6.2 Grassed areas
This section provides the specification for all operations relating to the edging of Turfed and New Areas.
6.2.2 Seed quality
The Contractor shall only use grass seed mixture as approved by the Roads Authority who shall only accept proprietary amenity and sports fine turf grass seed mixtures which contain varieties as approved and featuring in the U.K. seeds list.
Seed mixtures as approved by the Supervisory Officer shall have a germination capacity for each constituent of not less than 85% and a purity of not less than 95%.
6.2.3 Soil quality
The soil is to be approved by the Roads Authority and conforming to British Standard 3882: 1994.
6.2.4 Seeding preparation and seeding
The following procedure shall be undertaken on each occasion:-
All areas shall have all vegetation and extraneous material removed prior to cultivation. Where replacement soil is required due to chemical contamination or fungal/viral disease of turf/soil, it may be necessary to excavate and replace the topsoil to a depth of 300mm, with topsoil as approved by the Roads Authority. The excavated contaminated soil shall be removed from site and disposed of at a licensed tip. A pre-seeding spray of an approved herbicide shall be applied in suitable weather conditions. Allow a suitable fallow period before carrying out cultivation works.
All areas shall be cultivated to a minimum depth of 50mm to produce an acceptable tilth (any stones over 25mm shall be removed).
Where additional topsoil is needed it shall be deposited and spread in layers not exceeding 100mm. Topsoil shall conform to the above Specification Clause and shall be graded to the true specified levels, all depressions shall be eliminated, any undue compaction must be loosened and graded, all to evenly running falls and levels.
Topsoil level shall, after consolidation, be 25mm above adjoining kerbs, manhole covers and similar hard surfaces, and a minimum of 150mm below damp proof course of buildings and walls.
All areas shall be graded at minimum falls of 1 in 60 and a maximum of 1 in 2 to the contours and spot levels.
Unduly compacted areas shall be well ripped to a depth of 100mm and be loosened prior to levelling, raking and seeding.
Where necessary, provision shall be made to take surface water from damp patches and ponding areas by means of land drains, e.g. using 100mm diameter ‘Wavincoil’ type piping, or others as approved by the Roads Authority.
Prior to sowing the surface shall be reduced to a fine tilth as is necessary to a depth of 25mm by raking or harrowing with a chain harrow. All large stones exceeding 25mm diameter shall be removed from the surface, together with all extraneous material.
The Contractor, prior to seeding taking place, shall incorporate and work into the top 50mm of topsoil a pre-seeding fertiliser as approved by the Roads Authority.
Grass seed shall be applied at a rate of 28g per square metre.
When the grass has established and reached a height of 50mm - 70mm it shall be lightly ‘topped’ with a rotary action mower gradually reducing the height, the Roads Authority may then instruct the Contractor to roll the area with a light roller, not exceeding 45kg per 300mm width.
During dry weather conditions the contractor shall make arrangements to ensure that the area is adequately watered to a depth of 75mm.
Any failure whatsoever of seed germination shall be the responsibility of the Contractor, and shall be reinstated, where the Contractor shall bear all costs incurred as a result of this operation
During early establishment periods it may be necessary to protect the seeded area by means of either post and wire sheep net or chespale fencing. At the end of the establishment period the Contractor shall dismantle and remove from site any protective fencing which was required, and fill in the holes with soil to the surface level and re-seed.
Turf edges and margins should be laid with whole turves of a minimum 1m length
Immediately following laying the turf, watering shall be undertaking ensuring that the area has adequate water to penetrate to a depth of 75mm. Further watering may be required, to be undertaken dependent upon weather conditions.
Watering is particularly important when turf is laid, and shall be required to be undertaken on a frequency of twice per week until turf is established, especially if dry weather is experienced.
When turf has established and reached a height of 50mm - 70mm it shall be lightly ‘topped’ with a rotary action mower gradually reducing the height,
Any failure whatsoever, including shrinkage, settlement, dying, scorching, of the turf establishment shall be the responsibility of the Contractor, and shall be reinstated.
During early establishment periods it may be necessary to protect the turfed area by means of either post and sheep net or chespale fencing At the end of the establishment period the Contractor shall dismantle and remove from site any protective fencing which was required, and fill in the holes with soil to the surface level and seed or turf as specified.
Note: These webpages are for reference by developers of housing and employment sites in East Lothian. They provide guidance on transport infrastructure against which Planning Applications will be assessed and evaluated, and set out East Lothian Council's procedures regarding the construction and adoption of new roads in accordance with current legislation. These pages supersede all previous versions of our Standards for Development Roads document. Revisions 01/07/2023 Document release