Question: What Is Surface And Subsurface Drainage?

What is centripetal drainage pattern?

In river: Drainage patterns.

Centripetal patterns are produced where drainage converges on a single outlet or sink, as in some craters, eroded structural domes with weak cores, parts of some limestone country, and enclosed desert depressions..

What is the importance of drainage?

Drainage ensures that the soil is properly aerated. If you have excess or standing water it can choke your crops. Drainage reduces soil and nutrient loss from runoff and can help avoid soil erosion.

What is drainage and types of drainage?

Drainage can be either natural or artificial. Many areas have some natural drainage; this means that excess water flows from the farmers’ fields to swamps or to lakes and rivers. … There are two types of artificial drainage: surface drainage and subsurface drainage.

What are the 4 types of drainage patterns?

there are 4 types of drainage patterns on the basis of their flowing pattern-dendritic, trellis, radial and rectangular. dendritic-this pattern resembles branches of trees. ex, the indo-gangetic plains. trellis-in this pattern tributaries join the main rivers at right angles.

What are the advantages of surface drainage?

Advantages of surface drainage are to minimize the duration of ponded water that inundates crops, and to minimize the prolonged saturation of soil which restricts gas (oxygen and carbon dioxide) exchange with the soil and plant root system or which prevents cultural operations.

Does gravel help with drainage?

Gravel (and other rocks) act as barriers that shun rain and other forms of precipitation away from a building’s foundation. Another benefit of using rock for drainage is that exposed rock absorbs the heat from sunlight more than other materials like mulch. Rock then radiates this heat at night.

How do you redirect water runoff?

BUILD A BERM, a small hill covered with grass or other plants that will divert runoff around what you want to protect. … ROUTE THE WATER INTO A DRY WELL. … GRADE BROAD SURFACES to direct runoff away from houses, sheds, barns, and patios. … INTERCEPT THE WATER by using a swale, a shallow ditch with gently sloping sides.More items…•

What kind of gravel should I use for drainage?

The stone should be no less than ¾” and dense (we suggest Granite, or River Gravel) so it will allow good water flow. Lime Rock, although inexpensive, is a poor choice for a French Drain because it will begin to deteriorate over time and eventually begin to pack down and restrict flow.

What is the purpose of subsurface drainage?

Subsurface drainage is concerned with removing water that percolates through or is contained in the underlying subgrade. This water, typically the result of a high water table or exceptionally wet weather, can accumulate under the pavement structure by two chief means: Gravity flow.

How do you control water drainage?

Consider these affordable, do-able solutions to do just that.Add plants. Incorporate plantings, especially in areas where runoff collects. … Protect trees. Like other plant roots, tree roots help absorb and filter runoff. … Break up slabs. … Go permeable. … Catch runoff. … Dig a trench. … Plant a rain garden. … Cover soil.More items…

What are the principles of drainage?

The principles of interception, relief, or pumped-well drainage may be applied to each according to the pattern of subsurface flow. The pattern of flow becomes known from a field investigation of soil stratification, water source, and water table or pressure data.

What is vertical drainage?

The way vertical drainage works is based on the principle that drains are installed vertically into the ground a regular distance apart. These drains have the task of absorbing the inflowing water without significant resistance and draining it away vertically.

What are the types of surface drainage?

Types of Surface Drainage SystemsOpen drains.Humps and Hollows.Levees.Grassed waterways.

What are the three types of drainage patterns?

Drainage patternsDendritic drainage pattern.Parallel drainage pattern.Trellis drainage pattern.Rectangular drainage pattern.Radial drainage pattern.Centripetal drainage pattern.Deranged drainage pattern.Annular drainage pattern.More items…

What is main drainage?

What is off mains drainage? In order for wastewater to be taken away from your property, it will be connected either to a network of pipes leading to a main sewer, or to its own private drainage system, also known as off mains drainage.

What are drainage features?

Natural drainage features include lakes, rivers, swamps, sea, rapids, water falls, cataracts, springs, deltas, fjords, sand or mud, and bays.

Do rocks improve drainage?

Rocks aren’t all bad. Rocks added to the bottom of large pots will reduce the volume of potting soil required to fill a container. So, while they won’t increase drainage they will help to save a few bucks on soil. Of course, the money saved on soil might be much less than the money spent on physiotherapy.

How do you calculate drainage?

The revised roof runoff will be: (1.00 x 1.5 x 500) / 96.23 = 7.79 gallons per minute x 0.35 (runoff coefficient for lawn) = 2.73 gallons per minute. The total runoff equals 2.73 + 4.91 = 7.64 gallons per minute. Now You Try: Calculate the runoff, Q, for each area in each drainage zone.

What is subsurface drainage?

Subsurface drainage systems remove excess groundwater below the ground surface. Perforated plastic drain tubes are placed between 1 and 2 m below the soil surface. The technique was originally called tile drainage because tile cylinders were laid end to end in a trench.

What is poor drainage?

Poorly drained stormwater forms stagnant pools that provide breed- ing sites for disease vectors. Because of this, some diseases are more common in the wet season than the dry season. … Poor drainage can lead to flooding, resulting in property loss, and people may even be forced to move to escape floodwaters.

What is drainage structure?

Drainage of Structures. a system of drains (pipes, boreholes, and subterranean tunnels) intended to collect and draw off groundwater from structures. … Layer drainage consists of drainpipes with filtration cushioning layers. The pipes are laid on water-resistant soil outside the structures to be protected.