Question: In what year did the rival school, located in Summerlin, to Durango High School open?

Context articles: Chesapeake High School (Anne Arundel County)
South River High School (Maryland)
Lapeer East High School
Bishop Gorman High School
Durango High School (Nevada)
Holy Cross High School (River Grove, Illinois)
Norco High School
Durango High School
Robert Logan Patton High School
Spring Valley High School (Nevada)

Chesapeake Senior High School (CHS) is one of two high schools in Maryland by that name.
 The other is the Chesapeake High School of Baltimore County, Although, the school in Baltimore County is strictly Chesapeake High and does not include Senior in its name as does Chesapeake Senior High in Anne Arundel County.
 It is one of two public high schools in Pasadena.
 The other being Northeast High School, Chesapeake's rival school.
 Chesapeake opened in 1976 due to overcrowding at Northeast.
 It serves students in grades 9-12.
 The school serves the local feeder system, encompassing Chesapeake Bay Middle school and the respective six elementary schools that feed into it.
 The school has two floors and includes a football field, several soccer and other athletic fields, and a variety of gymnasiums, and including a smaller dance studio.
 Chesapeake's music department is extremely diverse.
 They have an A-Capella group named "Evolve", They have a group who sing classical and holiday pieces called "Chamber Singers", and lastly there is "Concert Choir".
 Chesapeake also offers musical talent through the expression of Musicals.
 The most recent musical were "In the Blink of an Eye"- Music Review, "Oklahoma" and "Grease"
South River High School is a large public high school in the United States, in the Annapolis suburb of Edgewater, Maryland in Anne Arundel County.
 It was built in 1978 and has 2,220 students currently enrolled, making it the largest public high school in Anne Arundel County (student body wise).
 It received a Blue Ribbon in education.
 Due to recent overcrowding in the Crofton area, students are bused in from Crofton, in addition to Davidsonville, Mayo, Riva, and Edgewater.
 South River's rival school is Arundel High School.
 South River has a great reputation throughout Maryland and is known as one of the best high schools in Anne Arundel County.
 In 2013, Newsweek ranked South River as one of the top 30 high schools in Maryland, and one of the top 1,000 in the country.
Lapeer East High School was a public high school located in Lapeer, Michigan.
 It was the rival school of Lapeer West High School.
 In 2010, all portable classrooms were removed and the school was reverted to 9-12 grade students.
 It was built in 1975 as a result of overcrowding of the former Lapeer High School, which became Lapeer West High School.
 Starting in 2014, Lapeer East will be renamed Lapeer High School due to the consolidation of the two high schools, the consolidation owing to declining enrollments at both high schools.
 Which was due to an increasingly low number of elementary and kindergarten enrollments.
Bishop Gorman High School (also commonly referred to as Gorman High School or BGHS) is a Roman Catholic, private, preparatory school located in Summerlin, Nevada.
 The school is administered by the Diocese of Las Vegas, and has been serving Clark County and the Las Vegas Valley for over 50 years.
 The school opened in 1954 and its mascot is a Gael, or mounted Irish Knight.
Durango High School is a public high school in Spring Valley, Nevada, USA, with an enrollment of approximately 2600 students.
 It is a part of the Area 4 region of the Clark County School District, which is the fifth largest school district in the United States.
 Durango High School's main sports rivals are Bishop Gorman High School and Spring Valley High School.
Holy Cross High School was an all-boys, Roman Catholic high school in River Grove, Illinois, USA that operated from August 1961 until June 2004.
 In December, 2003, the school announced that they no longer had enough funding or interest in enrollment to continue.
 Only 79 students took the entrance exam for the 2004-2005 school year, and at least 125 were necessary to keep the school open.
 In June, 2004, the neighboring all-girls high school Mother Theodore Guerin High School accepted all Holy Cross students, becoming coed and changing their name to Guerin College Preparatory High School.
 Students from Mother Guerin and Holy Cross had already been sharing each other's facilities for certain classes, such as drama, music, and foreign languages.
Norco High School is California Distinguished School public high school serving 2,206 students from grades 9-12 in Norco, California, United States.
 It is part of the Corona-Norco Unified School District.
 The current principal is Mr.Ibbetson.
 Their rival school is Centennial High School.
Durango High School, also known as the Durango 9-R Administration Building, is a former school in Durango, Colorado.
 It is listed on the National Register of Historic Places and the Colorado State Register of Historic Properties.
 The building opened in 1917, and served as a high school until 1976, after which it became the district administration building.
Robert L. Patton High School, commonly referred to as "Patton High School", is a public high school in Morganton, North Carolina.
 The school was built in 2007.
 The school mascot is a panther, and the rival school is Freedom High School.
 The schools are 5.9 miles apart.
Spring Valley High School is located in the Spring Valley community in unincorporated Clark County, Nevada, United States.
 The school, serving grades 9 through 12, is a past of the Clark County School District.
 The school's curriculum offers the advanced honors diploma.
 Their sports rivals are Durango High School, Sierra Vista High School, and Bonanza High School