square lids of sewer hatches

## square lids of sewer hatches: a riddle of the urban environment
Square sewer hatches are not so rare on the streets of many cities in the world, although the round shape seems more familiar and widespread. Their presence gives rise to many questions: why do they exist, what are their advantages and disadvantages compared to round analogues? We will figure it out in more detail.
### Why square? Impractical or functional?
The main reason why they choose a square form is the savings of space and the effective use of materials. Square hatches are more convenient to lay close to each other, forming an even surface, without gaps that can cause failure or hooks. This is especially true when repairing or replacing damaged elements. In some cases, the square form is due to the features of the design of underground utilities, where a specific arrangement of hatches is required. However, such a decision is not without flaws.
### Problems of square hatches
Despite economic benefits, square hatches have some disadvantages. The most important thing is the possibility of failure. Unlike round ones, which, thanks to their form, cannot fall into the mine, a square hatch can turn and fall inside, pose a danger to passers -by. That is why they are more often installed in places with a smaller pedestrian load or with additional safety measures, such as fasteners. In addition, square hatches can be less resistant to heavy vehicles.
### Round against square: an eternal dispute?
As a result, the choice between round and square hatches is a compromise between savings and safety. Round hatches are undoubtedly safer, but also more expensive in production and installation. Square hatches can be more economical, but require more thorough design and installation to avoid risks. Thus, the appearance of square hatches is the result of an attempt to find the optimal solution, given the technical and economic factors. Perhaps in the future there will be new technologies that will help to overcome the shortcomings of a square shape and make it more safe and practical.