Litter in the context of "High water mark"

A high water mark is a point that represents the maximum rise of a body of water over land. Such a mark is often the result of a flood, but high water marks may reflect an all-time high, an annual high (highest level to which water rose that year) or the high point for some other division of time. Knowledge of the high water mark for an area is useful in managing the development of that area, particularly in making preparations for flood surges. High water marks from floods have been measured for planning purposes since at least as far back as the civilizations of ancient Egypt. It is a common practice to create a physical marker indicating one or more of the highest water marks for an area, usually with a line at the level to which the water rose, and a notation of the date on which this high water mark was set. This may be a free-standing flood level sign or other marker, or it may be affixed to a building or other structure that was standing at the time of the flood that set the mark.

A high water mark is not necessarily an actual physical mark, but it is possible for water rising to a high point to leave a lasting physical impression such as floodwater staining. A landscape marking left by the high water mark of ordinary tidal action may be called a strandline and is typically composed of debris left by high tide. The area at the top of a beach where debris is deposited is an example of this phenomenon. Where there are tides, this line is formed by the highest position of the tide, and moves up and down the beach on a fortnightly cycle. The debris is chiefly composed of rotting seaweed, but can also include a large amount of litter, either from ships at sea or from sewage outflows.

A street sweeper or street cleaner is a person or machine that cleans streets.

People have worked in cities as "sanitation workers" since sanitation and waste removal became a priority. A street-sweeping person would use a broom and shovel to clean off litter, animal waste and filth that accumulated on streets. Later, water hoses were used to wash the streets.

Debris (UK: /ˈdɛbri, ˈdeɪbri/, US: /dəˈbriː/) is rubble, wreckage, ruins, litter and discarded garbage/refuse/trash, scattered remains of something destroyed, or, as in geology, large rock fragments left by a melting glacier, etc. Depending on context, debris can refer to a number of different things. The first apparent use of the French word in English is in a 1701 description of the army of Prince Rupert upon its retreat from a battle with the army of Oliver Cromwell, in England.

A cleanup or clean-up is a form of environmental volunteering where a group of people get together to pick-up and dispose of litter in a designated location. Cleanups can take place on a street, in a neighborhood, at a park, on a water stream, or other public spaces. Cleanup events are often volunteer run. The cleanup volunteers make sure the waste picked-up is disposed of in its appropriate place. Cleanup events are often community-centered and led.

During the COVID-19 pandemic litter picking participation has greatly increased in the UK. There are a vast range of reasons that people take part in litter picking activities. These include: clearing up unsightly areas; protecting wildlife; keeping people safe, connecting with nature, finding valuables, being part of a community, mental and physical health benefits and acting to protect the environment.

Road debris, a form of road hazard, is debris that accumulates on or off a road. Road debris includes substances, materials, and objects that are foreign to the normal roadway environment. Debris may be produced by vehicular or non-vehicular sources, although in all cases it is considered litter, a form of solid waste. Debris may tend to collect in areas where vehicles do not drive, such as on the edges (shoulder), around traffic islands, and junctions.

Road spray or tire kickup is road debris (usually liquid water) that has been kicked up, pushed out, or sprayed out from, a tire. In 2004, a AAA Foundation for Traffic Safety study revealed that vehicle-related road debris caused 25,000 accidents and nearly 100 deaths a year.