Hydrology is the science of water occurrence, movement and transport.

Hydrology?

Hydrogeology (hydro- meaning water, and -geology meaning the study of rocks) is the part of hydrology that deals with the occurrence, distribution, movement and quality of water beneath the Earth's surface.

Hydrogeology?

Hydrology and Hydrogeology

The world’s freshwater resources are under increasing pressure. Water is vital for human survival, health and dignity and a fundamental resource for human development.

•Resources are scarce•Demands are outstripping supplies

Water cycle

Population underwater stress

Water withdrawals have increased more than twice as fast as population growth and currently more than 1/3rd (2 billions) of world's population live in countries that experience medium to high water stress.

Question: How much percent ofall water is fresh?

Because groundwater has proven difficult to find in many regions, it comprises only 19 percent of the fresh water currently used by the world's population. The key to finding this vast and often untapped resource is the accurate and reliable exploration program.

-GW is significantly less costly to develop than surface water.

-GW is less susceptible to contamination than surface water

- quite often requires little or no treatment to be used as drinking water.

WHERE IS GROUNDWATER?

How much abstraction is feasible? - unplanned abstraction can cause groundwater lowering/mining- Aresnic

To what extent groundwater interactswith surface water?

GW contamination

National Water Policy (1999) --- balanced use of groundwater and surface water

Groundwater Movement

Groundwater Movement

Groundwater Movement

Interaction of Groundwater and Surface Water

Interaction of Groundwater and Surface Water

Baseflow component of surface water flow

Lecture materials/Handouts will be provided at the end of each class.

Reference text:Groundwater Hydrology – By David Keith ToddGroundwater -- By H.M. Raghunath

GradingAttendance: 5%Assignment: 15%Quiz (3 nos): 10%Mid-term : 30%Final : 40%

WFM 5103Hydrogeology and Groundwater

Subsurface environmentWater bearing properties of rocks and soilsPrinciples of groundwater movementRechargeGroundwater withdrawalGroundwater QualityGroundwater in Coastal zonesHydrogeological mappingGroundwater managementConjunctive useGroundwater ModelsGroundwater development in Bangladesh

WFM 5103Hydrogeology and Groundwater

Groundwater withdrawal

WFM 5103Hydrogeology and Groundwater

surface subsurface

- groundwater exploration - hydrogeological mapping

- well construction - well hydraulics

Groundwater Quality- sources of pollution (municipal, agricultural, industrial, etc.)- sources of salinity

WFM 5103Hydrogeology and Groundwater

Hydrogeological mapping

Groundwater management

Conjunctive use

Groundwater in Coastal zones- saltwater intrusion

Aquifer properties/parametersWater transmitting parameter

kggk

K

Permeability orHydraulic Conductivity

epn

vv Mean pore velocity:

K (L/t) --- function of both fluid and porous medium

k (L2) --- function of porous medium only

Water transmittingParameter….contd.