Spring and summer drainage maintenance: roots, smells and dry-weather problems

Warmer months are the cheapest time to fix drainage. Ground conditions are workable, access is easier and you are not competing with storm call-outs. It is also the season when the two most common long-term problems — root ingress and drain odours — become obvious.

Root ingress: spring's signature problem

As trees and hedges come into growth they push fine roots towards the moisture and nutrients leaking from a cracked or open joint. Once inside, roots form a mat that catches paper and solids until the run blocks. Clay pipework, older properties and anything within about ten metres of a mature tree or hedge is at highest risk.

• Repeated blockages in the same section of pipe, particularly after dry spells
• Slow drainage that improves after rodding, then returns within weeks
• Root fragments coming back on a rod or jetting head
• Depressions or lush green patches in a lawn along the line of a drain

Root cutting followed by a CCTV survey is the right sequence — cut the mat out, then look at why they got in. Small defects can often be sealed with a patch liner rather than excavated.

Summer drain smells

Odours peak in hot weather because low flow lets solids sit and dry traps let sewer gas escape. Work through the simple causes first: run water into every unused sink, shower and floor gully to refill the trap; check external gully grates are not caked in debris; and confirm any soil vent pipe or air admittance valve is intact. If smells persist across a property, a defect or a dried-out interceptor trap is more likely and a survey is worthwhile.

Dry weather, ground movement and old clay pipes

Prolonged dry spells shrink clay soils, and that movement opens joints and cracks brittle pipework. Damage often shows up months later as a recurring blockage. If your property is on clay and you had a hot, dry summer, a survey is a sensible precaution before winter loads the system.

Good jobs to book in the warm months

• Pre-purchase or pre-sale CCTV drain survey with a written report
• Root cutting and patch lining on known problem runs
• Septic tank and treatment plant emptying and service
• Soakaway testing and rebuild if it failed during winter
• Planned commercial jetting while sites are quieter over the holidays