California Civil Code
When a person affixes his property to the land of another, without an agreement permitting him to remove it, the thing affixed, except as otherwise provided in this chapter, belongs to the owner of the land, unless he chooses to require the former to remove it or the former elects to exercise the right of removal provided for in Section 1013.5 of this chapter.
(a) When any person, acting in good faith and, erroneously believing because of a mistake either of law or fact that he has a right to do so, affixes improvements to the land of another, such person, or his successor in interest, shall have the right to remove such improvements upon payment, as their interests shall appear, to the owner of the land, and any other person having any interest therein who acquired such interest for value after the commencement of the work of improvement and in reliance thereon, of all their damages proximately resulting from the affixing and removal of such improvements.
(b) In any action brought to enforce such right the owner of the land and encumbrancers of record shall be named as defendants, a notice of pendency of action shall be recorded before trial, and the owner of the land shall recover his costs of suit and a reasonable attorney's fee to be fixed by the court.
(c) If it appears to the court that the total amount of damages cannot readily be ascertained prior to the removal of the improvements, or that it is otherwise in the interests of justice, the court may order an interlocutory judgment authorizing the removal of the improvements upon condition precedent that the plaintiff pay into court the estimated total damages, as found by the court or as stipulated.
(d) If the court finds that the holder of any lien upon the property acquired his lien in good faith and for value after the commencement of the work of improvement and in reliance thereon, or that as a result of the making or affixing of the improvements there is any lien against the property under Article XX, Section 15, of the Constitution of this State, judgment authorizing removal, final or interlocutory, shall not be given unless the holder of each such lien shall have consented to the removal of the improvements. Such consent shall be in writing and shall be filed with the court.
(e) The right created by this section is a right to remove improvements from land which may be exercised at the option of one who, acting in good faith and erroneously believing because of a mistake either of law or fact that he has a right to do so, affixes such improvements to the land of another. This section shall not be construed to affect or qualify the law as it existed prior to the 1953 amendment of this section with regard to the circumstances under which a court of equity will refuse to compel removal of an encroachment.
Where, from natural causes, land forms by imperceptible degrees upon the bank of a river or stream, navigable or not navigable, either by accumulation of material or by the recession of the stream, such land belongs to the owner of the bank, subject to any existing right of way over the bank.
If a river or stream, navigable or not navigable, carries away, by sudden violence a considerable and distinguishable part of a bank, and bears it to the opposite bank, or to another part of the same bank, the owner of the part carried away may reclaim it within a year after the owner of the land to which it has been united takes possession thereof.
Islands and accumulations of land, formed in the beds of streams which are navigable, belong to the State, if there is no title or prescription to the contrary.
An island, or an accumulation of land, formed in a stream which is not navigable, belongs to the owner of the shore on that side where the island or accumulation is formed; or, if not formed on one side only, to the owners of the shore on the two sides, divided by an imaginary line drawn through the middle of the river.
If a stream, navigable or not navigable, in forming itself a new arm, divides itself and surrounds land belonging to the owner of the shore, and thereby forms an island, the island belongs to such owner. (1019.) Section Ten Hundred and Nineteen. A tenant may remove from the demised premises, any time during the continuance of his term, anything affixed thereto for purposes of trade, manufacture, ornament, or domestic use, if the removal can be effected without injury to the premises, unless the thing has, by the manner in which it is affixed, become an integral part of the premises.