Hydrologists study water and the water cycle. They study the movement, distribution, and other properties of water, and they analyze how these influence the surrounding environment. They use their expertise to solve problems concerning water quality and availability, for example.
Hydrologists typically do the following:
Hydrologists use remote sensing equipment to collect data. They or technicians whom they supervise usually install and maintain this equipment.
They also use sophisticated computer programs to analyze and model data. They use sophisticated laboratory equipment to analyze chemical samples collected in the field.
Hydrologists work closely with engineers, scientists, and public officials to study and manage the water supply. For example, they work with policy makers to develop water conservation plans and with biologists to monitor marine wildlife.
Most hydrologists specialize in a specific water source or a certain aspect of the water cycle, such as the evaporation of water from lakes and streams. Some of the most common specialties are:
Groundwater hydrologists study the water below the Earth's surface. They decide the best locations for wells and the amount of water that should be pumped. They are often consulted about the best places to build waste disposal sites to ensure that the waste does not contaminate the groundwater.
Hydrometeorologists study the relationship between surface waters and water in the atmosphere. For example, to predict and prepare for droughts, they study how much rain or snow a particular area gets and how that evaporates.
Surface water hydrologists study water from above ground sources such as streams, lakes, and snow packs. They may predict future water levels and usage to help reservoir managers decide when to release or store water. They also produce flood forecasts and help develop flood management plans.
Some people with a hydrology background become professors or teachers. For more information, see the profile on postsecondary teachers.
Civil engineers design and supervise large construction projects, including roads, buildings, airports, tunnels, dams, bridges, and systems for water supply and sewage treatment.
Civil engineers typically do the following:
Many civil engineers hold supervisory or administrative positions ranging from supervisor of a construction site to city engineer. Others work in design, construction, research, and teaching. They work with others on projects and may be assisted by civil engineering technicians and technologists.
The federal government employs about 12,100 civil engineers to do many of the same things done in private industry, except that the federally employed civil engineers may also inspect projects to be sure that they comply with regulations.
Civil engineers work on complex projects, so they usually specialize in one of several areas.
Geotechnical engineers work to make sure that foundations are solid. They focus on how structures built by civil engineers, such as buildings and tunnels, interact with the earth (including soil and rock). Additionally, they design and plan for slopes, retaining walls, and tunnels.
Structural engineers design and assess major projects, such as bridges or dams, to ensure their strength and durability.
Transportation engineers plan and design everyday systems, such as streets and highways, but they also plan larger projects, such as airports, ports, and harbors.
Janitors and building cleaners keep many types of buildings clean, orderly, and in good condition.
Janitors and building cleaners typically do the following:
Janitors and building cleaning workers keep office buildings, schools, hospitals, retail stores, hotels, and other places clean, sanitary, and in good condition. Some do only cleaning, while others have a wide range of duties.
In addition to keeping the inside of buildings clean and orderly, some janitors and building cleaners work outdoors, mowing lawns, sweeping walkways, or shoveling snow. Some janitors also monitor the heating and cooling system, ensuring that it functions properly.
Janitors and building cleaners use many tools and equipment. Simple cleaning tools may include mops, brooms, rakes, and shovels. Other tools may include snowblowers and floor buffers.
Some janitors may be responsible for repairing small problems with electricity or plumbing, such as leaky faucets.
Brickmasons, blockmasons, and stonemasons (or, simply, masons) use bricks, concrete blocks, and natural stones to build fences, walkways, walls, and other structures.
Masons typically do the following:
The following are common types of masons:
Brickmasons and blockmasons--who often are called bricklayers--build and repair walls, floors, partitions, fireplaces, chimneys, and other structures with brick, precast masonry panels, concrete block, and other masonry materials.
Pointing, cleaning, and caulking workers repair brickwork, particularly on older structures on which mortar has come loose. Special care must be taken not to damage the structural integrity or the existing bricks.
Refractory masons are brickmasons who specialize in installing firebrick and refractory tile in high-temperature boilers, furnaces, cupolas, ladles, and soaking pits in industrial establishments. Most of these workers are employed in steel mills, where molten materials flow on refractory beds from furnaces to rolling machines. They also are employed at oil refineries, glass furnaces, incinerators, and other locations with manufacturing processes that require high temperatures.
Stonemasons build stone walls, as well as set stone exteriors and floors. They work with two types of stone: natural-cut stone, such as marble, granite, and limestone; and artificial stone, made from concrete, marble chips, or other masonry materials. Using a special hammer or a diamond-blade saw, workers cut stone to make various shapes and sizes. Some stonemasons specialize in setting marble, which is similar to setting large pieces of stone.
Cement masons pour, smooth, and finish concrete floors, sidewalks, roads, and curbs. Using a cement mixture, terrazzo workers create durable and decorative surfaces for floors and stairways.
Cement masons typically do the following:
Terrazzo workers typically do the following (in addition to what cement masons do):
Concrete is one of the most common and durable materials used in construction. Once set, concrete--a mixture of cement, sand, gravel, and water--becomes the foundation for everything from decorative patios and floors to huge dams or miles of roadways.
The following are types of cement masons and terrazzo workers:
Cement masons and concrete finishers place and finish concrete. They may color concrete surfaces, expose aggregate (small stones) in walls and sidewalks, or make concrete beams, columns, and panels.
Throughout the process of pouring, leveling, and finishing concrete, cement masons must monitor how the wind, heat, or cold affects the curing of the concrete. They must have a thorough knowledge of the characteristics of concrete so that, by using sight and touch, they can determine what is happening to the concrete and take measures to prevent defects.
Terrazzo workers and finishers create decorative walkways, floors, patios, and panels. Although much of the preliminary work in pouring, leveling, and finishing concrete is similar to that of cement masons, terrazzo workers create more decorative finishes by blending a fine marble chip into the cement, which is often colored. Once the terrazzo is thoroughly set, workers correct any depressions or imperfections with a grinder to create a smooth, uniform finish.