Headwater drainage features (HDFs) are the small stream, swale, and wetland features that capture water and transport it to larger streams and rivers.
Some HDFs do not flow all the time, but may flow after rainfall or snowmelt, or due to seasonally high groundwater levels.
HDFs are important! When left in their natural state, these features have many functions — they help to reduce stream flooding, purify water, and provide food and habitat for fish and wildlife.
Urbanization Degrades HDFs
Ecologists are concerned that urbanization can cause degradation of HDFs.
Their small size and the fact that they do not always flow year-round makes HDFs vulnerable to impacts such as piping, channelization, flow diversion, grade lowering, and realignment.
Scientific evidence suggests that HDFs are important sources of food, sediment, nutrients, and flow to downstream aquatic systems. They also provide water quality, storage, and attenuation functions.
To help guide management actions needed to protect HDFs, TRCA and its partners developed a resource: Evaluation, Classification and Management of Headwater Drainage Features Guidelines.
Select the thumbnail below to download the guidelines
What Can You Do to Help?
- Leave HDFs in their natural, undisturbed state.
- Leave vegetation within and around HDFs, maintain existing drainage flow, and keep livestock away.
- Maintain the vegetation surrounding the streams to improve the quality of water and food carried downstream and to remove nutrients and sediment.
HDF Resources
Click to Open Library
LITERATURE REVIEWS
- The Natural Functions of Headwater Drainage Features: A Literature Review, March 2007
- A Review of the Enclosure of Watercourses in Agricultural Landscapes and River Headwater Functions
- The Economic Importance of Agricultural Drainage with Emphasis on the Enclosure of Open Drains in Ontario
- Enclosing Surface Drains: What’s the Story?
HEADWATER MONITORING PROTOCOL
- Constrained Headwater Sampling:
- Unconstrained Headwater Sampling:
RESEARCH
- Richardson, J.S. (2020). Headwater Streams. In M.I. Goldstein & D.A. DellaSala (Eds.), Encyclopedia of the World’s Biomes (pp. 371-378). Elsevier
- Richardson, J.S. (2019). Biological Diversity in Headwater Streams. Water 11: 366
- Kuglerová, L., B.W. Kielstra, R.D. Moore, and J.S. Richardson. (2019). Importance of Scale, Land-Use, and Stream Network Properties for Riparian Plant Communities Along an Urban Gradient. Freshwater Biology 64:587–600
- Chará-Serna, A.M., L.B. Epele, C.A. Morrissey, J.S. Richardson. (2019). Nutrients and Sediment Modify the Impacts of a Neonicotinoid Insecticide on Freshwater Community Structure and Ecosystem Functioning. Science of the Total Environment 692:1291–1303
- Elosegi, A., A. Nicolás, and J.S. Richardson. (2018). Priming of Leaf Litter Decomposition by Algae Seems of Minor Importance in Natural Streams During Autumn. PLoS ONE 13(9): e0200180
- Chará-Serna, A.M., and J.S. Richardson. 2018. Chlorpyrifos Interacts With Other Agricultural Stressors to Alter Stream Communities in Laboratory Microcosms. Ecological Applications 28(1):162–176
- Stanfield, L.W., L. Del Giudice, F. Lutscher, M. Trudeau, L. Alexander, W.F. Fagan, R. Fertik, R. Mackereth, J.S. Richardson, N. Shrestha, G. Tetreault, and M.S.Wipfli. (2014). A Discussion Paper on: Cumulative Effects from Alteration of Headwater Drainage Features and the Loss of Ecosystem Integrity of River Networks. Ontario Ministry of Natural Resources, internal publication, Glenora, Ontario. 21pp
- Hennigar, J. (2012). Effects of Anthropogenic Alterations to Ephemeral and Intermittent Headwater Drainage Features on Downstream Fish Communities. (Master’s Thesis)
- Stanfield, L.W., and D.A. Jackson. (2011). Understanding the Factors that Influence Headwater Stream Flows in Response to Storm Events. Journal of the American Water Resources Association:1-22
- Idika, O. (2010). A Preliminary Investigation into the Ecological Significance of Headwater Drainage Features in Southern Ontario. (Master’s Thesis)
Technical Training
The Ontario Stream Assessment Protocol (OSAP) course is designed to train and certify users in a variety of standardized stream assessment techniques for evaluating habitat, benthos, and fish communities in Ontario’s wadeable streams.
Contact
TRCA Watershed Planning and Ecosystem Science: wpes@trca.ca