The River Environment Classification (REC) is a system that classifies New Zealand's rivers according to their physical properties at a range of spatial scales. The development of REC has been supported by The Ministry for the Environment (MfE) and various regional councils to provide a spatial framework for environmental monitoring and reporting and river management.
Stream order is the numerical position of a tributary or section of a river within the entire network. Headwater streams are assigned a stream order of 1. When two tributaries of the same stream order meet, the order increments by one for the next section downstream. However, if two sections meet where one section has higher order than the other, the next section downstream has the same order as the highest upstream section.
A watershed is a polygon that defines the upstream watershed of a river reach.
The River Environment Classification User Guide contains a comprehensive guide to the REC databases and uses. Updated in May 2010. ISBN 0-478-18919-2 ME Number 499
Time Period of Content
Time Period Information
Maintenance and Update Frequency
West Bounding Coordinate
East Bounding Coordinate
North Bounding Coordinate
South Bounding Coordinate
Licensed under Creative Commons Attribution 3.0 New Zealand.
Point of Contact
Contact Organization Primary
Ministry for the Environment
23 Kate Sheppard Place
Contact Electronic Mail Address
Data Set Credit
Crown Copyright 2004
Native Data Set Environment
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 3; ESRI ArcCatalog 18.104.22.1680