The pipeline is owned by Dakota Access, LLC, controlled by Energy Transfer Partners, with minority interests from Phillips 66, and affiliates of Enbridge and Marathon Petroleum.

[11] Meetings in Fort Madison, Sioux Center, Oskaloosa and Storm Lake brought out hundreds of people expressing their support and/or opposition to the pipeline.

[21] In April 2015, Iowa Senate Study Bill 1276 and House Study Bill 249 advanced with both Senator Robert Hogg, D-Cedar Rapids, and State Representative Bobby Kaufmann, R-Wilton, in support; it required Dakota Access "to obtain voluntary easements from 75% of property owners along the route before eminent domain could be authorized".

[23] Conditions of the approval included liability insurance of at least $25 million; guarantees that the parent companies of Dakota Access will pay for damages created by a pipeline leak or spill; a revised agricultural impact mitigation plan; a timeline for construction notices; modified condemnation easement forms; and a statement accepting the terms and condition's of the board's order.

[26] A week later, Dakota Access filed motions with the IUB requesting expedited and confidential treatment to begin construction immediately, saying it met the conditions and that its liability insurance policies were trade secrets under Iowa law and "would serve no public purpose".

[31] In June 2016, the IUB voted 2 to 1 (Libby Jacobs and Nick Wagner in favor and Chairwoman Geri Huser against) to allow construction on non-sovereign lands to continue.

[32] In late June 2016, construction was allowed to resume in Lyon County after plans were changed to route the pipeline 85 feet (26 m) below the site using directional boring, instead of trenching and disturbing the soil on the surface.

[34] In July and August 2016, The United States Army Corps of Engineers (USACE) approved the water crossing permits and issued all but one permission necessary for the pipeline construction.

[44] On September 9, 2016, the US Departments of Justice, Army, and Interior issued a joint statement to temporarily halt the project on federal land bordering or under the Lake Oahe reservoir.

The US federal government asked the company for a "voluntary pause" on construction near the area until further study was done in the region extending 20 miles (32 km) around Lake Oahe.

[46] On September 13, 2016, chairman and CEO of Energy Transfer Partners Kelcy Warren said concerns about the pipeline's impact on the water supply were "unfounded", that "multiple archaeological studies conducted with state historic preservation offices found no sacred items along the route" and that the company would meet with officials in Washington "to understand their position and reiterate our commitment to bring the Dakota Access Pipeline into operation.

"[47] On November 1, 2016, President Obama announced his administration was monitoring the situation and had been in contact with the USACE to examine the possibility of rerouting the pipeline to avoid sacred lands.

"[49] Energy Transfer Partners responded by criticizing the Obama administration for "political interference" and said that "further delay in the consideration of this case would add millions of dollars more each month in costs which cannot be recovered."

[50] Craig Stevens, spokesman for the Midwest Alliance for Infrastructure Now (MAIN) Coalition, called the Corps's announcement "yet another attempt at death by delay" and said the Obama administration "has chosen to further fan the flames of protest by more inaction."

North Dakota Senator John Hoeven said in a statement that the delay "will only prolong the disruption in the region caused by protests and make life difficult for everyone who lives and works in the area.

[52] On December 4, 2016, the USACE announced, it would not grant an easement for the pipeline to be drilled under Lake Oahe and was undertaking an environmental impact statement to look at possible alternative routes.

The proposed EIS was to consider "Alternative locations for the pipeline crossing the Missouri River", direct and indirect risks and impacts, as well as their treaty rights to the lake.

[85] The developer argued that the pipeline improves the overall safety to the public, would help the US to attain energy independence, and is a more reliable and safer method of transport to refineries than rail or road.

[104] The Bismarck route was rejected by the United States Army Corps of Engineers (USACE) before submitting a request to the North Dakota Public Service Commission (NDPSC) for a permit.

[112] The USACE has conducted a limited review of the route, involving an environmental assessment of river crossings and portions of the project related to specific permits, and issued a finding of no significant impact.

[124] In March 2015, a Des Moines Register poll found that while 57% of Iowans supported the Dakota Access Pipeline, 74% were opposed to the use of eminent domain condemnation on behalf of a private corporation.

[131] Saying that "the Corps effectively wrote off the tribe's concerns and ignored the pipeline's impacts to sacred sites and culturally important landscapes", the Standing Rock Sioux Tribe has sued the USACE in the United States District Court for the District of Columbia, accusing the agency of violating the National Historic Preservation Act and other laws, and seeking declaratory and injunctive relief to stop the pipeline.

"[133] On September 20, 2016, Dave Archambault II addressed the UN Human Rights Council in Geneva, Switzerland, where he called "upon all parties to stop the construction of the Dakota Access Pipeline."

"[134] On September 22, 2016, Victoria Tauli-Corpuz, a United Nations expert on the rights of indigenous peoples, admonished the U.S., saying, "The tribe was denied access to information and excluded from consultations at the planning stage of the project, and environmental assessments failed to disclose the presence and proximity of the Standing Rock Sioux Reservation."

[142] On September 2, 2016, Tim Mentz, a former historic preservation officer for the Standing Rock Sioux, testified in DC District Court that 27 graves and 82 sacred sites were to be disturbed by the Cannonball river section of the pipeline.

[142][145][146][147] On September 21, 2016, 1,281 anthropologists, archaeologists, museum officials, and others signed and released a letter in support of the tribal community, calling for further study of the area to be affected by the pipeline in South Dakota.

[142][144] Jon Eagle, a Historic Preservation Officer for the tribe, was invited to participate in the evaluation on Sept. 23, but was not allowed access to the areas of the corridor on private property.

[142][145][146][147] According to his federal disclosure forms, filed in May 2016, President Donald Trump held between $15,000 and $50,000 in stock in Energy Transfer Partners – down from $500,000 to $1 million in 2015 – and between $100,000 and $250,000 in Phillips 66.

[83][132] While the protests drew international attention and were said to be "reshaping the national conversation for any environmental project that would cross the Native American land",[158] there was limited mainstream media coverage of the events in the United States until early September 2016.

[160][161][162][163] In late October, armed soldiers and police with riot gear and military equipment cleared an encampment that was directly in the proposed pipeline's path.