How to carry out a Red survey

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specification survey sheet example

Draw your field sketches and written descriptive notes, using the three columns: current path condition, work required and descriptiion, on to the site assessment survey sheet, starting at the bottom and working up to the top of the sheet. Use an elastic scale for the pictorial representation and one survey sheet may represent 500m or 50m on the ground. The scale depends on the complexity of the path section, the condition of it, and the amount of actual work that is required. The scale may also vary on individual survey sheets. Both section length and cumulative distance should be measured in metres using a measuring wheel, and recorded in the distance (Dist. (m)) column on the survey sheet.

All the information on the site assessment survey sheet should be entered and read from the bottom of the survey sheet towards the top.

A standard set of picture (hieroglyph) written symbols are used to represent various physical characteristics and recommended path construction works (including any other structures to be installed e.g. bridge) on the ground.

Hieroglyph symbols

The same picture written symbols as used for upland path surveying are suitable for lowland paths, but additional symbols may be required for some path structures or features. Make sure that you include a key on any diagrams that use symbols, including any you have created your self.

Survey Features

bedrock Bedrock
marker boulders Marker boulders
fence Fence
knoll Knoll or bank
photograph Photograph
borrowpit Borrow pit

Drainage Features

Problems Techniques
burn Burn or other watercourse side ditch Side ditch
seepage Seepage or waterflow lett Lett
wet path surface Wet path surface waterbar Waterbar
cross drain Cross drain
stone culvert Stone culvert
piped culvert Piped culvert
ford Ford

Path Features

Problems Techniques
rough path surface Rough path surface aggregate surface Aggregate surface
gully Gully aggregate with geotextile Aggregate with geotextile
aggregate with anchorbars Aggregate with anchor bars
pitching Stone pitching
steps Steps
causeway Causeway

Restoration Features

Problems Techniques
braided paths Braided paths blocking Blocking
hags Turf islands or hags seeding Seeding
turfing Turfing
revetment Revetment

 © Upland Path Advisory Group & Ordie Design Associates

Path sections

To simplify the survey and design work, divide the path into sections using easily identifiable physical features, such as a burn crossing, a building, a bridge, a pond, etc. If you have already commissioned an Amber survey for the route, these sections should match. You may need to divide the sections into shorter subsection lengths in order to provide more detailed and prescriptive information. If no suitable features are present, mark the start and end of sections with discretely located flags, wooden pegs or canes, but remember they will need relocating in the future either by you or someone else. Bear in mind that flags and pegs could get moved or even taken out by people so don’t rely entirely on marking out the sections if there is likely to be a long gap between the survey and construction work. It should be possible for future users of the survey information to locate the start and end points of sections in the field. Mark the route of the path and location of path sections on a 1:25,000 or 1:10,000 map, or use a Geographical Information System (GIS) to take section points which will help with relocation at later time.

How to write up the survey

A ‘neat’ version of the detailed field sketches and written descriptive notes should provide enough information to allow the Designer to 'take-off' the relevant information for preparing drawings, specifications at the detailed design phase. It should identify all elements of path construction work, including any other structural installation work, and possible issues on site. The site assessment survey sheets are likely to form part of tender documentation so it is important that other people can read and understand what you have drawn and written on the sheets. If the information is not clear and concise, do not expect a Designer or Contractor to understand it. Include all written descriptive notes in the right-hand column to explain the detailed field sketches. You will find it useful to include cross-sections of actual path construction work to clearly illustrate dimensions and materials. Similarly, it might be useful to include cross-sections of drainage features (including dimensions) such as piped culverts, cut-off drains, ditches and closed French drains.

Bill of quantities

The bill of quantities is derived from the Red survey and is a useful summary of the work required. It should provide a detailed written description of individual items that have been specified and the number or quantity of each item. Materials that are to be used should be specified and dimensions included. The bill of quantities also forms part of the tender documentation and will be used by tendering Contractors for pricing the proposed path construction works, and any other site preparation or structural installation works.

Time, plant and costs

Provide an estimate of the length of time (number of days of construction work) that the path construction work, including any other associated works, will take to complete – this will help to decide whether the project will need to be notified to the Health and Safety Executive under the Construction (Design and Management) Regulations 2007, not as the case maybe.

Consider what plant and other equipment would be required to undertake the work efficiently. Remember to include the cost of materials and any additional transport costs in your calculations.

The costs can be estimated to provide a budget figure for the work, but bear in mind that Contractor prices can vary greatly according to the location in the country, distance from roads, price of materials and the availability of other work, and timing of the contract.

Useful pointers

  • Remember the users - Make sure that the specifications take account of the needs of the proposed users of the path, and avoid introducing unnecessary physical barriers/ or hazards in the design such as water bars and cross drains

  • Realign if necessary - Evolved path lines that climb directly uphill present various path management problems e.g. fast flowing water causes erosion down the path surface. It may be possible to realign a path to reduce the gradient and make it more attractive to users and less intrusive, allowing the original line to recover

  • Be aware of budgets - If budgets are limited, identify priority sections and ensure that specifications are prepared for those sections first. There is little point wasting resources preparing specifications that are unlikely to happen in the near future. Remember, a Red survey will have a shelf-life of no more than 3 years

  • Use suitably experienced and qualified people - Red surveys rely to a large extent on the judgement and experience of the surveyor. Surveyors should have extensive experience of path design and construction techniques

  • Surveyors are not infallible - Specifications are based on one or two visits to a site. Modifications may be required to design and specifications as work progresses and a contingency plan should allow for this

  • Test the suitability of available materials on site - Do not assume that ‘as dug’ materials will provide the required durable surface or that you will have to import all aggregate for surfacing. A simple test can simulate the effects of compaction, displacement, and erosion in wet and dry conditions on any potential surfacing materials. To find out how to perform a surface materials test, check out the technical tip: 'Testing the Suitability of Surfacing Materials'

  • Use a clinometer to measure the gradient - It can be tempting to look at a route on a slope and try to guess its gradient by sight alone. However, this is a surprisingly difficult skill, so use a clinometer to measure all gradients along the route when surveying. To find out how to use a clinometer to measure gradients, check out the technical tip: 'Don't make the mistake of guessing the gradient'

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