Uni-Directional Flushing Programs

Hydrants, Valves
and water mains

Is your municipality considering a Uni-Directional Flushing (UDF) program?

Is there a capital improvement plan in your near future?

Looking for an asset management program with long-term benefits and cost savings?

Perhaps the time has come for a utility asset condition assessment.

Velocity Water Services has the extensive hydrant and water distribution system knowledge you need to compile the necessary data to achieve these goals.

Contact Velocity Water Services to Schedule Your UDF Program Today

Why Conventional Flushing Doesn't Always Work

Conventional flushing is the opening of individual hydrants, with the intention of discharging water until the water runs clear, and to confirm proper operation of the individual hydrant.

This requires a large amount of water and is less likely to clean the pipe network. With less flow in a given pipe, velocities are often too low to adequately clean and scour the pipes, instead, sediments are just moved throughout the distribution system.


UDF Program Benefits

Uni-directional Hydrant Flushing (UDF) is an excellent, water-efficient method of cleaning water distribution pipes to improve water quality and restore capacity. UDF offers a more effective way of cleaning pipes compared to conventional flushing and uses approximately 40% less water. Equally important, the sediment, corrosion products and biofilm are flushed out and not just moved to another pipe run that's often the case in conventional flushing.

The repairs and replacements made to make your UDF program more effective are usually the same ones that will increase serviceability in your system and reduce the impacts and liability of line breaks in the future. The information alone will allow quicker response time and control of any system failure.

Today utilities operate in environments where pipe failure rates and turbidity problems are commonly exceeding their water main replacement budget. Water mains not flushed on a proactive basis run the risk of building up tuberculation to the point that they cannot be removed by flushing.

Removal of tuberculation is critical, as buildup can have significant impacts on water quality, fire flows, and distribution system efficiency.


UDF Programs Can Also Improve Water Quality and Capacity Through:

  • Reducing iron & manganese concentrations
  • Improving chlorine demand, and turbidity levels
  • Reducing bacterial regrowth
  • Dislodging and removing biofilms
  • Removing sediments and deposits
  • Controlling corrosion
  • Restoring flows and pressures
  • Eliminating taste and odour problems

These benefits can also prolong the life expectancy of the system and reduce the potential for waterborne disease outbreaks.

UDF Programs Offer Many 
Secondary Benefits Including:

  • Prolonging the life of valves 
  • Indicating the location of broken valves and hydrants during the flushing process 
  • Locating closed valves or other obstructions in the water mains 
  • Helping determine the cause of water quality or pressure issues in a specific area of the system 
  • Finding discrepancies between the hydraulic model and the actual distribution system performance  
  • Determining or disproving suspected system issues. 

Contact Velocity Water Services to Schedule Your UDF Program Today