Storm drains collect and convey rainwater; they are different from sanitary sewer lines that carry wastewater from sinks, toilets and other fixtures. If you have standing water, a blocked inlet or a damaged private drain line, call to discuss the location and determine whether an independent drainage provider or public agency is the appropriate contact.
Storm drain or sanitary sewer?
A storm drain is intended to manage rainwater runoff, while a sanitary sewer carries wastewater from buildings. The systems have different functions and may have different owners and maintenance responsibilities. Identify which system is involved before authorizing work.
Common private-property drainage concerns
Blocked area drains, damaged underground yard drains, broken downspout connections and poor surface drainage can leave water standing near a building. A drainage professional may inspect inlets, grates, pipe routes and discharge points.
When a public agency may be responsible
If the issue appears to involve a public street inlet, public right-of-way or municipal stormwater infrastructure, contact the appropriate city or county department before arranging private excavation. Responsibility depends on the exact location and asset.
What an assessment should include
Ask the provider to identify the water source, inspect the accessible route, explain the proposed repair, confirm where runoff will discharge and clarify any permits or agency coordination required.
How to prepare for a provider visit
- Note which fixtures are affected and whether the problem is recurring.
- Identify any accessible sewer cleanout and the approximate route of the pipe.
- Share prior camera reports, cleaning records or repair invoices if available.
- Ask for a written scope, itemized price and any permit or restoration exclusions.
Related sewer service guides
Sewer Line Repair · Sewer Line Cleaning · Sewer Camera Inspection
Frequently asked questions
Are storm drains the same as sewer lines?
No. Storm drains convey rainwater runoff; sanitary sewer lines convey wastewater from buildings.
Can a plumbing company repair a storm drain?
Some drainage contractors offer private-property storm drain services. Confirm the specific capability and responsibility for the affected asset before scheduling.
Should I call the city about a street drain?
For an inlet or drain located in a public street or right-of-way, contact the city or relevant public agency to determine responsibility.
For general local information, return to the main SewerCare Pro sewer line repair guide for Diamond Bar. SewerCare Pro connects callers with independent providers; it does not employ the contractors who inspect or repair the pipe.