science, which deals with the occurrence, distribution and disposal of water on the planet earth; it is the science which deals with the various phases of the hydrologic cycle.
Hydrology
branch of engineering that applies fluid mechanics principles to problems dealing with the collection, storage, control, transport, regulation, measurement, and use of water.
Hydraulics
Scope of Hydrology
- Maximum probable flood that may occur
- Water yield from a basin
- Ground water development
- Maximum intensity of storm and its frequency
10 Hydrologic Data
- Climatological
- Cropping pattern
- Stream-flow records
- Seasonal fluctuation of ground water table
- Hydrometeorological
- Hydrometeorological characteristics of basin
- Precipitation records
- Evaporation data
- Water quality data
- Geomorphologic studies of the basin
is the water transfer cycle, which occurs continuously in nature.
Hydrologic Cycle
7 Important Phases of Hydrologic Cycle
- Evaporation
- Evapo-transpiration or Transpiration
- Condensation
- Runoff
- Infiltration
- Precipitation
- Groundwater Flow
For every stream, a well-defined area of land intercepts the
rainfall and transports it to the stream. The area of land is called the
Catchment area, Watershed, or Drainage Basin
bent contour lines that point uphill
Swale
bent contour lines that point downhill
Ridge
transition between two ridges and two swales
Saddle
4 Steps of Watershed Delienation
- Identify peak points
- Connect each peak
- Locate the draining point.
- Find the watershed area using squares
5 Rules of Watershed Delienation
- Draw the divide perpendicular to contour lines
- Draw the divide along a ridge and across a saddle.
- Never draw the divide along or across a swale.
- Draw the divide between and parallel to two contour lines of the same elevation.
- Imagine a drop of rain, then trace the runoff path taken by the drop.
11 Watershed Reservations in the Philippines
- Magat
- Makiling-Banahaw
- Pulangi
- Pantabangan
- Buhi-Barit
- Upper Agno
- San Roque
- Angat
- Lake Lanao
- Caliraya
- Tiwi
releases 10 times more water than it receives from its own catchment area
La Mesa Reservoir
It connects the whole basic to Manila Bay through Pasig River.
Manila Subbasin
resulting from the mix of fresh and saltwater
Brackish Water
is the only stream through which Laguna de Bay drains to Manila Bay
Pasig River
is the 2nd largest major subbasin within the Manila Bay Watershed Area
Pasig-Marikina-Laguna de Bay Basin
To mitigate flooding downstream, which includes a portion of the highly urbanized Metro Manila, flood water are diverted to Laguna de Bay through the
Rosario Weir and Manggahan Floodway
has the longest coastline along Manila Bay.
Cavite River Basin
