The House of Commons inched one step closer to a possible procedural showdown with the Senate Thursday after MPs rejected several amendments to the Trudeau government’s proposed overhaul of this country’s transportation system.

In March, the Senate transportation and communication committee made nineteen amendments to bill C-49, a broad piece of legislation that would modernize the Canada Transportation Act. The bill has been on Parliament’s agenda since last year.

Transport Minister Marc Garneau announced late last week he was opposed to nine of the Senate’s changes and amended several more.

Garneau told the Commons Thursday that the government has “taken the time to carefully review each proposed amendment” and said C-49 is a “transformational” piece of legislation.

Early Thursday afternoon, the Liberals used their majority and voted in favour of Garneau’s decision – a move that sends the file back to the Red Chamber for reconsideration. Agriculture Minister Lawrence MacAulay has said he supports the changes and decisions made by his cabinet colleague, Garneau.

NDP MPs and Conservative MPs voted against the Liberals response to the Senate’s amendments. A Conservative motion calling for the Liberals to accept all of the Senate amendments was defeated – despite earning support from the NDP.

However, the Liberals’ decision to push ahead with the transport minister’s changes come despite ongoing disagreement from several stakeholder groups, including the Mining Association of Canada.

Brendan Marshall, the association’s vice-president of economic and northern affairs, told iPolitics Wednesday his organization is “completely in disagreement” with Garneau and Transport Canada over his decision to reject an amendment on final offer arbitration (FOA). Many shippers have long demanded the inclusion of costing information to ensure the rates demanded by CN and CP are fair.

The federal transport minister has rejected that amendment – arguing it is is not a rate based measure – despite the fact the concept is backed by groups including the Western Canadian Shippers Coalition, Pulse Canada, Fertilizer Canada, Forest Products Association of Canada, the Mining Association of Canada, the Chemistry Industry Association of Canada, the Freight Management Association of Canada and the Canadian Fuels Association.

“I don’t know how anyone could understand or think that service provision has nothing to do with cost,” Brendan Marshall, the association’s vice-president of economic and northern affairs, told iPolitics Wednesday.

“There are costs associated with doing anything, and when you’re trying to assess what a reasonable rate of return is for a given level of service, the costs associated with procuring that service are fundamental to assessing what a reasonable rate of return is,” Marshall said.

“We are completely in disagreement with his department on that point and in all of our engagements with him and with his department we received zero rationale as to why they believe what they believe.”

Canada’s mining industry is also concerned about the federal government’s decision to create a new long-haul interswitching system, Marshall explained, noting the association has been advised by experts the proposed policy will not work as Ottawa expects it will.

The Mining Association is also upset with the transport minister’s requested change to an amendment around ‘own motion power’ that would require the Canadian Transportation Agency to seek ministerial permission to investigate suspicions of poor service. That change, Marshall said, erodes the agency’s arms length status.

Conservative Critic for Transport, Kelly Block, has called the change “disingenuous” while Conservative Agriculture Critic John Barlow has argued the Liberals’ amendment results in a “watered-down” version of ‘own motion power.’

Western Canadian shippers have long demanded the CTA be granted ‘own motion powers’ so that service issues can be investigated without a formal complaint.

Under the Senate’s proposed amendment, which Garneau has rejected, the agency would not be required to seek permission from the minister to conduct an investigation and is not required to abide by terms and conditions set out by him or her.

The majority of Western Canadian farm groups have said they’re comfortable with the minister’s wording around the ‘own motion power’ portion of the legislation, arguing while the legislation isn’t perfect it must be passed before Parliament rises in June so that it is in place before the start of the next crop year.

Millions of tonnes of Prairie grain and other commodities have been stuck across Western Canada for months because of poor rail service. It is the second backlog to hit the region in five years. The 2013-2014 backlog is estimated to have cost the region up to $8 billion in economic losses.

In March, Garneau and MacAulay wrote Canadian Pacific and Canadian National, urging them to improve their service in Western Canada. On Thursday, the federal transport minister told the Commons there is “no question the railways must do better.”

CN Railway said on Twitter this week it had filled all of the grain car orders for the week and “is current to demand and is seeking additional export orders from grain companies.”

CN has met all grain orders in Western Canada for the third straight week, is current to demand and is seeking additional export orders from grain companies. View the latest weekly grain report: https://t.co/UDZFRdKduf #WestCdnAg pic.twitter.com/iZXYSCN93V — Canadian National (@CNRailway) May 2, 2018

Upon receipt, the Senate could decide to reject the House of Commons decision and choose to add certain amendments back in. Senators could also opt to alter the wording of some of the Liberals’ amendments.

The bill cannot become law until both Houses of Parliament agree to the same legislative language.

A date for the Senate debate of the bill has not yet been set. Parliament is set to rise for its summer recess in June.