Commercial dredging bodies call for science-based regulations

Dredging faces increasingly tight regulations. Credit: Weeks Marine

The dredging world is seeing increasingly restrictive regulations applied to the use of sediment, ship-based emissions, turbidity levels, and dredging windows. In virtually all these cases, the authorities and other decision-makers are setting rules with the intention of protecting the environment.

However, a number of stakeholders from the commercial section of the sector have warned that some of these regulations are not based on scientific evidence or balanced against regular operations.

“I think that some of the regulations have gone too far,” William Doyle, recently appointed CEO and executive
director of the Dredging Contractors of America (DCA) told Fairplay sister publication Dredging and Port Construction on the sidelines of the annual Western Dredging Association conference in Norfolk, Virginia. “There isn’t consistency in regulations between different regions of the US, let alone different countries.”

This is a strong statement given it was voiced by the ex-US Federal Maritime Commissioner. While Doyle is quick to clarify that he isn’t against regulations per se, he is keen on more consistency and a greater degree of realism. “We need our regulators to be making informed decisions,” he insisted.

“One of the issues that drives me nuts is the whole question of turbidity,” he continued, pointing out that turbidity regulations were unevenly applied in the US market and did not conform to scientific observation.

“Look at the Great Lakes. Naturally occurring turbidity after rain storms far exceeds any turbidity from marine construction. Once the storm ends and river run-off stops, the fish aren’t dead and the environment continues to function as normal. We are putting restrictions on dock hammering or dredging, but we aren’t placing any restrictions on nature.”

While he sees the benefits of some limits, he is keen that the authorities consult with scientists and engineers to ensure that they adopt a commonsense approach. “If there is no impact from nature, then an overprotective attitude is unnecessary,” he explained, adding that well-intentioned regulations often hindered the ability of marine engineers to undertake and complete projects. “These projects are vital to the local economy and to the environment, especially in cases where we are undertaking coastal restoration.”

Doyle’s views are shared by the global dredging community, with a number of organisations, including CEDA, organising studies about turbidity levels.

CEDA's approach

The CEDA working group on turbidity limits (WGETL) recently launched its efforts to ensure that imposed turbidity limits were optimised to protect the local environment.

“Environmental turbidity limits for dredging operations should always be site-specific and based on ecosystem functioning in order to protect sensitive environmental receptors,” CEDA told DPC, adding that the dredging industry expended considerable resources on complying with turbidity limits. “By setting realistic limits, monitoring can be made more costeffective and ecologically and socially, relevant.”

The WGETL, which consists of 13 members, is tasked with preparing a CEDA information paper on guidelines for assessing and evaluating environmental turbidity limits for dredging. “The aim of the information paper is to facilitate knowledge exchange on how to assess environmental turbidity limits generally and which parameters should be included in the evaluation at a local level,” the association said.

“The paper also seeks to provide support for legislators and environmental authorities in setting the right thresholds and to encourage contractors and consultants to challenge existing limits that are not site-specific and/or scientifically based.” The paper is scheduled for publication in June next year.

Another topic where Doyle is keen to get regulators on-side is the issue of dredging windows, which he feels are too restrictive. “This is a real concern, as it is hampering our ability to perform operations,” he said, adding that he was keen to see the authorities work with local companies to create more industry best practice.

Doyle intends to use his position with the DCA and his government connections to open conversations to revaluate existing dredging windows with a view to finding the delicate balance between commercial and environmental aims. “I’m hoping they will create wider openings for more dredging – in some instances, there is no need to restrict these windows to four months,” he said.

“Each local company in the DCA has its own regulatory departments and I am working with them to ensure that
local and national governments are educated.”

Beneficial use of sediment

Perhaps the most commercially and environmentally sensitive matter in the spotlight is the beneficial use of marine sediment, where dredged material is used in land reclamation projects. This is an issue that has seen calls from the commercial sector for many years.

“Even after 25 years of limited project implementation we are still finding it difficult to implement anything other than
relatively small-scale projects, often in the form of small ‘trials’,” Colin Scott, head of business development at ABPmer’s habitat creation arm wrote in his summary of the company’s 2016 conference on the topic.

“We have proven these work and we have the knowledge and technical capability to be doing more and better,” he continued, pointing out that treating dredged material as waste was shortsighted. “We are missing opportunities, due to the obstacles that exist.”

Noting that complex regulations, lack of clarity, and ongoing inconsistency constrained implementation, he echoed Doyle’s call for a sensible approach by regulators. “There is also a tendency to place emphasis on not doing things unless all evidence to the contrary is in place and all risk is removed, rather than having a proactive, ‘can do’ or ‘yes if’ approach, in which there is a presumption in favour of habitat restoration,” he said.

It is noteworthy that the International Maritime Organization (IMO) is keen to provide more clarity about this issue and for sediment be used beneficially, as this aligns with the framework set out by the London Protocol, which restricts the dumping of waste at sea.

“[The protocol] effectively banned waste disposal at sea. Only eight wastes can be disposed at sea, and only if they
have been thoroughly assessed,” Andrew Birchenough, technical officer at the IMO’s marine environment division in the office for the London Convention/Protocol and ocean affairs told DPC.