California Code, Government Code - GOV § 65913.8

(a) The improvement is (1) designed and installed to serve only the specific development project on which the fee, charge, or other form of payment is imposed, (2) the improvement serves 19 or fewer lots or units, and (3) the local agency makes a finding, based upon substantial evidence, that it is infeasible or impractical to form a public entity for maintenance of the improvement or to annex the property served by the improvement to an entity as described in subdivision (b).

(b) The improvement is within a water district, sewer maintenance district, street lighting district, or drainage district.  In these circumstances, a payment for maintenance or operation may be required for a period not to exceed 24 months when, subsequent to the construction of the improvement, either the local agency forms a public entity or assessment district to finance the maintenance or operation, or the area containing the improvement is annexed to a public entity that will finance the maintenance or operation, whichever is earlier.  The local agency may extend a fee, charge, or other form of payment pursuant to this section once for whatever duration it deems reasonable beyond the 24-month period upon making a finding, based upon substantial evidence, that this time period is insufficient for creation of, or annexation to, a public entity or an assessment district that would finance the maintenance or operation.

As used in this section, “development project” and “local agency” have the same meaning as provided in subdivisions (a) and (c) of Section 66000.