In the case of shafts for drains and sewers with nominal sizes ≥ DN 700, these climbing aids can also be formed onto the pipes sidewise (tangentially) according to DIN V 1201 [ [DINV1201a]] (Image 1‑222) (Image 1‑223) (Image 1‑224).

DIN EN 752 [ [EN752:2008]] defines an inspection chamber as follows: “Chamber with removable cover constructed on a drain or sewer that provides access from surface level only, but does not permit entry of a person”.

Inspection chamber have an internal diameter of less than 800 mm that allow for the insertion of cleaning, inspection and testing equipment [ [EN476:2011]].

Subsequently, only the term inspection chamber will be used in this context.

Inspection …

Catch basin systems serve to take up the precipitation water (subsequently also called runoff or surface water) that is collected at the ground surface (Image 1-12). The precipitation water enters the catch basin via gutters or troughs and is then discharged via one connection sewer/lateral each into the combined sewer systems or surface water sewer for separate systems (Image 1‑232). In addition to the collection and discharge of the precipitation …

Since the beginning of sewer system construction in the 19^th century catch basins were also designated as “street inlets, , gullies” and their constructional design changed over time as a result of changing requirements.

Historically, two differently designs of catch basins were in use:

• Catch basin with an invert outlet,
• Catch basin with a sump.

All other forms that are used in practice today can be traced back to these two designs.

Catch basins with an invert outlet, formerly also called direct catch basins, have been installed for the first time about 1840 in Hamburg, Germany [ [Frühl10]] and thus, they are likely to rank among the oldest storm drain/street outlet constructions in Germany. They were composed of a connection sewer that formed a mouth at the road surface (Image 1‑233). In order to prevent the risk of blockage caused by coarse or bulky material, this opening …

Catch basins with a sump retain the solid matter by means of the sump that acts as a settling container. The maximum water height in the sump is limited by a connection sewer in the main structure. The height of that connection sewer is determined by the water level that should be in a frost-free depth below the upper surface of the road. The depth of the sump varies from city to city. Decisive factors were, for example, a simplification of cleaning …

Already at the beginning of the 20^th century, efforts were being made to standardise catch basins and their built-in parts by means of so-called “DIN models”. However, it was not until 1952 before this approach could be implemented with the introduction of DIN 4052. Up to that point in time, as illustrated in the examples above, there existed numerous non-standardised catch basin designs, as the requirements and guidelines differed from city to city …

For about 30 years now, people have been continually engaged in further developments of catch basins with the objective of improving both the cleaning of these systems [ [Grott1991]] [ [Giesl1997]] [ [[Butle1998]]] and particularly the retention of solids [ [SteinR2004]] [ [SteinR2005]] by means of technical and constructional changes.

In recent years, the objectives were amended by the requirement to also use catch basins as local systems for the …

Drain systems ( (Terminology / Gravity system)) are structural systems used to collect, discharge, dispose of and treat sewage in buildings and on properties. Thus, in comparison to a sewer system, they form part of the private responsibility of the property owners [ [DIN1986-100:2008]].

The limitations of the areas of responsibility are defined in the drainage bylaw of an individual municipality with the following possible allocation options [ [DWARE-…

(Image: Position of private domain sewers under buildings – View into a building pit with laid private domain sewers of vitrified clay (Steinzeug Abwassersysteme GmbH))Private domain sewers are inaccessible pipelines laid in the earth or beneath a foundation that usually carry sewage to a connection sewer or, given a respective legal assignment, directly to the public sewer on the street [ [DIN1986-100:2008]]. They form a wide and complex network …

Without doubt, the biggest problem of our sewer systems are the laterals or drain pipes of drain systems as well as the street run-offs and their connection to public sewers.

Apart from individual exceptions that will be dealt with in detail later on, there was the request that “laterals should, as a rule discharge into the sewers outside of the manholes” [ [ATVA241a]] up until the introduction of DIN EN 1610 [ [EN1610:1997]] in 1997.

(Image: Masonry …

The connections for ventilation and venting serve to discharge the sewer gases and to avoid overpressure and vacuum in the pipe system.

The reasons for the necessity of both ventilation and venting of sewer systems were stated by König in 1902 [ [König02a]] as follows: “Sufficient exchange of air is essential both for health reasons and in consideration of an undisturbed operation of a sewer network; the constant air renewal in the sewers is already …

In the rehabilitation of sewer systems (2nd Volume - in process), neighbouring or crossing pipelines (pipes or cables) may cause considerable difficulties (Animation 1‑4). Therefore, their position relative to the defective sewer, their structural condition and the condition of the surrounding embedment are important criteria for the selection of the respective rehabilitation method in order to prevent subsequent damage.

The type, quantity and distribution …

Fine trees were once a sign of the wealth and vitality of a town. After this perception had sunk into oblivion for a long time and trees became the victim, for instance, of the improvement of street traffic, there has been an increasing tendency for some years in the towns and communities to plan and implement measures for the reintroduction of greenery - even in connection with traffic calming measures.

The importance of tree planting as a town planning …

Since the beginning of modern sewer technology in the 19th century, the essential target of drain and sewer systems is to reduce the health- and safety-related public risks that arise in the context of a collection and transport of wastewater in order to [ [EN752:2008]]:

• Avoid the spread of diseases caused by direct contact to faecal and other pollutions that are contained in the sewage;
• Protect sources of drinking water against a contamination …

The first volume of the 2nd edition of "Rehabilitation and Maintenance of Drains and Sewer" from 2015 gives a comprehensive overview of the state of technology in the area of sewer maintenance and an extensive and detailed description of boundary conditions and structure of drain and sewer systems with an emphasis on pipe materials and joints.

Investigation is the first of the four fundamental activities included in integral sewer management (chapter 1). To a reasonable extent, it is to cover all performance aspects of the drain and sewer system in order to create the basis for the next step (the evaluation of the capacity of the drain and sewer system). The obtained results serve to show compliance to due diligence, and also as the basis for the determination of all activities to be carried …

Apart from damage that has an impact on the structural condition of the system, the age and position of the existing infrastructure, the geotechnical data of the bedding zone and the surrounding subsoil, as well as the potential of damage that could put existing buildings and other supply and drainage facilities at risk should also be included in the considerations for all structural investigations [ [EN752:2008]].

The structural investigations can …

External inspection comprises all measures that are carried out either from the ground surface or specifically prepared explorations. They serve to identify the bedding conditions of the existing sewer or structure, i.e., especially bedding defects and cavities in the pipe run. These have an influence on the reliability, capacity and durability of the soil/pipe system. In many cases, they account for damage of the sewer and also surface settlement …