We specialize in civil and drainage engineering services, including grading plans, drainage studies, hydrology and hydraulics (H&H) modeling, stormwater quality management plans (SWQMP), Water Quality Management Plans (WQMPs), erosion control plans, and HEC-RAS 1D/2D modeling for floodplain analysis.
We accept projects in California, Arizona, and North Carolina.
The cost of a grading plan will vary depending on the project size, site conditions, and jurisdiction requirements. Residential grading plans for single-family lots generally start around $2,300. Grading plans for hillside lots and complex sites will cost more. For a tailored estimate, we recommend reaching out with your site plan and project details.
A drainage study (also known as a hydrology report) evaluates existing and proposed flows on your site. Many jurisdictions require drainage studies (for some projects) before issuing building permits to ensure downstream properties and infrastructure are not adversely affected. Drainage studies may also include calculations that demonstrate that the onsite stormwater conveyance system is capable of conveying peak flows and that the site is meeting stormwater storage requirements.
Yes, we prepare erosion and sediment control plans. This is typically included in the cost of a grading plan for California projects.
No, we do not prepare Stormwater Pollution Prevention Plans (SWPPPs).
For a grading plan, we need your site plan, topographic survey, and project description. From there, we can prepare a scope of work and fee estimate. To begin work, we will need CAD files for the site plan and topographic survey. We will also need a copy of the soils report.
A grading plan + drainage study for a standard single-family residential project typically take 2–4 weeks to complete, depending on workload and the completeness of client-provided information. Larger or more complex projects may take longer.
We typically bill on an hourly basis at our standard professional rate, or on a lump-sum basis for clearly defined scopes of work. The billing method is outlined in your proposal and contract. The contract must be signed by Surf City H2o and the client before we begin work.
We accept mailed checks, Venmo, and Zelle.
For most projects, we require an upfront retainer or deposit (often 15% of the fee) before work begins. This ensures we can prioritize your project in our schedule.
If additional work is required outside the original scope, we will provide a written amendment with estimated fees for your approval prior to beginning work outside of the original scope of services.
Invoices are typically due within 30 days (Net 30) unless otherwise noted. Large or ongoing projects may be billed monthly as work progresses.
No. Agency review and permit fees are paid directly to the jurisdiction and are separate from our engineering services.
Yes. We provide written proposals outlining scope, estimated hours or lump-sum cost, and billing terms so there are no surprises.
Revisions are typical and a normal part of the review process for obtaining grading/building permits. Our proposals typically include responses to agency comments. If unexpected requirements arise outside the original scope, we’ll discuss them with you and prepare an amendment to the original contract if necessary.
To keep projects moving smoothly, we require staged (retainer and first submittal) or monthly payments. This arrangement ensures we can dedicate resources consistently to your project and avoid delays.
You will only be responsible for work completed up to the point in which the project was canceled. At that time, we will provide a detailed invoice so you can see exactly what work was performed. Any unused retainer funds will be sent back.
Quick clarifications are generally included, but extended calls, detailed reviews, or new analyses are considered billable time. We will always let you know if a request falls outside the agreed scope.