologique heterotrophe appliquee au traitement des eaux d'alimentation: Conditions de fonclionnement et mise au point d'un procede. These, Universite Claude Bernard, Lyon). Reaction are somewhat arbitrary but conform to general acceptance (Morel, M. M. and Hering, J. G. (1993) Principles and Applications of Aquatic Chemistry. Wiley, New York). Anaerobic ammonium oxidation (Mulder A., van de Graaf, A. A., Robertson, L: A. and Kuenen, J. G. (1995) Anaerobic ammonium oxidation discovered in a denitrifying fluidized bed reactor. FEMS Microbiol. Ecol. 16, 177-184). although possible, was not considered. In fact, C/N ratio of the reactive organic matter has only mild repercussions on the results; i.e. in the same range as the analytical errors for alkalinity and total carbonates. The objective was simply to roughly confront characteristics of outflowing waters and the calculation. Respective roles of aerobes and denitrifiers, for instance, are not certain. Several periods during low water or floods were selected with various ranges for calcium dissolution or nitrate and oxygen concentrations. The result is that in most cases simulation and data are in reasonable accordance (Fig. 5). Amounts of organic matter in River Loire are generally sufficient to sustain the process (Table 3. Particulate organic matter is probably the most reactive. The balance of oxidation of organic matter indicates that about 65 mu g C-org/l.h are oxidized during the transport without much variation with the river regime or organic discharge. It is concluded that limestone dissolution is directly dependent on organic matter oxidation, but variation occurs (7-29 mg CuCO3/l) with the level of bases that can be neutralized in the River Loire water. (C) 1998 Elsevier Science Ltd. All rights reserved

Comparison of stormwater management in a karst terrane in Springfield, Missouri - case histories, 1999, Barner Wl,
Control of stormwater in sinkhole areas of Springfield, MO has involved the utilization of several standard approaches: concrete-lined channels draining into sinkholes; installation of drainage pipes into the sinkhole 'eyes' (swallow holes); filling of sinkholes; elaborate drains or pumps to remove stormwater from one sinkhole and discharging into another drainage basin or sinkhole; and enlargement of swallow holes by excavation to increase drainage capacity. Past planning considerations and standard engineering approaches have resulted in flooding of sinkholes and drainage areas, including residential, industrial and commercial developments. Having recognized the inadequacy of existing designs to control flooding and the need to accommodate increased runoff from future development, the City of Springfield adopted an ordinance (effective 19 June 1989 and modified in 1990 and 1993) in response to public pressure and concerns over flooding in sinkholes and sinkhole drainage areas. Three sites were analyzed to examine the effectiveness of contrasting design approaches to stormwater management. These sites differ in vegetation, on-site/off-site considerations, and types of development proposed. All three sites are located within the East Cherry Street Sinkhole Area. The first site, a wooded tract with unmodified sinkholes was cleared and developed for residential use. Discharge of stormwater was directed into sinkholes, and erosion control consisted of hydro-mulching and sedimentation fences in sinkhole areas. East of this location are two parcels which differ in removal of vegetation and off-site drainage relationships. Stormwater design in these sites was adapted for modifications made to sinkholes during railroad and highway construction several decades earlier. Sediment fencing, hydro-mulching and detention berms augment infiltration, restrict erosion, retard discharge to sinkholes, and incorporate off-site considerations. Ongoing observations of stormwater behavior indicate problems of flooding and sediment control at the western site but minimal disruptions of existing drainage patterns at the eastern sites. Design calculation for the western site show adequate volume retention in sinkholes, but different design approaches were implemented to 'soften' the impact of stormwater discharging into these sinkholes, allowing for minimal disruptions in the natural drainage network. The lack of recognition of sinkholes as integral parts of dynamic hydrologic systems may result in problems with on-site/off-site drainage. Standard engineering designs for stormwater detention are not appropriate for the hydraulic characteristics of the shallow karst drainage network. While runoff estimations are conservative, the design calculations fall short of adequately addressing actual stormwater runoff characteristics. (C) 1999 Elsevier Science B.V. All rights reserved

Drainage-basin-scale geomorphic analysis to determine reference conditions for ecologic restoration--Kissimmee River, Florida, 2000, Warne Andrew G. , Toth Louis A. , White William A. ,
Major controls on the retention, distribution, and discharge of surface water in the historic (precanal) Kissimmee drainage basin and river were investigated to determine reference conditions for ecosystem restoration. Precanal Kissimmee drainage-basin hydrology was largely controlled by landforms derived from relict, coastal ridge, lagoon, and shallow-shelf features; widespread carbonate solution depressions; and a poorly developed fluvial drainage network. Prior to channelization for flood control, the Kissimmee River was a very low gradient, moderately meandering river that flowed from Lake Kissimmee to Lake Okeechobee through the lower drainage basin. We infer that during normal wet seasons, river discharge rapidly exceeded Lake Okeechobee outflow capacity, and excess surface water backed up into the low-gradient Kissimmee River. This backwater effect induced bankfull and peak discharge early in the flood cycle and transformed the flood plain into a shallow aquatic system with both lacustrine and riverine characteristics. The large volumes of surface water retained in the lakes and wetlands of the upper basin maintained overbank flow conditions for several months after peak discharge. Analysis indicates that most of the geomorphic work on the channel and flood plain occurred during the frequently recurring extended periods of overbank discharge and that discharge volume may have been significant in determining channel dimensions. Comparison of hydrogeomorphic relationships with other river systems identified links between geomorphology and hydrology of the precanal Kissimmee River. However, drainage-basin and hydraulic geometry models derived solely from general populations of river systems may produce spurious reference conditions for restoration design criteria

Results 1 to 15 of 31
You probably didn't submit anything to search for