Why is a high-voltage line that has run beneath Leetsdale Drive now being dug down East Cedar Avenue, South Birch Street and South Glencoe Street? Xcel Energy picked these streets on purpose, and its reasons explain everything South Hilltop has lived with since last winter.
The project is Xcel's Leetsdale-Monroe-Elati 230-kV Underground Transmission Line Replacement. It replaces a six-mile underground cable across central and southeast Denver with a larger, more modern system. Phase 1 is the 2.0-mile stretch from the Leetsdale substation to the Monroe substation, and it runs through the residential blocks of South Hilltop. Xcel says Phase 1 began in November 2025 and is scheduled to finish in spring 2027.
The busy roads are where the line can't go
The old line runs mostly beneath two of the city's busiest corridors. Xcel's spring 2026 project fact sheet puts the problem plainly:
"The existing underground transmission line must be relocated to be replaced due to its location predominantly beneath Leetsdale Drive and Speer Boulevard, both heavily used thoroughfares."
The fact sheet gives three reasons the new cable can't simply go back into the same trench. Crews would be working beside heavy traffic. The existing line has to stay energized while its replacement is built. And there isn't enough room underground to fit both. Xcel's November 2025 open house boards say the routing study avoided major collector and arterial roads. Once the new line is energized, the old one will be decommissioned and left in place.
What makes South Hilltop's streets a good route, then, is exactly what makes the work noticeable there. They are local streets with modest traffic, and they connect the substation on the Leetsdale side to Colorado Boulevard without running down a major corridor. Xcel also treated city-marked dedicated bike lanes as a routing constraint and worked to avoid them. The Hilltop Neighborhood Association's project page says the project "directly effects residents who live in South Hilltop."
The planned route, street by street
Xcel's November 2025 open house materials lay out Phase 1 as a chain of residential streets heading northwest from the Leetsdale substation:
- South Jersey Street
- East Virginia Avenue
- South Ivy Street
- East Dakota Avenue
- South Glencoe Street
- East Cedar Avenue
- South Birch Street
- East Ellsworth Avenue
The first four are south of Alameda Avenue. Hilltop's share starts where Glencoe crosses Alameda heading north. From there the line jogs west along Cedar, north on Birch, and onto Ellsworth, where it crosses Colorado Boulevard and keeps going west to the Monroe substation.
On paper, the work moves in order from the Leetsdale substation toward Monroe. On the ground it has been less tidy. The association's January 2026 newsletter announced that East Cedar would close between South Fairfax and South Eudora streets starting January 16, for up to three weeks. Xcel's current schedule lists the next block east, Cedar between Glencoe and Fairfax, for October 21 through November 11. South Birch between Cedar and Ellsworth and East Bayaud between Clermont and Bellaire were on the association's May 1 closure notice. Both showed up again on Xcel's October schedule.
Xcel's own Q&A explains why a street can see more than one round of work. If crews hit underground utilities that aren't on record, or find the existing records incomplete, work on that block can stop. Crews may then move to another location and come back once engineers have a fix. A closure on your block in spring doesn't mean your block is finished.
Where the trench sits as November begins
Xcel's schedule updated October 21 at 2 p.m. lists these Phase 1 closures in and next to South Hilltop. By November 5, some windows will have closed and others may have moved:
| Street | Segment | Scheduled window |
|---|---|---|
| East Bayaud Avenue | South Clermont to South Bellaire | October 15 to October 29 |
| South Birch Street | East Cedar to East Ellsworth | October 15 to October 29 |
| East Cedar Avenue | South Glencoe to South Fairfax | October 21 to November 11 |
| South Glencoe Street | East Cedar to East Alameda | October 21 to November 11 |
| East Ellsworth Avenue | South Colorado Boulevard to South Birch | October 26 to November 16 |
| East Ellsworth Avenue | South Colorado Boulevard to South Monroe | October 26 to November 16 |
| South Glencoe Street | East Alameda to East Dakota | October 28 to November 16 |
The two Ellsworth segments matter most. Ellsworth is the last street on Phase 1's planned route, and the segment west of Colorado Boulevard to Monroe is where the line leaves Hilltop. Xcel warns that any of these dates can slip because of weather, materials, crew availability or underground obstacles. It posts a new schedule weekly, and you can get the construction notices by email by writing to [email protected].
What a closed block means for the people who live on it
The trench takes up most of a residential street. Vault locations depend on where the existing water, sewer and gas lines happen to run, so Xcel can't promise the work will stay on one side. Each block closes in both directions. A typical closure lasts one to three weeks and can stretch to four. Shallow trench sections go faster than deep ones. Here is what Xcel has committed to for homes along the route:
- Advance notice. Door hangers go up three to five business days before work starts, and crews from the contractor, BT Construction, plan to knock on doors before starting a block.
- Work hours. Crews work Monday through Friday from 7 a.m. to 7 p.m. and Saturdays from 8 a.m. to 5 p.m. Evening, night or Sunday work is possible in certain situations.
- Garage access. At the end of each workday, crews pull the work zone in so residents can reach garages and homes outside working hours. During working hours the street may be blocked. Residents who work from home and need to leave midday can ask for accommodations ahead of time.
- Trash day. Xcel is coordinating with Denver Waste Collection. Crews may move carts to one side of the street for pickup and return them to your property afterward.
- Sidewalks. Sidewalks are meant to stay open. If any part of one is disturbed, Xcel's open house Q&A says it will restore it to its previous condition, ADA standards included.
- EV charging. If the trench blocks access to your usual charger, you may qualify for a pilot program that brings in a mobile charging unit. Per Xcel's project page, the company asks for seven days' notice when possible and requires a participation waiver.
- Property damage. Damage caused by the project goes through a claims process with BT Construction. You can start it by email, through the project phone line, or by talking to crews on site.
The project line is 303-716-8990.
After the trench comes the paving
Paving is the last disruption on each block, and for driveways it can be the tightest. During milling, Xcel expects to keep one lane open with flaggers directing traffic. Fresh asphalt needs time to cool, though, so paving brings temporary hard closures, and driveways are cut off until crews say they can be used again. Xcel asks residents to keep cars, bikes, feet and trash carts off new pavement until crews give the go-ahead.
West of Colorado Boulevard, Phase 2 is already underway. Xcel's schedule lists closures on East 4th Avenue between Fillmore and Clayton streets through November 6, and on Monroe Street between 1st and 3rd avenues through October 30. Phase 2 runs 4.0 miles from the Monroe substation to Elati and is scheduled to finish in spring 2028. Xcel expects the full line in service that year. For South Hilltop, the Ellsworth crossing at Colorado Boulevard is where the trench heads west out of the neighborhood. Whether nearby blocks see crews again before spring 2027 will show up in Xcel's weekly schedule, one block at a time.
At the Wolfe Bouc Team, we follow projects like this one block by block, because in Hilltop the details of a single street matter. If you have questions about how the Phase 1 work touches your own block, we'd welcome the conversation. Request a Private Consultation.
