The Issue - As part of an application for water abstraction, a company was required to undertake WFD impact assessment.
The assessment needed to cover a wide range of topics such as fisheries, ecology, geomorphology, hydrology and public
amenity; this made it difficult for the company to find one consultancy who could undertake all of the work in a joined-up and
cost effective manner. Additionally, as the project required detailed knowledge of intake design and installation
methodologies, the company also required consultants who would also provide an engineering design service.
The Solution - As Bluengineering undertake a wide range of surveys and assessments in-house we were able to provide an
integrated service which allowed data to be shared between the topics. As we are also engineers we were also able to
design the intake and undertake realistic assessments of the impacts. Where impacts may have occurred, BE’s engineering
knowledge allowed the issues to be designed out, therefore making regulatory approval more likely.
The Issue - During a routine inspection of a commercial felling operation, SEPA identified that poorly installed culverts under
haul roads had led to bed scouring at the discharge points and barriers to fish migration were being formed. Cconsequently
SEPA requested that mitigation measures were developed.
The Solution - Bluengineering undertook an in-field assessment of the culverts and developed a mitigation design using
large stones to build a series of stepped pools, reducing the jump height and allowing levels of water in the culvert to be
increased. Given our experience of such watercourses assumptions could be made regarding the type of species which the
pass needed to cater for and therefore the need for baseline fish surveys was removed and the project timescales shortened
and costs reduced. The design was also made to be flexible and a simple installation method developed which allowed the
forestry contractors to undertake the work on other culverts on site in a cost effective manner.
The Issue - In order to support an application to abstract water for a hydropower scheme, the applicant was requested to
provide a detailed impact assessment for fish habitat within the depleted reach and passage over an existing weir.
The Solution - We undertook a detailed fishery habitat survey, electro fishing surveys and monitored key fish habitat
indicators over a range of flows. This information was used to robustly predict how flow reduction may change habitat
suitability. The data was also used to determine changes in passability over the weir. The study resulted in BE
recommending that the scheme be capped at a size which would lead to minimum changes in habitat and passability.
Although this reduced the scheme’s power rateing, the applicant was not required to install a fish pass and given the
turbine’s lower flow requirement, the scheme could work for a greater proportion of the year. Overall these factors resulted in
the scheme having a higher profitability and lower capital costs then a larger scheme which would have had a greater impact
on fisheries. This result was possible as BE’s services include both environmental and engineering assessments, therefore
an integrated approach could be used which considers all issues together to give clients the best solution.
The Issue - A leisure company was developing a number of cabin holiday centres but given their rural locations, no mains
sewers for foul water disposal where available, therefore soakaways or surface discharge of pre-treated effluent were
required. However, in order for such systems to be put in place the Environment Agency required a H1 risk assessment to
ensure minimal impact to the environment would occur. The waste water treatment specialists also requested information to
allow them to design an appropriately sized drainage field and to determine clean-up targets.
The Solution - For each site BE carried out a screening assessment to identify the most effective disposal route. This took
into account likelihood of the route being acceptable to regulators, technical requirements and cost effectiveness. For
soakaway sites, we then undertook in-field percolation tests and applied the results to H1 risk modelling which allowed the
impact on the environment to be forecasted, the size of the drainage field to be determined and a clean-up target to be set.
For sites where surface water discharges were required BE conducted regulator required baseline monitoring and then
impact modelling leading to a H1 risk assessment and setting of clean- up targets. The information then allowed treatment
systems to be designed and discharge licences to be issued.
The Issue - A water intake needed to be constructed on a river. However, given a high boulder bed load Coanda weirs could
not be used as it would stop the movement of sediment downstream.
The Solution - Bluengineering assessed the site and developed a custom in-bed design which did not require a weir and
would allow both gravels and fish to pass over freely. The development work included BE conducting a wide range of studies
on the river to optimise the design, including flow and gravel movement monitoring. The work, design and results of a flume
test BE undertook were used together with modelling of the structure’s performance to support an impoundment and
abstraction licence application.
Bluengineering have constructed many hydro power schemes, ranging in size from 7kW to 80kW. They have included low
head Archimedes screw turbines, mid-head cross flows and high head Targo systems. A variety of intake systems have also
been used ranging from Coanda weirs, off-channel side intakes and in-bed drop screens. In all cases BE have undertaken
all impact assessments, design and permitting work.
BE are also heavily involved in the installation work, acting as project and site managers, CDM PD & PC, site engineers,
H&S and environmental site management. BE also carried out complex in-channel works directly such as building intakes
and discharges and installing penstocks ranging from 180mm collar fused 100m HDPE roles, 350mm butt fused 6m sticks
to 1,010mm low pressure piping.
The Issue - The Environment Agency identified a water intake for a large paper mill as a high risk to migrating eels. The
agency requested that the screening on the intake was upgraded in a short timescale unless a robust engineering case
could be made for the upgrade work to be phased over a longer period.
The Solution - Following a basic options appraisal, Bluengineering conducted a design appraisal for the favoured screening
operation. This included evaluation of technical effectiveness, project timescales, costs, identification of constraints and
project risks. Robust outline technical designs and project implementation plans were then developed which demonstrated
to the agency the longer timescales were required to implement a cost effective and technically workable upgrade.
The Issue - A farmer wanted to erect a new building, but as the site was near to a river and within a flood risk zone, the
local council’s planning department required a flood risk assessment. The farmer asked various companies for a quote to
undertake the work but all were too expensive compared to the scale of the project and the relatively low risk.
The Solution - Bluengineering provided a flood risk assessment which was tailored to the low risk nature of the
development and the rural setting, as opposed to trying to apply a one size fits all approach. Therefore, a technically robust,
but reasonably priced assessment was produced which allowed the development to proceed.
The Issue - An impact assessment on a impoundment structure to be used for water abstraction was required by the
Environment Agency given that freshwater pearl mussels were located downstream and it was unclear what changes may
occur to the supply of fine gravels which are critical for this endangered species.
The Solution - Bluengineering carried out a detailed survey of the river to gain an understanding of the natural situation. The
data was then used in modelling to predict changes in hydrology and geomorphology which may occur, with our in-house
knowledge of both geomorphology and river structures such as intakes been used.
Our work led to minor design changes to the impoundment weir, after which it was possible to demonstrate that the proposal
would not impact on the downstream mussels.
