When I first saw this sign, with its ten kanji and one hiragana, I wondered what the first Haru no was modifying. The breakdown is this: the second and third kanji read chiiki and mean some kind of area or division or precinct; the fourth and fifth read anzen (safety); the sixth and seventh read und$#244;, which means "movement" or "campaign" in this case.

So Haru no ("spring") is modifying the second to seventh kanji, resulting in "The spring precinct safety campaign," which is being carried out by the Otsuka police station, as you can see from the horizontal writing at the bottom.

That leaves us with the final three kanji, the first two of which read jisshi, which is a noun and means "operation" or "enforcement" or something like that. The last kanji, chû, means that the preceding noun is in the "midst" of being carried out. So in this case it means that the spring precinct safety campaign is "in force," "in effect," "be enforced."

This is another case in which chû follows a noun (a noun indicating some kind of movement or action or process) and shows that that action is in the "midst" of being carried out. The chû combination can come at the end of a sentence, as here, or it can be used as a modifier in combination with no. E.g., jisshichû no anzen undû, meaning "the safety campaign that is now in effect." (kanji below)

(We) are fixing the sidewalk.

Hodô = walking road = sidewalk.
Naoshite imasu = naosu = fix = one of those common Japanese verbs that has innumerable meanings, 15 in my edition of the Kojien, all with the basic meaning of making something straight or right that is not straight or right.

The simplicity of the Japanese here is unusual. Nouns with multiple kanji are favored on most signs. Here it would normally have been simply kôjichû (under construction): to wit, see right:

Japanese Signs (4)

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