A water tender, also known as a tanker, is designed for transporting water to a fire scene. Essentially a large tank on wheels, tenders are able to collect water from various sourcess including: ponds, rivers, lakes, and hydrants. The water is then transported to terrain where no hydrant system or other water source is present. Unlike a fire engine, tenders do not have the pumping capacity to power large hose lines, but a smaller on-board pump allows for water to be taken from water sources and supply fire engine(s) with a very rapid connection to begin extinguishment.   In the US, water tenders are are required to carry 1000 gallons per NFPA standards (National Fire Protection Association). Some may carry up to 5000 gallons, and if a trailer is attached, even more water can be carried. As a result of the amount of weight carried by a water tender, the driver must account for a top-heavy sensation and take caution when operating the rig to avoid tipping or overturning. Once deployed, tenders are multi-functional and support relief in emergencies such as fires, chemical spills, clean-up of auto accidents, and pumping in flooded areas.   Because water tenders provide water and pumping capabilities to areas where there may be no source, they are versatile pieces of equipment that can be essential to emergency relief in remote areas where independent operation may be crucial. Deployment in diverse settings such as forrest, building, and industrial fires also require that most tenders carry some basic fire fighting equipment. A variety of hoses, spray nozzles, axes, flashlights, portable fire extinguishers, breathing apparatuses, first aid supplies, and fire hydrant connections can all be required aboard a tender depending on departmental or regional standards. Though typically utilized as a support piece, water tenders are capable of carrying responders and equipment in addition to valuable water supplies, thus allowing them to serve as primary apparatuses when the circumstances of the emergency require that role.