1. Firstly, consider the Health and Safety Aspects. Most floodwater is contaminated to some degree. If floodwater has been contaminated then there are health concerns in handling affected soil and turf. Take advice from the relevant agencies and get the deposits tested for any potential Health and Safety risks. You need to know what you are dealing with to be able protect yourself and your staff properly. You will also need to ensure that anyone who may come into contact with the site is aware of any potential risks (e.g. signage).
2. The turf. Firstly don't despair. As long as the turf isn't submerged under stagnant water for a prolonged period then it should recover.
3. If there has been significant flooding then some assessment of the effect on growing conditions is required. The following strategy should be adopted:-
(a)Take a representative sample of the deposit and upper soil profile(keep separate if possible). Take soil cores to a minimum depth of 25mm obtaining 0.5kg soil. Ensure appropriate protective clothing is worn and the samples are sealed correctly.
(b)The following soil analyses should be carried out:-
Growth test : Provides a general indication if anything toxic present.
Salinity test : Any soluble salts present will affect plant growth, but can be quickly washed out with fresh water.
If there is likely to have been any industrial contamination:-
Heavy metal test : High concentration of elements such as copper and nickel could have long term effects on growth.
A visual examination should be made to assess the accumulation and implications of any surface silt.
(c)If the tests are clear then overseeding can be carried out.
(d)If contamination is present then it may be necessary to take remedial action on the growing medium. This may include scraping of thick deposits, power jetting of thinner deposits and scarification or brushing of dry deposits. Take all necessary safety precautions and be sure to dispose of contaminated waste appropriately.