What the average capacity stadium City London that belong school enrollment less than 30,000?
Institution Team City Province First season Head coach Enrollment Football stadium Capacity
Canadian Interuniversity Sport football
12896884
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Teams
Ontario University Athletics 
 Yates Cup
University of Windsor Lancers Windsor ON 1968 Joe D'Amore 13,496 South Campus Stadium 2,000
University of Western Ontario Mustangs London ON 1929 Greg Marshall 30,000 TD Waterhouse Stadium 10,000
University of Waterloo Warriors Waterloo ON 1957 Joe Paopao 27,978 Warrior Field 5,200
Wilfrid Laurier University Golden Hawks Waterloo ON 1961 Michael Faulds 12,394 University Stadium 6,000
University of Guelph Gryphons Guelph ON 1950 Stu Lang 19,408 Alumni Stadium 4,100
McMaster University Marauders Hamilton ON 1901 Stefan Ptaszek 25,688 Ron Joyce Stadium 6,000
University of Toronto Varsity Blues Toronto ON 1877 Greg Gary 73,185 Varsity Stadium 5,000
York University Lions Toronto ON 1969 Warren Craney 42,400 York Stadium 2,500
Queen's University Golden Gaels Kingston ON 1882 Pat Sheahan 20,566 Richardson Stadium 10,258
University of Ottawa Gee-Gees Ottawa ON 1894 Jamie Barresi 35,548 Gee-Gees Field 4,152
Carleton University Ravens Ottawa ON 1945 Steve Sumarah 25,890 Keith Harris Stadium 3,000
SELECT AVG Capacity FROM table WHERE City = london AND Enrollment < 30,000
london 30,000