Rules, standards and guidelines

Current regulations: The applicable technical rules and standards must be observed when planning, constructing, and operating drainage channels. In the past, DIN 19580 (Drainage channels for rainwater for installation in traffic areas) and the "Guidelines for the Design of Roads, Part: Drainage (RAS-Ew)" were particularly relevant. These have since been superseded by newer European standards and guidelines: The standard DIN EN 1433 (first edition 2002, introduced in Germany in 2005) regulates the classification, construction and testing principles, marking, and conformity of drainage channels throughout Europe. In road construction, the RAS-Ew was last updated in 2005 and replaced in 2021 by the REwS (Guideline for the Drainage of Roads, 2021 edition). New rules have also been established in the water management sector. Standards and guidelines – old and new: The following table provides an overview of important older regulations in the context of surface drainage and their current status:

Formerly: DIN 19580:1988 “Drainage channels for traffic areas” Today: DIN EN 1433 (EN 1433:2002, published in DE 2005) as the central product standard with load classes A 15–F 900; in Germany supplemented by DIN 19580:2010 (national requirements including durability and conformity).

Formerly: RAS-Ew (Guidelines for the Design of Roads – Part: Drainage), Edition 1987/2005. Today: REwS (Guideline for the Drainage of Roads), Edition 2021 – replaces RAS-Ew; applies to rural roads (new construction as well as reconstruction/expansion) and analogously to ancillary facilities (e.g. parking lots).

Previously: DWA M 153 (2007) as the central “recommendation for action” Today: DWA A/M 102 series (2020–2023); e.g. DWA A 102-2/BWK A 32 (12/2020) for emission-related assessments/regulations for discharges into surface waters.

Formerly: ATV DVWK A 138 (2005), later updates. Today: DWA A 138-1 (White print 10/2024) – new, comprehensive revision for the planning, design, construction and operation of infiltration systems in residential areas.

Previously: national standards such as DIN 1229, DIN 4052 (etc.) Today: DIN EN 124-1:2015 to DIN EN 124-5:20215 – definitions, classification, general design principles, performance requirements and test methods Important: EN 124 does not apply to grates/covers that are part of a prefabricated drainage channel according to EN 1433 – these fall under EN 1433.

Principle (§ 55 WHG): Rainwater should be infiltrated, allowed to seep into the ground, or (separately) discharged locally, provided there are no legal or water management reasons to the contrary. Exemption from permitting requirements (§ 46 para. 2 WHG): Federal states may, by statutory order, provide for the permit-free, harmless infiltration of rainwater. (Details are regulated by state law.)

Section 9 Paragraph 1 No. 14 of the German Federal Building Code (BauGB): Municipalities may designate areas for wastewater disposal, including retention and infiltration of rainwater (planning certainty for swales, trenches, retention basins).