Landscape design irrigation design
Landscape design irrigation design is a discipline involving different applications of design principles for irrigation systems. This discipline incorporates several types of irrigation designs, including mobile, temporary, permanent, automated, and semi-permanent.
In the United States, irrigation engineering and landscape architecture design are often associated and used interchangeably. In Canada, the designations of landscape architecture or landscape engineering have little overlap with the American terms irrigation design and landscape design.
In the United States and Canada, landscape architecture students at architecture schools are often taught irrigation design in their third year, beginning with sprinkler design, and moving to flood irrigation systems in the final year. In Canada, landscaping students at schools of forestry and landscape architecture are generally taught irrigation in the first year. In the United Kingdom, the Associate degree and bachelor degree of landscape architecture have included similar courses to their American counterparts.
The role of irrigation design in landscape design has become more important in recent years due to developments in irrigation technology and an increased awareness of water conservation. There is a need for irrigation design to provide a water-efficient landscape that satisfies the growing demand for water, and that can be readily maintained.
Landscape design begins with a request from a client, a garden designer, or an engineer, for the design of a landscape or garden. The request usually includes a detailed description of what the client wishes to have built, which may include:
A landscape design fee is usually charged for the design of a landscape. This will normally cover the time spent in the initial design phase, such as a site visit, which is typically around three to six weeks. The cost of the design fee can vary greatly depending on the type of work being performed.
During the initial visit, a number of aspects of the proposed landscape are explored. These include the site, and the site's history. Geotechnical studies are often conducted to determine if there is sufficient soil for a new installation, as well as whether the site has an abundance of water or groundwater. The design team will also explore the possibility of having an on-site groundwater source for future irrigation installations, including wells. Is the existing irrigation system intact? Is the current irrigation system sufficient? What is the size and distribution of the trees, shrubs, and other plant life?
Once these aspects have been explored, a more detailed site assessment is conducted. This includes measures of rainfall and evapotranspiration, as well as the location and distribution of perennial and annual water sources, including tanks, septic tanks, and other point sources. The design team may also conduct an inspection of the location of the future irrigation system to see how well-placed it is to be maintained, and if there are any risks of damage or conflict with other plant life.
The initial design, or rough sketch, of a landscape will include basic shapes to represent the various features and elements of the landscape, such as water features, trees, shrubs, lawns, driveways, ponds, and retaining walls. If a tree or other large plant life is present, this will be shown as a 'tree' rather than an arbitrary shape. A design plan is developed to plan the layout and location of each of these elements. A pond may be initially represented as a large lake to reduce its size, but in more detail it may have a dimensioned shape, with a specific area and area shape. Common elements that will be included in the design are:
Away from any perennial water sources, the ground may be covered in grass or turf, which is the preferred form of plant life.
Away from any permanent water sources, the ground may be covered in gravel, for example for a driveway or paths. Occasionally this is a natural gravel deposit, or artificial gravel may be used.
Other plants, such as shrubs and trees, will be assigned a location in the design. Where water features will be located, an inspection of the land may be conducted to see if there are any ponds or lakes or other features that could serve as potential water sources. These will be included in the design as well.
Water from a source (either a water tower or gravity), will flow through an irrigation network which distributes water to the plant life. Most commonly, the irrigation system will be 'gravity fed', where the water source is a nearby perennial water source, such as a lake or dam. As the water reaches the distribution network, it is distributed using lines of sprinklers, usually arranged in a circular pattern for some distribution patterns. Other arrangements of sprinklers are sometimes used, including point-pattern sprinklers and computer-controlled sprinkler systems.
The design of the sprinkler system includes three aspects. They are:
The distribution layout, including the sprinkler distribution lines, drip lines, irrigation head, and valves.
The sizing and flow capacity of the sprinkler heads.
The watering schedule and the frequency of watering.
If a 'floating' or 'pulsed' watering schedule is used, then the watering schedule will specify the time the sprinklers are open. The schedule will provide watering information, such as: the minimum, maximum, and average water flow for the period of time. The frequency may be either continuous or intermittent, depending on the type of system. An 'open period' is the time when the sprinkler is open for a period of time.
These aspects are normally worked out in the design phase, and are then translated into plans and cost estimates. A homeowner will then be provided with a detailed cost estimate for a proposed design. If the design is accepted by the homeowner, it will be incorporated into the construction contract.
A sprinkler system is often not constructed during the design phase. As the system is created, it will be installed on site, and then tested before watering starts. It may also be checked several times during the watering season to make sure it is functioning well. In the US, this