First question: do you actually need one? Second question: how do we design it right?
The $30,000-$50,000 Question
A sump pump requirement is the single most expensive line item a drainage plan can trigger. Construction runs $30,000-$50,000 depending on discharge routing and backup power. On fire rebuilds, this requirement is usually introduced at plan check, after your budget is already set.
So the first thing we do is not design a pump. It is establish whether you actually need one.
How We Fight the Requirement
Plan checkers justify sump pumps with hydrology: post-development flow ponds where gravity cannot remove it. The counter is showing the opposite:
Calculate pre-fire and post-development flow rates
Show post-development Q does not exceed pre-fire Q
Use minor regrading to route water to an approved discharge point: street, approved drainage device, or existing pattern
LA County does not require hydrology reports, but they use them to justify pumps. When your analysis shows no net increase in flow, the pump requirement can often be removed. This is the analysis behind our hydrology reports, and it is why the $2,400 document is the best money on most projects.
When You Genuinely Need One
Some lots cannot drain by gravity no matter how the analysis shakes out: a side yard trapped between the house and a rising neighbor grade, a basement walkout below street level, a pad cut into the hillside. When the pump is real, it needs to be designed properly:
Sump location and capacity sized to the contributing area
Discharge routed to an approved point, not the neighbor's lot
Check valve and backflow provisions
Duplex pumps where the county requires redundancy
The design goes on your drainage plan sheets and gets reviewed with the building permit. When it is part of the plan, it does not add meaningful time to the 1-2 week turnaround.
Frequently Asked Questions
Plan checkers require a sump pump when your proposed grading leaves low points that cannot drain by gravity, typically where the lot slopes toward the house or a side yard is trapped. The requirement is justified by hydrology showing post-development flow ponding where it cannot get out.
A sump pump system adds $30,000-$50,000 to construction, depending on discharge routing and whether backup power is needed. This is why we fight the requirement before accepting it: many can be avoided with proper grading and flow analysis.
Often, yes. If hydrology shows your post-development flow does not exceed pre-fire flow, and minor regrading can route water to an approved discharge point, the pump requirement can be removed. LA County does not require hydrology reports, but they use them to justify pumps, so the analysis cuts both ways.
When a pump is genuinely needed, we design the sump location, capacity, discharge routing to an approved point, and check valve/backflow provisions. The design goes on your drainage plan sheets and gets reviewed with the building permit.
When it is part of a drainage plan, the pump design does not add meaningful time. It is included in the 1-2 week turnaround once we have your survey and site plan.
Get the Pump Question Answered Early
Before your architect finalizes grading, let us look at the lot. Removing a pump requirement costs a lot less than building one.