San Diego Gas & Electric\u2019s Sunrise Powerlink transmission project is three-fourths complete but faces construction hurdles from birds and the San Onofre nuclear plant outage. According to an SDG&E April 16 filing with the California Public Utilities Commission, spring has sprung and so has bird romance. \u201cThe nesting season has begun and has the potential to delay overhead construction, should nesting occur near or in the work areas,\u201d according to SDG&E. Other construction problems include the ongoing outage of the 2,200 MW San Onofre nuclear plant. SDG&E must shut down part of its transmission system to complete work at the Encina and San Luis Rey substations. The continued outage of the nuke in the transmission-constrained region precludes SDG&E from temporarily flipping off part of its transmission. SDG&E owns 20 percent of the plant. Southern California Edison owns 78 percent and operates the facility. The project terrain has presented another challenge. \u201cThe inability to design access roads in certain areas due to environmental concerns has increased the need to access towers via helicopter,\u201d the filing notes. Since the project was permitted, the percent of towers installed via helicopter--far more costly than ground mounting--has risen from 20 percent to 70 percent. As of the end of March, SDG&E spent $1.64 billion on the 171-mile-long high voltage project stretching from Imperial County to San Diego.