日治時期所興建的新式建築，建築的形式與風格象徵著地位與身分。該建築受日本明治維新後的建築影響，自來水博物館建築上多有和洋混合的建築細部或折衷形式，舉例如下：
- 圓頂、圓拱、古典柱式：受到古希臘與古羅馬的建築影響，而文藝復興之後，以及隨後的新古典主義建築，為影響本建築最大的建築形式；而圓頂在羅馬人的文化中用以象徵宇宙，亦常出現於羅馬帝國之後的拜占庭帝國建築。
- 拱窗：以半圓拱窗搭配拱圈。
- 屋頂：半圓銅板瓦造型屋頂，師法拜占庭與古典主義兩種風格。
- 柱式：愛歐尼克式柱式，羊角捲窩裝飾，為古希臘的三種柱式之一；柱頭形式來自於自然界貝殼或羊角。
- 窗戶：圓拱窗與方形窗是文藝復興以後的建築代表性特色。
- 拱門：飾以淺浮雕的拱門。
據考證當時留存的「臺北水道水源地唧筒室新建築圖」記載，推斷設計師應為「森山松之助」。
The new-style architecture adopted during the period when Taiwan was under Japanese rule often presented one's status and identity through a building's form and style. This building had influences from Japan's Meiji Restoration, in a hybrid of Japanese and European architectural elements, such as:
- Dome, Round Arches, and Classical Orders: Influenced not only by the architecture of classical Greece and Rome, but also that of the Renaissance and by Neoclassicism, the dome here was a symbol of the universe in Roman culture, and was an element also frequently used in the Byzantine Empire.
- Arched Windows: Semicircular arched windows with arched rings.
- Rooftop: Copper tiles cover the rooftop in imitation of Byzantine and Classical architecture.
- Orders: The Ionic orders, decorated with volutes, is one of three types of order popular during the ancient Greek period; the shape of the capitals imitates shells or goat horns.
- Windows: The circular arched windows and square windows are distinguishing features of post- Renaissance architecture.
- Arches: Decorated with low reliefs (also known as "bas-reliefs").
Based on the "New Architectural Drawing of Taipei Water Source Site Pumping Room" documentation left from the period, the architect is believed to be Mr. Matsunosuke Moriyama.
