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Drainage systems

Published: | Category: Drainage , Maintenance , Specifications | Audiences: Road traffic engineers & consultants, Roading contractors

This specification replaces specification TNZ C16 Specification for maintenance of stormwater structures. However, if TNZ C16 is referred to in existing contract documents then you may continue to use it.

Publication details

  • Author:
  • Published: 2006
  • Reference: TNZ HM/21
  • Conditions: Use is mandatory on state highways and recommended on other road controlling authority roads.
  • Also known as: HM21

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  1. Drainage Systems — 4 pages, 124 KB
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