Rivers and Groundwater Quick Review Rivers and Groundwater April 2001 Copyright by Dr. Isiorho

April 2001 Copyright by Dr. Isiorho Surface Water The Hydrologic Cycle Take a look at St. Joseph or Ste. Mary’s river in Ft. Wayne and relate that to the quotation below “All the rivers run into the sea, yet the sea is not full. To the place from which the rivers come, there they return” Ecle. 1:7 April 2001 Copyright by Dr. Isiorho

April 2001 Copyright by Dr. Isiorho Earth’s Water How much water is there? Approx. 1.36 billion km3 (326 million mile 3) and this amount is fairly constant The continuous circulation of water through the ocean, land and the atmosphere is the process called hydrologic cycle Distribution of Earth’s water ~97 % in ocean; ~2.35% ice/glacier; ~0.65% Lakes, Streams, Groundwater, Atmosphere The largest amount of fresh available to humans- groundwater Glacier and Ice – largest amount of fresh water April 2001 Copyright by Dr. Isiorho

Things you need to know about Streams A stream is a surface water flow confined to a channel Floodplain- flat land immediately surrounding a stream which may be submerged if a river overflows its bank Drainage Basin- land areas that supply surface water to the river Drainage Divide- topographic highland that separates two adjacent drainage basins Tributaries- streams that contribute water to main (trunk) stream Distributaries- main river splits into small channels Graded Stream- state of temporary equilibrium Base level- lowest point to which a river can erode Discharge- the amount of water that flows through a given area (Q=V*A) Types of Rivers- Effluent, Influent, Exotic, Perennials, Intermittent, Ephemeral April 2001 Copyright by Dr. Isiorho

April 2001 Copyright by Dr. Isiorho Stream Erosions Graded Streams- Aggregation- too much sediments Degradation- occurs when there is less sediments Gradient- know how to calculate this Stream Erosion Abrasion Hydraulic lifting Dissolution April 2001 Copyright by Dr. Isiorho

April 2001 Copyright by Dr. Isiorho *Drainage Patterns Streams erode their networks of tributary valleys and distinctive drainage patterns. A drainage pattern is a reflection of the underlying rock material or structure. Drainage Types (Patterns) Dendritic Radial Rectangular Trellis Annular Parallel Deranged Stream Piracy Channel patterns- straight, braided or meandering, oxbow lake April 2001 Copyright by Dr. Isiorho

April 2001 Copyright by Dr. Isiorho Stream Transport Velocity of sediment transport is controlled by its discharge Stream Capacity or carrying Capacity is the total volume of sediments (load) it can carry and it is controlled by its discharge Competence- the maximum size of sediments (load) a stream can carry and it is controlled by its velocity Sediments are transported in the following format Suspended load Bed load Dissolved load April 2001 Copyright by Dr. Isiorho

April 2001 Copyright by Dr. Isiorho Stream Deposition Alluvium- sediment materials that settle from water Point bar- sediments deposited within the channel Flood plain Deposits Levees Backswamp- deposits that make a flood plain’s wetland Alluvial fans- formed where stream valley widens Delta- formed by the deposition of sediments in standing water where the main stream breaks into smaller channels April 2001 Copyright by Dr. Isiorho

April 2001 Copyright by Dr. Isiorho Flood Control Floods occur when water flow exceeds a river’s channel capacity. The 1982 Flood in Ft. Wayne Management Forecast and Prediction Flood Control Structures Levees and Flood walls Alteration of Channels- channelization Flood way zone- structural development restriction April 2001 Copyright by Dr. Isiorho

April 2001 Copyright by Dr. Isiorho Groundwater Types of groundwater– hygroscopic water (not available to plants), capillary water, and gravity water. Porosity is the ratio of the voids to sediment (rock) volume The surface water will percolate downwards until it reaches a zone where all the pore spaces are saturated with water The line that separates the saturated from unsaturated zone is the Water Table A geologic material that is porous, permeable, saturated and will yield enough water when a well is drilled into it is called an AQUIFER April 2001 Copyright by Dr. Isiorho

April 2001 Copyright by Dr. Isiorho Groundwater Movement For groundwater to flow- need porous and permeable materials Porosity is the percent of pore spaces in relation to the total soil/rock/sediment volume Permeability is a measure of the ability of rock/sediment to transmit fluid Groundwater flow occurs when there is a hydraulic gradient Hydraulic conductivity is the ability to transmit groundwater. Typical groundwater flow is slow ~0.5 – 1.5 cm/day (0.2 - 0.6 in/day). The slow movement stores the water making it available to humans. April 2001 Copyright by Dr. Isiorho

Tapping Groundwater Reservoir Groundwater depth is a reflection of local topography and prevailing climate Aquifers are permeable water-bearing bodies of geologic materials Unconfined and Confined aquifers Aquiclude and Aquitard Artesian flow- water flows to the surface from wells without pumping Potentiometric surface Natural Springs Geysers- intermittent surface emission of hot water/steam April 2001 Copyright by Dr. Isiorho

April 2001 Copyright by Dr. Isiorho Groundwater Pumping Features Associated with Pumping Cone of depression- local depression in water around pumping well Subsidence- compressed land due to aquifer depletion Salt water intrusion- due to over pumping along coast line Greater demand for water- leads to groundwater depletion and introduction of pollutant Excessive withdrawal of groundwater from aquifer may result in…land subsidence, change in groundwater flow pattern, cause drawdown, depletion of aquifer Solutions- enhance recharge, water transfer, conservation, desalinization, and use of iceberg April 2001 Copyright by Dr. Isiorho

Groundwater Contaminants/Purification Natural occurring solutes- Chlorine, Arsenic, Mercury, and Selenium Manufacturing contaminants- from household products: cans of paint, solvent, cleanser etc. Natural Groundwater Purification Filtration- adhere to clay particles Decomposition- some decompose completely by oxidation Bacteria action- organic solids consumed by microorganis April 2001 Copyright by Dr. Isiorho

Products of Groundwater Karsts Water reacts with carbon dioxide to form weak carbonic acid which then attacks limestone H2O + CO2 => H2CO3 + CaCO3 => Ca++ HCO3 – Caves- natural underground cavities and most common geological product of limestone dissolution Cave deposits- spelotherms are deposits on cave surfaces in a variety of forms: travertine, Stalactite, Stalagmite, banded draperies or drip curtains Growth of spelotherm- depends on the solution and porosity of surface material, climate, topography, and vegetation April 2001 Copyright by Dr. Isiorho

April 2001 Copyright by Dr. Isiorho Karsts Topography Surface expression of the geology of dissolved limestone and work of near surface water Cave and Karsts landscapes are extremely sensitive- so need to be protected Landform Sinkholes-circular surface depression Disappearing Streams- flow through sinkholes may emerge as spring several kilometers away Natural Bridge- series of neighboring sinkholes expand and join together April 2001 Copyright by Dr. Isiorho